<p><strong>This study presents a one-year assessment of microplastic concentrations in the River Rhine, analyzing samples from three locations and across multiple size fractions using TED-GC/MS. Dominant polymers included polyethylene, polypropylene, polystyrene, styrene–butadiene rubber, and natural rubber.</strong></p><p>Statistical analysis revealed size-dependent distributions, minor seasonal variation, and spatial differences, highlighting the role of sources such as tire abrasion. The findings provide valuable data for environmental monitoring, ecotoxicological research, and regulatory frameworks related to water quality.</p><blockquote><h4><strong>The original article</strong></h4><h4><a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsestwater.5c00530"><strong>One Year Observation of Microplastic Concentrations in the River Rhine</strong></a></h4><p>Yosri Wiesner, Paul Eisentraut, and Korinna Altmann*</p><p>ACS EST Water 2026, 6, 2, 639–648</p><p><a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.1021/acsestwater.5c00530">https://doi.org/10.1021/acsestwater.5c00530</a></p><h6>licensed under <a target="_blank" rel="noopener noreferrer" href="https://creativecommons.org/licenses/by/4.0/"><strong>CC-BY 4.0</strong></a></h6></blockquote><p><strong>Selected sections from the article follow. Formats and hyperlinks were adapted from the original.</strong></p><div><p>As microplastics (MPs) are found all over the world and no comprehensive knowledge is available yet, extensive monitoring campaigns are required to gain a full understanding of their occurrence, transportation and fate. <a href="javascript:void(0);">(1,2)</a> In particular, MP abundance in freshwater systems has still not been sufficiently investigated. <a href="javascript:void(0);">(3,4)</a> Additionally, the question of the toxicological potential of MPs has been the subject of numerous studies for many years, <a href="javascript:void(0);">(5,6)</a> leading to more precise and complex experimental set-ups and results. However, there is still a need for more acurate data on environmental MP concentrations in order to make ecotoxicological tests even more detailed and realistic. The lack of certainty for exposure concentrations in the risk assessment frame of MPs leads to the precautionary principle being applied by politicians and regulators worldwide. Both the EU drinking water directive and the wastewater directive call for monitoring of MPs within the next few years. It is important to establish suitable analytical methods for sampling, sample preparation and detection that must now be fast, robust and fit for purpose in order to obtain representative and valid results depending on mass or particle number. <a href="javascript:void(0);">(7−9)</a></p><p>MPs are solid particles with a size of 1–1000 μm mainly consisting of polymers (ISO/TR 21960, 2020) and can, for example, result from industrial production in the form of small particles that are designed as additives and change the properties of products, or from plastic parts that have been released into the environment. Major sources of MPs today are paints, tires, packaging materials, pellet waste and textiles. <a href="javascript:void(0);">(10−12)</a> These macroplastic products can form MP particles as a result of degradation factors such as photooxidation, hydrolysis and mechanical abrasion. <a href="javascript:void(0);">(13,14)</a></p><p>The River Rhine has its origin in Switzerland and then flows through Liechtenstein, Austria, Germany and France until it discharges into the North Sea in The Netherlands. At 1233 km and a catchment area of about 185&nbsp;000 km<sup>2</sup>, the Rhine is one of the largest river systems in Europe and, due to its expanse, forms the ecological basis for a large number of animal species. Around 30 million people in Germany are supplied with drinking water from the Rhine.</p><p>It is hardly possible to assess the occurrence of MPs if either a limited sampling volume is used or only individual samples are taken. It is therefore essential that different volumes are sampled depending on whether the water to be sampled contains many or few MP particles. It is recommended to sample at least 5 m<sup>3</sup> for drinking water samples and 1 m<sup>3</sup> for surface water, whereas raw wastewater contains so many particles that only a few liters need to be sampled. <a href="javascript:void(0);">(15)</a> Although sampling of these water volumes leads to a representative sample from the analytic point of view, it is questionable, if the result measured is representative for the location. Previous studies have shown that the composition in terms of MP masses in a water body can change at one location with each individual sample independently whether several samples are analyzed in 1 day or spread over several days. <a href="javascript:void(0);">(16)</a> Fractionated filtration and sedimentation boxes as active and passive sampling methods have proven themselves in the sampling of freshwater systems. In active sampling, water is fractionally filtered using a pump and a sieve tower with different mesh sizes. <a href="javascript:void(0);">(17)</a> Passive sampling can be carried out using sedimentation boxes. <a href="javascript:void(0);">(18)</a> In a sedimentation box, the flow velocity of the medium flowing through is reduced by using several baffle plates. Due to the reduced velocity and energy, particles up to a certain size are forced to sediment by the now predominant gravitational force. Such boxes can remain in the water for several weeks and therefore collect a cross-section of the suspended particles including MP over a certain period of time.</p><p>Mass and number-based methods have emerged as suitable detection methods for MPs. <a href="javascript:void(0);">(19)</a> Number-based methods such as μ-Raman, μ-FTIR or LDIR are well advanced to evaluate the polymer identity, particle number concentration and shape, <a href="javascript:void(0);">(20,21)</a> but are still time-consuming in terms of sample preparation. In regulatory approaches or for simulations, usually the MP mass is needed. MP polymer identity and masses can be detected by thermoanalytical methods like pyrolysis-GC/MS (Py-GC/MS) or thermal extraction desorption-GC/MS (TED-GC/MS). Especially TED-GC/MS seems to be suitable for monitoring purses of suspended particulate matter, because there is no need for additional sample preparation others than filtration and homogenization. Up to 50 mg of suspended particulate matter can be directly measured in one run, giving representative subsamples for precise measurements exceeding the limit of quantification. Furthermore, styrene–butadiene rubber (SBR) and natural rubber (NR) as indication for tire wear can be detected in the same sample run next to thermoplastics such as polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polystyrene (PS), polyamide 6 or polyacrylates.</p><p>This work provides a comprehensive data set of MP concentrations of the River Rhine over one year sampling at three different locations starting near the source in Weil via Koblenz and Emmerich. Sampling was done with sedimentation boxes with monthly withdrawal and fractioned filtration of the collected particles afterward. The size fractions 10–50 μm, 50–100 μm and 100–500 μm were provided by the Federal Institute of Hydrology (BfG, Germany) and analyzed at the Federal Institute of Material Research and Testing (BAM, Germany) funded by a national project from the Federal Ministry for the Environment, Nature Conservation, Nuclear Safety and Consumer Protection (BMUV, Germany, 3719 22301 0). Detection was performed with TED-GC/MS in routine mode, proven as a fast and robust detection method. <a href="javascript:void(0);">(2,16,22)</a> Data can be used, for example, for water monitoring or as reference values for future risk assessment scenarios and experiments.</p><h4><strong>2. Materials and Methods</strong></h4><h5><strong>2.2. TED-GC/MS</strong></h5><p>TED-GC/MS is a multistage detection technique combining the thermal sample extraction by thermogravimetric analysis (TGA) with chromatographic separation of the individual decomposition gases and detection by trace analysis with gas chromatography/mass spectrometry (GC/MS). Sample material in 150 μL alumina crucibles was pyrolyzed in a <strong>TGA2 thermobalance</strong> (MettlerToledo, Gieβen, Germany) under a nitrogen flow of 30 mL/min from 200 to 500 °C with a heating rate of 10 K/min. Typical sample intake was between 10 to 50 mg depending on the organic content. The decomposition gases were collected on a solid phase (SorbStar, Envea, Vohenstrauβ, Germany) in the typical polymer decomposition temperature range between 200 and 500 °C via a heated coupling module (240 °C, Gerstel, Mülheim an der Ruhr, Germany). The loaded solid phase was transported to the thermodesorption unit (TDU)-GC/MS by an autosampler (<a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=8&amp;search=MultiPurposeSampler+2"><strong>MultiPurposeSampler 2</strong></a> (MPS2), Gerstel, Mühlheim an der Ruhr). The desorption of the decomposition products took place in the TDU (50–200 °C, 5 min isothermal, He gas, Gerstel), the cryofocusing in the cold injection system (−100 °C, Gerstel). Injection was carried out from there by rapid heating (−100–270 °C, 12 K/s) onto the separation column (HP5 ms, 1 mL/min He, 40–300 °C, Agilent, Palo Alto, USA) in the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=7890B"><strong>GC system (7890 B Agilent)</strong></a>. After chromatographic separation, detection was performed in a mass spectrometer (EI, 70 eV, scan-mode, <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=5977B"><strong>5977 B, Agilen</strong></a>t).</p><h4><strong>3. Results and Discussion</strong></h4><p>A summary of the identified polymer types and their corresponding mass concentrations per sampling location is provided in <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsestwater.5c00530#fig1">Figure 1</a>. All individual results are presented in <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/suppl/10.1021/acsestwater.5c00530/suppl_file/ew5c00530_si_001.pdf">Table S1</a> of the Supporting Information. With a few exceptions, the polymers PE, PP, PS, SBR and NR were detected. To cope with the large amount of measurement data and to obtain an overview of possible correlations, the data was evaluated using statistical and mathematical algorithms. Only the five polymers named above provide enough input data and are therefore used as the basis for the data analysis. The individual results were sorted according to various aspects that are included in the data set as independent variables:</p><p>(I)&nbsp;&nbsp;&nbsp; Particle size fractions</p><p>(II)&nbsp;&nbsp;&nbsp; Temporal variation</p><p>(III)&nbsp;&nbsp;&nbsp; Spatial variation due to the sampling locations</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ACS_EST_Water_2026_6_2_639_648_Figure_1_Overview_of_sampling_locations_along_the_German_part_of_the_River_Rhine_and_sum_of_identified_median_mass_concentrations_fe570f51b5.jpg" alt="ACS EST Water 2026, 6, 2, 639–648: Figure 1. Overview of sampling locations along the German part of the River Rhine and sum of identified median mass concentrations." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ACS_EST_Water_2026_6_2_639_648_Figure_1_Overview_of_sampling_locations_along_the_German_part_of_the_River_Rhine_and_sum_of_identified_median_mass_concentrations_fe570f51b5.jpg 158w," sizes="100vw" width="1883" height="1860"></p><p>The concentrations of the various polymers in the suspended matter serve as input values. The riverine balancing and material transport based on the total masses (polymer mass in total suspended solids mass) is carried out explicitly and will be published at Umweltbundesamt as part of the project report by the BfG (Ternes, final project report, 2023).</p><h5><strong>3.1. Particle Size Fractions</strong></h5><p>This section describes the possible correlation of the polymer mass concentration with the size of the measured particles regardless of the sampling location. Therefore, the generated samples were sorted by sieving into different size fractions of 10–50, 50–100 and 100–500 μm. The relative mean values of the individual fractions are calculated (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/suppl/10.1021/acsestwater.5c00530/suppl_file/ew5c00530_si_001.pdf">Figure S2</a>) to obtain the shares of the different polymer types in the total amount of MP. PE is the dominant polymer in all size fractions with 68–76%, followed by PS (10–15%), SBR (4–13%), PP (2–5%) and NR (2–4%). Obviously, all polymer types are approximately evenly distributed across the size fractions, with SBR being less present in the 100–500 μm fraction.</p><p>In general, it can be determined that PE accounts for the highest proportion of MP. PS makes up the second highest proportion, followed by SBR. Next in line are PP and NR. The polymer findings are in good agreement with previous MP studies of the Rhine. PE, PP and PS in particular are the most frequently detected polymers. <a href="javascript:void(0);">(3)</a> The relative abundance of PE, PP and PS is also relatively similar to Skalska et al., even when the particle number was considered here. <a href="javascript:void(0);">(26)</a> Especially in comparison with the results of Mani et al. significant similarities to the ratios of PE, PP and PS can be found. Data on SBR from tire abrasion in the Rhine is difficult to find in existing studies, as such particles cannot easily be identified using vibrational methods due to the IR absorbing properties and the intense fluorescence of the accompanying soot. However, a comparison with suspended particulate matter samples from the Danube is possible, as here the detection was also carried out using TED-GC/MS. <a href="javascript:void(0);">(2)</a> The relative ratios of PE, PP, PS, SBR and NR are comparable and support the plausibility of the results.</p><p>Total MP mass concentrations are presented in <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/suppl/10.1021/acsestwater.5c00530/suppl_file/ew5c00530_si_001.pdf">Figure S3</a> for individual polymer types, showing highest mass concentrations in the size fraction 100–500 μm. The median varies from 0.17 to 6.80 μg/mg depending on the polymer type. In absolute terms, the PE mass concentrations are significantly higher than those of all other polymers. PP and PS show a strong mass increase in the 100–500 μm fraction, together with higher uncertainty compared to 10–50 μm and 50–100 μm. With a variation of 0.27–0.32 μg/mg across all particle size fractions, the mass contents of SBR are relatively constant, while NR mass concentration seems to increase more linearly. The high mass concentrations and the strong scattering of the 100–500 μm fractions could be due to the presence or absence of large but few particles. Basically, the larger a particle is, the higher its contribution to the mass concentration. In contrast, the larger a particle is, the lower the probability of an equal distribution in all samples.</p><p>If other regions associated with the Rhine are considered, comparable ratios of mass concentration in the various particle size fractions are found in Rhine floodplains. <a href="javascript:void(0);">(27)</a></p><p>At the beginning of the data analysis, a Principal Component Analysis (PCA) is carried out to identify parameters that have a high influence on the mass content. This analysis identified that the particle size has the greatest influence on the mass concentration (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsestwater.5c00530#fig2">Figure 2</a>). The first principal component (PC 1) was identified as the particle size fraction and explains over 50% of the differences in the data.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ACS_EST_Water_2026_6_2_639_648_Figure_2_PCA_Score_plot_of_mass_concentrations_of_the_different_polymers_be94ae16c4.jpg" alt="ACS EST Water 2026, 6, 2, 639–648: Figure 2. PCA Score plot of mass concentrations of the different polymers." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ACS_EST_Water_2026_6_2_639_648_Figure_2_PCA_Score_plot_of_mass_concentrations_of_the_different_polymers_be94ae16c4.jpg 184w," sizes="100vw" width="747" height="635"></p><h4><strong>4. Conclusion</strong></h4><p>This study demonstrated that long-term sampling of the Rhine is possible and provides plausible results, which is important for future MP monitoring campaigns, as required by the Urban Waste Water Treatment Directive for the EU. Although the MP concentrations in the Rhine are relatively constant, seasonal and downstream differences were observed. In order to confirm these possible trends, further sampling campaigns are needed to identify possible differences on an annual scale. Furthermore, the influences of urban proximity and land use must be examined in greater detail by increasing the number of measuring points. Additional sample sites are needed to identify possible sources of input. This would be particularly important to clarify the PS concentrations, which show a high correlation between the different particle size fractions in almost all seasons and could indicate a possible common source. SBR is the only polymer to show a relatively constant concentration across all particle sizes and seasons, independent of the river course. Since it is a tire component, constant road traffic could be part of the explanation. However, a different particle ratio must be assumed here compared to the other polymers. The fragmentation mechanism and/or another transport mechanism needs to be clarified.</p><p>Although PE constitutes the majority of the total MP concentration, there may be an overestimation due to false positive signals. To exclude or confirm this, further studies must be conducted to analyze the organic components of the riverine suspended matter in detail.</p><p>A comparison with other studies reveals similar occurrences of the same polymer types and in parts also similar seasonal fluctuations and a slight downstream increase. The differentiated presentation of results in polymer type, particle size fraction and range of mass concentrations can provide a valuable basis for more complex and realistic exposure tests for ecotoxicological studies on freshwater organisms. In particular, the large database for SBR as a tire component could be of special interest, as the toxicity of tire particles due to their chemical composition has already been shown in other studies. In studies using FTIR-based detection methods, these values are usually missing due to the high absorbance of the black tire particles.</p></div>

One Year Observation of Microplastic Concentrations in the River Rhine

<p><strong>This study presents a novel MS/MS filtering tree approach for distinguishing regio- and stereoisomeric bile acids in untargeted LC-MS/MS data. By leveraging intensity ratios of closely related fragment ions, the method overcomes limitations of traditional spectral matching, enabling more accurate isomer annotation.</strong></p><p>A user-friendly web-based application was developed to facilitate implementation without coding expertise. Applied to public datasets, the workflow revealed diet-associated bile acid patterns across mammalian species and enabled identification of previously uncharacterized compounds, demonstrating its potential for large-scale metabolomics studies.</p><blockquote><h4><strong>The original article</strong></h4><h4><a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.analchem.5c05677"><strong>MS/MS Mass Spectrometry Filtering Tree for Bile Acid Regio- and Stereoisomer Annotation</strong></a></h4><p>Ipsita Mohanty, Shipei Xing, Vanessa Castillo, Julius Agongo, Abubaker Patan, Yasin El Abiead, Helena Mannochio-Russo, Wilhan D. Gonçalves Nunes, Jasmine Zemlin, Itzhak Mizrahi, Dionicio Siegel, Mingxun Wang, Lee R. Hagey, and Pieter C. Dorrestein*</p><p>Anal. Chem. 2026, 98, 6, 4571–4584</p><p><a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.1021/acs.analchem.5c05677">https://doi.org/10.1021/acs.analchem.5c05677</a></p><h6>licensed under <a target="_blank" rel="noopener noreferrer" href="https://creativecommons.org/licenses/by/4.0/"><strong>CC-BY 4.0</strong></a></h6></blockquote><p><strong>Selected sections from the article follow. Formats and hyperlinks were adapted from the original.</strong></p><div><p>Cholesterol-derived steroid molecules, known as bile acids, have been detected in nearly every organ where they have been studied. <a href="javascript:void(0);">(1)</a> Alterations in bile acid composition and dysbiosis have been linked to various health conditions, including neurocognitive developmental disorders, cancer, infections, and metabolic diseases such as diabetes and inflammatory bowel disease (IBD). <a href="javascript:void(0);">(2−8)</a> In the last 5 years, the number of detected bile acids in metabolomics experiments <a href="javascript:void(0);">(1,9−15)</a> has increased by the 1000s and possibly approaching 10,000s - most of which have not yet been fully structurally characterized. <a href="javascript:void(0);">(1,6,16−19)</a> We believe this is only the tip of the iceberg and that in the next 5 years this number will continue to increase. The scale of the bile acid pool and the challenge of accurately detecting and describing their structure truly represent an exciting frontier for analytical and computational scientists who continue to push the boundaries of what is possible.</p><p>In humans, bile acids are predominantly derived from cholesterol through pathways that exist not only in the liver as previously thought but also in many other organs including kidneys and brain. <a href="javascript:void(0);">(16,20,21)</a> These pathways shorten the side chain, producing a carboxyl terminus on the remaining 24-carbon steroid structure, which consists of four interconnected rings and side chain, collectively referred to here as the “core” (colored in <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.analchem.5c05677#fig1">Figure 1</a>a). The core of bile acids undergoes multiple hydroxylations, a process typically associated with the liver but also occurring in other organs such as the brain, kidney, and spleen. <a href="javascript:void(0);">(16)</a> Considering hydroxylation at known carbon positions on bile acids reported from human samples (as starred in <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.analchem.5c05677#fig1">Figure 1</a>a, <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/suppl/10.1021/acs.analchem.5c05677/suppl_file/ac5c05677_si_002.xlsx">Supplementary Table S1</a>) along with stereoisomers and allo versus nonallo A/B ring isomerization at C5, approximately 1,800 candidate mono-, di-, and trihydroxy C<sub>24</sub> bile acid cores are theoretically possible (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.analchem.5c05677#fig1">Figure 1</a>a). This number further expands exponentially in the gut.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Anal_Chem_2026_98_6_4571_4584_Figure_1_MS_MS_fragmentation_of_bile_acid_isomers_9bfcc8779d.jpg" alt="Anal. Chem. 2026, 98, 6, 4571–4584: Figure 1. MS/MS fragmentation of bile acid isomers. (a) Structure of bile acids highlighting mono-, di-, and trihydroxylated steroid cores, with experimentally observed potential hydroxylation sites on the steroid core indicated by red stars. (b) MS/MS fragmentation spectra of the regioisomers, taurochenodeoxycholic (TCDCA) acid and taurodeoxycholic acid (TDCA), illustrating a low-intensity mass region containing ions unique to each isomer. (c) Enlarged view of the MS/MS fragmentation spectra for taurochenodeoxycholic and taurodeoxycholic acids, emphasizing the ion pair used to calculate relative intensity ratios for differentiating these isomers." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Anal_Chem_2026_98_6_4571_4584_Figure_1_MS_MS_fragmentation_of_bile_acid_isomers_9bfcc8779d.jpg 245w," sizes="100vw" width="2100" height="890"></p><p>Recently, we developed MS/MS fragmentation-based filters using a Mass Spectrometry Query Language (MassQL), a query language that allows filtering of data patterns <a href="javascript:void(0);">(49)</a> to retrieve all MS/MS spectra from the Orbitrap data sets in GNPS/MassIVE repository containing bile acid-specific fragment ions. After merging similar spectra, this resulted in a reference library of 21,549 MS/MS spectra. <a href="javascript:void(0);">(1)</a> This library includes MS/MS spectra of known and many yet-to-be structurally characterized bile acid candidates that have already been detected from public metabolomics data repositories. This also includes MS/MS of multiple ion forms such as different adducts, in-source fragments, and multimers, <a href="javascript:void(0);">(1)</a> which all help in the annotation of bile acids. This MassQL library enables the annotation of the number of hydroxyl groups on the bile acid core, as well as the identification of potential modifications, and ∼ 62% of the atomic compositions are annotated. Other spectral “modifications” that do not have a distinct atomic composition may be different adducts or multiple combinations of adducts, in source fragments, and multimers. However, the diagnostic bile acid MS/MS fragments used to build this reference library do not allow for the differentiation between regio- and stereoisomers. Also, MS/MS spectral matching with the candidate library using the cosine metric often overlooks finer details within fragment ions, as minor peak intensity changes or low-intensity fragment ions have a minimal influence on overall spectral match scores (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.analchem.5c05677#fig1">Figure 1</a>b).</p><p>Based on our manual inspection of hundreds of bile acid MS/MS spectra, we observed and hypothesized that information in the low-intensity MS/MS fragments, including specific ion pairs, their intensity ratios, and unique ions, could be used to distinguish the steroid core isomers. As proof of concept in leveraging MS/MS data to enable further refinement of the stereo and regiochemistry of the hydroxylations of the bile acids cores, we developed a MassQL-based filtering tree utilizing key marker ions and their intensity ratios within narrow <i>m</i>/<i>z</i> windows to propose regio- and stereoisomer assignments of bile acids solely from MS/MS data. In this study, we focus on bile acid amidates, a class of structures found in humans and other animals.</p><h4><strong>Experimental Section</strong></h4><h5><strong>MS/MS Data Acquisition of Taurine-Conjugated Bile Acids</strong></h5><p>We generated one mM stock solutions of our in-house collection of 48 taurine-conjugated bile acids in 100% MeOH. The standards used in this study were obtained from the bile acid collection of the late Dr. Alan Hofmann’s laboratory at UCSD. The Dorrestein laboratory inherited these standards after his demise. The standard samples were injected (5 μL) into a Vanquish ultrahigh-performance liquid chromatography (UHPLC) system coupled to a <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/559"><strong>Q-Exactive quadrupole Orbitrap mass spectrometer</strong></a> (Thermo Fisher Scientific, Waltham, MA). A <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/1509"><strong>Kinetex polar C18 column</strong></a> (2.1 × 100 mm, 2.6 μm particle size, 100 A pore size; Phenomenex, Torrance) was employed with a SecurityGuard C18 column (2.1 mm ID) at 40 °C column temperature. The mobile phases (0.5 mL/min) were 0.1% formic acid in both water (A) and ACN (B) with the following gradient: 0–0.5 min 5%B, 0.5–1.1 min 5–25%B, 1.1–7.5 min 25–40%B, 7.5–8.5 min 40–99%B, 8.5–10 min 99%B, 10–12 min 5%B. The mass spectrometer was operated in positive heated electrospray ionization with the following parameters: sheath gas flow, 53 AU; auxiliary gas flow, 14 AU; sweep gas flow, 3 AU; auxiliary gas temperature, 400 °C; spray voltage, 3.5 kV; inlet capillary temperature, 269 °C; S-lens level, 50 V. MS1 scan was performed at <i>m</i>/<i>z</i> 150–1500 with the following parameters: resolution, 35,000 at <i>m</i>/<i>z</i> 200; maximum ion injection time, 100 ms; automatic gain control (AGC) target, 1E6. Up to 5 MS/MS spectra per MS1 scan were recorded under the data-dependent mode (dd-MS<sup>2</sup>) with the following parameters: resolution, 17,500 at <i>m</i>/<i>z</i> 200; maximum ion injection time, 150 ms; AGC target, 5.0E5; MS/MS precursor isolation window, <i>m</i>/<i>z</i> 1; isolation offset, <i>m</i>/<i>z</i> 0.5; normalized collision energy (NCE) of 45%; minimum AGC for MS/MS spectrum, 2.5E4; apex trigger, 2 to 5 s; dynamic precursor exclusion, 8 s. Fragmentation was performed in the HCD cell using nitrogen as the collision gas. The data was deposited in GNPS/MassIVE and is publicly available at MSV000092003. The MS/MS spectra are also added now to the GNPS spectral library - BILELIB19 (<a target="_blank" rel="noopener noreferrer" href="https://gnps.ucsd.edu/ProteoSAFe/gnpslibrary.jsp?library=BILELIB19">https://gnps.ucsd.edu/ProteoSAFe/gnpslibrary.jsp?library=BILELIB19</a>)</p><h4><strong>Results and Discussion</strong></h4><h5><strong>Retrospective Bile Acid Isomer Profiling in a Public Data Set of Animals with Different Diets</strong></h5><p>To illustrate the utility of the MassQL multistep filtering trees in retrospectively analyzing data in public repositories, we selected a publicly available data set containing feces from 40 animals (13 mammalian species) from the Zoological Center Tel Aviv-Ramat Gan, Israel. <a href="javascript:void(0);">(62)</a> The data set consisted of 3 herbivores, 23 omnivores, and 13 carnivores (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.analchem.5c05677#fig4">Figure 4</a>a). We selected this data set as we had previously confirmed detection of 6 previously uncharacterized polyamine-conjugated bile acids that we could not confirm with retention times as none of the standards we had synthesized matched, although their MS/MS did. We showed that their levels were higher in carnivores compared to herbivores and omnivores; <a href="javascript:void(0);">(1)</a> however, we were still unable to resolve the regio- and stereochemistry of all possible isomers of polyamine-conjugated bile acids. To further dive into the diversity of bile acids, we matched the MS/MS spectra of this study against the GNPS spectral libraries, including the candidate bile acid MS/MS reference library that we had previously created from the repository scale analysis. <a href="javascript:void(0);">(1)</a> This revealed 993 MS/MS spectral matches to bile acids. We next applied the multistep MassQL queries to resolve the regio- and stereochemistry of the bile acids. The steps described in this section follow the same filtering approach as outlined for the dihydroxy bile acid filtering tree (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.analchem.5c05677#fig2">Figure 2</a>).&nbsp;</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Anal_Chem_2026_98_6_4571_4584_Figure_2_Development_of_MSMS_fragmentation_based_Mass_QL_filtering_tree_2227b688a9.jpg" alt="Anal. Chem. 2026, 98, 6, 4571–4584: Figure 2. Development of MS/MS fragmentation-based MassQL filtering tree. Sequential MS/MS fragmentation-based filtering tree designed to classify regio- and stereoisomers of dihydroxylated bile acids. Structures at each filtering step are shown, with terminal bins color-coded for clarity." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Anal_Chem_2026_98_6_4571_4584_Figure_2_Development_of_MSMS_fragmentation_based_Mass_QL_filtering_tree_2227b688a9.jpg 183w," sizes="100vw" width="1000" height="852"></p><p>Step 1 excludes MS/MS spectral matches to candidate bile acids where the experimental spectra lacked the two diagnostic MS/MS ions for bile acids. Steroids and lipids often exhibit similar MS/MS spectra to bile acids, sometimes yielding high cosine similarity scores (&gt;0.7), yet they lack key low-intensity diagnostic ions. Due to the low intensity of these ions, their presence or absence typically does not significantly affect spectral matching scores. However, our MassQL isomer filters in Step 1 identified these MS/MS spectra to reveal that 543 MS/MS spectra had the two characteristic fragment ions for mono-, di-, and trihydroxy bile acids (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.analchem.5c05677#fig4">Figure 4</a>a). A portion of the 543 MS/MS spectra are adducts, in-source fragments, and multimers, overall reducing the number of unique bile acid structures. Based on retention time and peak shape correlation analysis in MZmine4, <a href="javascript:void(0);">(63)</a> a strategy that allows the discovery of ion forms associated with a specific molecule, we estimate these to represent 402 bile acids. Even though the data contained evidence for hundreds of unique bile acids, the stereo- and regiochemistry of hydroxylations were yet to be defined.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Anal_Chem_2026_98_6_4571_4584_Figure_4_Filtering_of_bile_acid_isomers_in_an_untargeted_LC_MS_MS_data_set_d7f119b028.jpg" alt="Anal. Chem. 2026, 98, 6, 4571–4584: Figure 4. Filtering of bile acid isomers in an untargeted LC-MS/MS data set. Representative example for using the MassQL filters for identifying bile acid isomers. (a) Overview of study design. Fecal samples from herbivores (n = 3), omnivores (n = 23), and carnivores (n = 13) were analyzed by LC-MS/MS and processed using MZmine4 and FBMN on GNPS2. Stepwise MassQL filtering refined candidate bile acids from 543 features (Step 1) to 96 (Steps 2 and 3) and 49 stereo and regiochemistry assigned MS/MS spectra (Step 4). Differential abundance of bile acids between herbivores/omnivores and carnivores is illustrated in the volcano plots (b) at Step 1 and (c) Step 4 of the dihydroxy filtering tree. The annotation of a previously uncharacterized bile acid was refined from (OH)2-N-acetyl-putrescine to 3,12α-N-acetyl-putrescine." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Anal_Chem_2026_98_6_4571_4584_Figure_4_Filtering_of_bile_acid_isomers_in_an_untargeted_LC_MS_MS_data_set_d7f119b028.jpg 243w," sizes="100vw" width="1819" height="1170"></p><p>The application of our MassQL filtering tree allowed us to further refine structural details within the bile acid core. After Step 2 and Step 3 of the MassQL filtering, we separated the amidated mono-, di-, and trihydroxylated bile acids from their ketones and unconjugated versions to give 96 bile acids (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.analchem.5c05677#fig4">Figure 4</a>a). A univariate analysis at Step 1 of bile acid annotations showed a higher abundance of almost all bile acids in the carnivores compared to herbivores and omnivores combined (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.analchem.5c05677#fig4">Figure 4</a>b). As we move down the MassQL filtering tree to Step 4, we can now hypothesize the regio- and, in many cases, the stereochemistry of their hydroxyl positions. With the current implementation of the tree, we can predict the bile acid cores of 49 MS/MS spectra (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.analchem.5c05677#fig4">Figure 4</a>a). The highest number of spectral matches that could be assigned are dihydroxylated bile acids, symbolized here as (OH)<sub>2</sub> (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.analchem.5c05677#fig4">Figure 4</a>c). These were categorized into individual bins of 3,12α-(OH)<sub>2</sub>, 3,7-(OH)<sub>2</sub>; 3,6-(OH)<sub>2</sub>; 3,12β-(OH)<sub>2</sub>; 7,12β-(OH)<sub>2</sub> and 3,6-(OH)<sub>2</sub> isomers following the application of the dihydroxy isomer filtering tree.</p><h4><strong>Conclusion</strong></h4><p>In conclusion, this study introduces the concept of using a MassQL MS/MS fragmentation-based filtering tree approach to enable precise regio- and stereochemical differentiation of bile acid isomers, which were subsequently validated against reference standards. The method expands the ability to annotate bile acids and has led to the discovery of bile acid deoxycholyl-<i>N</i>-acetyl-putrescine, which had previously been detected in the feces of carnivores but not structurally characterized. By making annotated MS/MS spectra publicly available and enabling the MassQL queries, this approach enhances bile acid analysis, offering innovative tools for exploring their metabolic roles and biological significance, including retro-analysis of regio- and stereochemical isomer variations in existing public LC-MS/MS data.</p></div>

MS/MS Mass Spectrometry Filtering Tree for Bile Acid Regio- and Stereoisomer Annotation

<p><strong>This study investigates nutrient exchange between lunar and martian regolith simulants and bioregenerative life support system (BLiSS) effluent. Using ICP-OES, sorption and dissolution processes were quantified, revealing significant release of elements such as S, Ca, Mg, and Na from the simulants.</strong></p><p>Surface and structural analyses confirmed elemental bonding and mineral alterations after reaction. The findings demonstrate that regolith can supply essential nutrients to BLiSS systems, supporting sustainable agriculture in extraterrestrial environments and highlighting the importance of realistic effluent simulations.</p><blockquote><h4><strong>The original article</strong></h4><h4><a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsearthspacechem.5c00267"><strong>Lunar and Martian Regolith Simulants Desorb and Weather after Exposure to Bioregenerative Life Support System Effluent</strong></a></h4><p>Harrison R. Coker, Daniella Saetta, Misle M. Tessema, Jackson L. Smith, Charles A. Richardson-Gongora, Jason A. Fischer, Hannah I. Roberts, Luke B. Roberson, and Julie A. Howe*</p><p>ACS Earth Space Chem. 2026, 10, 2, 441–454</p><p><a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.1021/acsearthspacechem.5c00267">https://doi.org/10.1021/acsearthspacechem.5c00267</a></p><h6>licensed under <a target="_blank" rel="noopener noreferrer" href="https://creativecommons.org/licenses/by/4.0/"><strong>CC-BY 4.0</strong></a></h6></blockquote><p><strong>Selected sections from the article follow. Formats and hyperlinks were adapted from the original.</strong></p><div><div><h5><strong>Background</strong></h5><p>Inorganic nutrient solutions (e.g., Hoagland’s <a href="javascript:void(0);">(1)</a>) are useful for growing plants in soilless systems but require continuous nutrient inputs that are consumed as plants grow. With future plans for lunar and Mars settlements, dependency on Earth-sourced fertilizers will hinder efficient operations. Therefore, extracting nutrients from regolith to enhance sustainable agricultural operations, or improving the regolith’s fertility such that plants directly derive nutrients from the regolith, are both effective strategies that support diverse cropping operations to produce food and fiber resources through in situ resource utilization (ISRU). <a href="javascript:void(0);">(2,3)</a> Broadly, approaches that utilize surface resources from the Moon and Mars to reduce inputs from Earth are deemed ISRU. <a href="javascript:void(0);">(4)</a></p></div><div><h5><strong>In Situ Resource Utilization</strong></h5><p>The extraction of raw elements from regolith is a primary goal of ISRU. <a href="javascript:void(0);">(4)</a> Various approaches for enhanced dissolution of regolith have been studied, <a href="javascript:void(0);">(5)</a> including techniques such as ionic liquids, <a href="javascript:void(0);">(6)</a> eutectic salts, <a href="javascript:void(0);">(7)</a> electro-deoxidation, <a href="javascript:void(0);">(8)</a> and heat treatment. <a href="javascript:void(0);">(9)</a> While promising, these approaches have the downfall of requiring exogenous chemicals, energy, and technology. Alternatively, a basic approach will encompass using resources such as BLiSS effluent to physically weather the regolith. Because of the underlying basaltic mineralogy of lunar and martian regoliths, hydrologic weathering may be a rapid process that deserves further investigation.<named-content></named-content></p></div><div><h5><strong>Bioregenerative Life Support Systems</strong></h5><p>To recycle consumed nutrients from undesirable plant and human wastes, the use of bioregenerative life support systems (BLiSS) that decompose organic matter into inorganic nutrient streams will be used. <a href="javascript:void(0);">(10)</a> Organic wastes (e.g., plant material, human wastes, etc.) generated by lunar and martian astronauts will necessitate recycling via a series of BLiSS bioreactors that result in effluent streams of water, inorganic nutrients, and metabolites of anerobic digestion, which include various volatile organic acids. <a href="javascript:void(0);">(11)</a> A working BLiSS prototype at Kennedy Space Center (KSC), called the organic processing assembly (OPA), utilizes dual-stage anerobic bioreactors and membrane filtration <a href="javascript:void(0);">(12,13)</a> to accomplish decomposition of organic matter, which is subsequently fed to a phototrophic membrane bioreactor <a href="javascript:void(0);">(14)</a> for the complete oxidation of N species. The microbiome of OPA varies across reactors as a function of varying inputs and substrate decomposition. <a href="javascript:void(0);">(15)</a> While OPA is a developing technology in both biological processing and technological command, analogous BLiSS, will be required to create a circular economy of nutrients in space. <a href="javascript:void(0);">(16)</a> Because BLiSS produces nutrient streams that differ from those of inorganic nutrient solutions, investigating fundamental interactions of BLiSS effluent with regolith simulants will help guide future planning and determine uses of effluent for outposts on the Moon and Mars. In this study, effluent from the OPA at KSC was utilized, as it is a high-fidelity prototype of what may be produced in spaceflight and on lunar and martian outposts.</p></div><div><h5><strong>Lunar and Martian Regolith</strong></h5><p>Lunar regolith is relatively homogeneous in elemental composition, with the major difference being the abundance of Ca. A useful classification refers to lunar samples as being “high-Ca” or “low-Ca” above or below 13.5 wt % CaO. <a href="javascript:void(0);">(17)</a> Increasing abundance of nanophase Fe, along with decreasing grain size, is characteristic of more mature lunar regolith. <a href="javascript:void(0);">(18)</a> Lunar samples exhibit low electrical conductivity (EC), though the electrical properties of lunar regolith are especially sensitive to thermal and atmospheric changes. <a href="javascript:void(0);">(19,20)</a> In general, the chemical reactivity of lunar regolith to organic molecules is not well understood, <a href="javascript:void(0);">(21)</a> but as aqueous and oxidizing environments are introduced to support plant life, it should be expected that lunar regolith will drastically change. For instance, exposure to water vapor increases the adsorption of N<sub>2</sub> and Ar, <a href="javascript:void(0);">(22)</a> while the crushing of regolith promotes the movement of trapped vaporous gases into solution. <a href="javascript:void(0);">(23)</a> Lunar simulants have additionally demonstrated increased generation of reactive oxygen species (ROS) (e.g., H<sub>2</sub>O<sub>2</sub> and OH<sup>–</sup>) in micromolar quantities when crushed and exposed to the atmosphere. <a href="javascript:void(0);">(24)</a> Lunar regolith contains up to 70% agglutinates by volume, <a href="javascript:void(0);">(25)</a> which are aggregates of mineral/lithic fragments fused together by rapid melting and cooling of glass after meteoroid impacts. Agglutinates are noted to have differing abundances of nanophase Fe<sup>0</sup>, with several hypotheses accounting for their incorporation into the lunar regolith. <a href="javascript:void(0);">(26)</a></p><p>Martian astronauts will have greater accessibility to specific and diverse minerals for ISRU than lunar astronauts. For Mars, there is likely a semiactive hydrologic cycle of hydrated brines <a href="javascript:void(0);">(27−30)</a> that may even support microbial life. <a href="javascript:void(0);">(31)</a> Although glass is a more common feature of lunar regolith, in analog martian sites on Earth, glass-matrices have been identified as the possible profile-controlling minerals. <a href="javascript:void(0);">(32)</a> Martian regolith is high in Fe metal oxides, <a href="javascript:void(0);">(33)</a> chloride, <a href="javascript:void(0);">(34)</a> and sulfate salts, <a href="javascript:void(0);">(35)</a> including perchlorates (ClO<sub>4</sub><sup>–</sup>) and other oxidants, such as hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>), which occur at toxic levels for plants. These salts may limit bioavailability of various metals. <a href="javascript:void(0);">(36)</a> Oxidized nitrogen species, simple organics, oxychlorine phases, and sulfates are widespread, with phyllosilicates and carbonates occurring in select Gale Crater materials, and it appears that geochemical conditions and organic C may have once been favorable for microbial life. <a href="javascript:void(0);">(37,38)</a> Recent evidence from the Phoenix landing site quantified organic C at 83–1484 μg C g<sup>–1</sup> and carbonates from 1.1 to 2.6 wt %. <a href="javascript:void(0);">(39)</a> At Gale Crater, the 2007 Phoenix Mars Scout Mission’s Wet Chemistry Laboratory (WCL) conducted in situ experiments at the Phoenix landing site and found solutions were dominated by ClO<sub>4</sub><sup>–</sup>, Mg<sup>2+</sup>, and Na<sup>+</sup>, at mM levels, with sub-mM concentrations of Ca<sup>2+</sup>, K<sup>+</sup>, and Cl<sup>–</sup> and a pH of 7.7.<sup>34</sup> The minimal leachable ions from surface samples had a corrected electrical conductivity (EC) ranging from 1370 to 1900 μS cm<sup>–1</sup> at 25 °C. As the WCL extraction cell measured soil extracts at 1:25 (solid/solution), the reported EC values would likely be 5–25 times higher using traditional soil approaches (saturated paste extract; 1:1–1:5), indicating a highly saline soil that will need to be remediated prior to being used as a plant growth substrate, of which leaching with BLiSS solutions may be an effective management strategy.</p><h4><strong>Methods</strong></h4><h5><strong>Analyses</strong></h5><p>After the 24 h batch experiment, the pH and electrical conductivity (EC) of the reacting solutions were measured to assess changes to solution chemistry after weathering. Solutions were acidified to 1% HNO<sub>3</sub> and analyzed via inductively coupled plasma-optical emission spectroscopy <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library?mainauthorItems=3&amp;search=iCAP+7000"><strong>(ICP-OES) (Thermo Scientific, iCAP 7000)</strong></a> in duplicate. Ion chromatography was used to analyze the ions without any sample preparation. Substrate samples were Au sputter-coated (Denton Vacuum, Desk IV) and mounted prior to scanning electron microscope-energy dispersive X-ray spectroscopy (SEM-EDS) (Jeol, JSM-IT800). <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/products/2166"><strong>X-ray photoelectron spectroscopy (XPS) (Thermo Scientific, Nexsa G2)</strong></a> was used on substrates to identify elemental bonding associations by using <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/products/1489"><strong>Qtegra software</strong></a>. XPS data were processed in the Avantage Data System. X-ray diffraction (XRD) (Malvern Panalytical, Empyrean) was used to assess mineralogical changes to substrates and was performed using Bragg–Brentano mode. The diffraction data were recorded from 15 to 70 two-theta (2θ) degrees. HighScore curve fitting software was used to process the diffraction pattern and compared to the PDF-4+2023 International Center of Diffraction Database (ICDD).</p><h4><strong>Results</strong></h4><h5><strong>Weathering of Substrates</strong></h5><p>Visual observations of the substrates after the batch experiment revealed weathering to the minerals. In JSC-1A, the sharp mineral edges appeared to have some rounded-off features that reduced the overall sharpness of corners and edges (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsearthspacechem.5c00267#fig5">Figure 5</a>); however, a quantitative analysis was not available to indicate if mineral sharpness was statistically reduced. In general, the overall particle size was not substantially reduced in a survey of all of the minerals. Notable artifacts of the weathering process include holes in the mineral faces where small particles collapsed and the appearance of webbing patterns in the anorthosite fraction of JSC-1A. Unfortunately, EDS was not able to detect any sorbed elements in these features (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsearthspacechem.5c00267#fig6">Figure 6</a>). Because the detection limits of EDS are ∼1000 mg kg<sup>–1</sup>, it is reasonable that no sorbed features were detected, given that measured sorption densities after batch experimentation were lower than EDS detection limits. Further, the probed volume at a given electron energy is below the surface, whereas adsorbents are likely only located on the mineral surface.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ACS_Earth_Space_Chem_2026_10_2_441_454_Figure_5_Lunar_simulant_JSC_1_A_imaged_with_scanning_electron_microscope_SEM_9c6a2aac87.jpg" alt="ACS Earth Space Chem. 2026, 10, 2, 441–454: Figure 5. Lunar simulant JSC-1A imaged with scanning electron microscope (SEM). The electron beam energy ranged from 1 to 3 kV. The Hoagland’s and effluent images are after the 24 h batch experiment." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ACS_Earth_Space_Chem_2026_10_2_441_454_Figure_5_Lunar_simulant_JSC_1_A_imaged_with_scanning_electron_microscope_SEM_9c6a2aac87.jpg 245w," sizes="100vw" width="2000" height="1077"></p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ACS_Earth_Space_Chem_2026_10_2_441_454_Figure_6_Scanning_electron_microscope_SEM_image_of_erosion_spots_on_lunar_simulant_JSC_1_A_after_batch_experiment_7c38902bc6.jpg" alt="ACS Earth Space Chem. 2026, 10, 2, 441–454: Figure 6. Scanning electron microscope (SEM) image of erosion spots on lunar simulant JSC-1A after batch experiment. Electron dispersive spectroscopy (EDS) was used to investigate the elemental abundance of erosion regions and was set to 30 keV." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ACS_Earth_Space_Chem_2026_10_2_441_454_Figure_6_Scanning_electron_microscope_SEM_image_of_erosion_spots_on_lunar_simulant_JSC_1_A_after_batch_experiment_7c38902bc6.jpg 245w," sizes="100vw" width="2083" height="1199"></p><h5><strong>Chemical Interaction</strong></h5><p>The elements C, N, P, and Ca were investigated with high-resolution XPS. For C, a major peak at ∼286 eV was observed in all substrates and solutions that corresponded to C–O bonding. Hoagland’s and effluent did not affect the XPS spectra significantly in JSC-1A; however, in MGS-1, there was a notable increase in the Hoagland’s and effluent-treated regolith at ∼294 eV, which corresponds to CF<sub>3</sub> (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsearthspacechem.5c00267#fig9">Figure 9</a>). Because F was not quantified, it is difficult to know if F was in differing concentrations between solutions. Hoagland’s was made from DI water and effluent processes a mixture of fecal simulant and tap water; it is unlikely that F was greater in Hoagland’s.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ACS_Earth_Space_Chem_2026_10_2_441_454_Figure_9_Carbon_C_1s_peaks_of_lunar_JSC_1_A_and_martian_MGS_1_simulants_as_unaltered_materials_and_after_batch_experiment_using_XPS_82622dd14c.jpg" alt="ACS Earth Space Chem. 2026, 10, 2, 441–454: Figure 9. Carbon (C 1s) peaks of lunar (JSC-1A) and martian (MGS-1) simulants as unaltered materials and after batch experiment using XPS." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ACS_Earth_Space_Chem_2026_10_2_441_454_Figure_9_Carbon_C_1s_peaks_of_lunar_JSC_1_A_and_martian_MGS_1_simulants_as_unaltered_materials_and_after_batch_experiment_using_XPS_82622dd14c.jpg 245w," sizes="100vw" width="2079" height="980"></p><h4><strong>Conclusion</strong></h4><p>The hydrologic weathering of lunar and martian regolith simulants by BLiSS streams demonstrated increased plant essential nutrients and metals in solution due to highly soluble compounds and easily weatherable mineralogy. Multielement competitive sorption demonstrates low removal of P and K, but high supplementation of Ca, Mg, and S to the solution. The mechanistic differences between the organic BLiSS effluent and the inorganic nutrition solution were predominantly unaccounted for. It stands to reason that longer-term studies may follow up with the provided results to fully determine how supplementation of BLiSS solutions can be obtained from weathering of the regolith. Therefore, further experimentation that improves upon the extraction of elements of interest and increases the reaction time will be useful in fortifying the sustainability of human operations. The hydrologic weathering of sharp mineral edges also deserves quantitative investigation over time to understand whether reducing the abrasiveness of regolith offers an additional aspect of using BLiSS effluent on lunar and martian surface minerals.</p></div></div>

Lunar and Martian Regolith Simulants Desorb and Weather after Exposure to Bioregenerative Life Support System Effluent

<p><strong>In the week of April 6, the following webinars await you in the field of gas / solid phase and especially Raman, FTIR, GC and GC/MS.</strong></p><blockquote><h4><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinars"><strong>👉 DETAILS AND REGISTRATION IN THE WEBINARS SECTION</strong></a></h4><p><strong>👉 Search and filter in the largest global database</strong> with over <strong>5 500 GC, LC, MS and spectroscopy webinars</strong>.</p></blockquote><div><div><div><div><div><div><h5><strong>1. Bruker: Advances in AFM for the Characterization of 2D Materials</strong></h5><ul><li>We, 8.4.2026 17:00 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinar/6054">Registration</a></li></ul><p>Explore how AFM enables comprehensive nanoscale characterization of 2D materials. Learn about structural, electrical, and chemical mapping, AFM-IR, and nanomanipulation for device fabrication.</p><h5><strong>2. Agilent Technologies: Mastering Gas Sampling: Valve Fundamentals to ASTM Ready RGA &amp; TOGA Analysis</strong></h5><ul><li>Th, 9.4.2026 08:00 CEST</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinar/6056">Registration</a></li></ul><p>In this session, learn how to achieve reliable permanent gas analysis, starting from proper valve selection and sampling fundamentals.</p></div></div></div></div></div></div>

Webinars LabRulezGCMS Week 15/2026

<p><strong>In the week of April 6, the following webinars await you in the field of liquid phase and especially HPLC and LC/MS.</strong></p><blockquote><h4><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/webinars"><strong>👉 DETAILS AND REGISTRATION IN THE WEBINARS SECTION</strong></a></h4><p><strong>👉 Search and filter in the largest global database</strong> with over <strong>5 500 GC, LC, MS and spectroscopy webinars</strong>.</p></blockquote><h5><strong>1. Waters Corporation: Fit-for-purpose workflows for inositol stereoisomer profiling in dietary supplements and foods using single and tandem mass spectrometry</strong></h5><ul><li>Tu, 7.4.2026 19:00 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/webinar/6030">Registration</a></li></ul><p>The aim of this webinar is to present analytical procedures capable of simultaneously separating and quantifying free inositol stereoisomers in both simple matrices and complex matrices.</p><h5><strong>2. Thermo Fisher Scientific: Transforming Fuel Testing Performance with Combustion Ion Chromatography</strong></h5><ul><li>We, 8.4.2026 07:00 CEST</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/webinar/6093">Registration</a></li></ul><p>Join us for an interactive session on how Combustion Ion Chromatography (C-IC) is transforming fuel testing performance in modern laboratories.</p><h5><strong>3. SCIEX: Getting started with LC-MS/MS for PFAS</strong></h5><ul><li>We, 8.4.2026 10:00 CEST</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/webinar/6102">Registration</a></li></ul><p>Learn how to build LC-MS/MS methods for PFAS analysis, achieve ultra-low detection limits, and gain practical skills for environmental and food testing in this expert-led webinar.</p><h5><strong>4. Phenomenex: Extraction Face-Off: Choosing Between SLE and SPE</strong></h5><ul><li>We, 8.4.2026 10:00 CEST</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/webinar/6092">Registration</a></li></ul><p>Understand how SLE and SPE work and how they are different from each other.</p><h5><strong>5. Waters Corporation: RADIAN™ ASAP Mass Spectrometry for the Detection and Analysis of Explosive Traces</strong></h5><ul><li>We, 8.4.2026 16:00 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/webinar/6031">Registration</a></li></ul><p>Explore how mass spectrometry enables rapid detection of trace explosives. Learn how RADIAN™ ASAP extends forensic and security workflows, supporting future screening technologies and ion-mobility innovation.</p><h5><strong>6. Technology Networks: Label Free Quantitation: New Insights Into High-Throughput Proteomic Workflows</strong></h5><ul><li>Th, 9.4.2026 16:00 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/webinar/5969">Registration</a></li></ul><p>Discover how next-generation LC–MS and the ZenoTOF 8600 enable robust, high-throughput LFQ proteomics, backed by insights from a large multi-laboratory benchmark study.</p>

Webinars LabRulezLCMS Week 15/2026

<p><strong>In the week from April 6, the following webinars await you in the field of atomic and molecular spectroscopy and spectrometry</strong></p><blockquote><h4><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/webinars"><strong>👉 DETAILS AND REGISTRATION IN THE WEBINARS SECTION</strong></a></h4><p><strong>👉 Search and filter in the largest global database</strong> with over <strong>5 500 GC, LC, MS and spectroscopy webinars</strong>.</p></blockquote><h5><strong>1. Agilent Technologies: REE determination in waste water and effective doubly charged interference removal by ICP-MS</strong></h5><ul><li>Tu, 7.4.2026 20:30 CEST</li><li><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/webinar/6045">Registration</a></li></ul><p>Explore strategies to mitigate REE-related spectral interferences in wastewater analysis by ICP-MS, focusing on doubly charged ions and robust workflows for ultra-trace detection.</p><h5><strong>2. Milestone: Sustainable Sample Preparation</strong></h5><ul><li>We, 8.4.2026 16:00 CEST</li><li><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/webinar/6094">Registration</a></li></ul><p>Learn how to make sample preparation more sustainable using microwave digestion, DMA, and GreenPrep MW Score. Join this webinar for practical strategies and greener workflows.</p><h5><strong>3. Bruker: Advances in AFM for the Characterization of 2D Materials</strong></h5><ul><li>We, 8.4.2026 17:00 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/webinar/6054">Registration</a></li></ul><p>Explore how AFM enables comprehensive nanoscale characterization of 2D materials. Learn about structural, electrical, and chemical mapping, AFM-IR, and nanomanipulation for device fabrication.</p>

Webinars LabRulezICPMS Week 15/2026

<p><strong>Our Library never stops expanding. What are the most recent contributions to LabRulezGCMS Library in the week of 6th April 2026? Check out new documents from the field of the gas phase, especially GC and GC/MS techniques!</strong></p><blockquote><p><span style="font-size:20px;">👉 </span><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library"><span style="font-size:20px;"><strong>SEARCH THE LARGEST REPOSITORY OF DOCUMENTS ABOUT GCMS AND RELATED TECHNIQUES</strong></span></a></p></blockquote><blockquote><p><strong>👉 Need info about different analytical techniques?</strong> Peek into <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library"><strong>LabRulezLCMS</strong></a> or <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library"><strong>LabRulezICPMS</strong></a> libraries.</p></blockquote><p>This week we bring you application notes by <strong>Agilent Technologies, BaySpec, </strong>poster by <strong>MDCW / William &amp; Mary </strong>and<strong> </strong>brochure by<strong> Shimadzu!</strong></p><h3><strong>1. Agilent Technologies: High-Throughput BTEX Analysis in Nail Products by SPME and GC/TQ</strong></h3><p><strong>Minimal steps, maximum precision</strong></p><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/an_btex_analysis_nail_products_spme_gctq_5994_9009en_agilent_24ef32dd13.pdf"><strong>Full PDF for download</strong></a></li></ul><p>BTEX compounds—benzene, toluene, ethylbenzene, and xylenes—are volatile aromatic hydrocarbons widely used as solvents in industrial and consumer products. Among these, toluene is the most prevalent in nail polish formulations, where it serves as a solvent to dissolve resins and pigments, ensuring smooth application, uniform color dispersion, and rapid drying. Historically, these properties made toluene a preferred ingredient in nail coatings, including traditional polishes, gel formulations, and nail art products. However, its inclusion presents challenges for regulatory compliance and product reformulation. In response to these challenges, the California Department of Toxic Substances Control (DTSC) has listed nail products containing toluene as Priority Products under the Safer Consumer Products Regulations.1 Manufacturers selling such products in California must submit a Priority Product Notification and conduct an Alternative Analysis if toluene concentrations exceed the 100-ppm threshold.&nbsp;</p><p>To support compliance and ensure accurate monitoring of BTEX levels in nail products, robust analytical methods are essential. Solid phase microextraction (SPME) coupled with gas chromatography/triple quadrupole mass spectrometry (GC/TQ) has emerged as a preferred approach for volatile organic compound analysis due to its solvent-free sample preparation, high sensitivity, and compatibility with complex cosmetic matrices. The 8890 GC with 7000 Series GC/TQ offers enhanced detection capabilities through dynamic multiple reaction monitoring (dMRM), enabling precise quantification of BTEX compounds at trace levels, below regulatory thresholds. This platform provides the analytical rigor required for method validation, including limits of detection, recovery, and precision, ensuring compliance with California's stringent performance criteria and supporting industry efforts toward improving consumer product&nbsp;quality.&nbsp;</p><h4><strong>Experimental</strong></h4><h5><strong>GC/TQ analysis&nbsp;</strong></h5><p>Analyses were performed on an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=8890+GC"><strong>8890 GC</strong></a> coupled to a <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=7000"><strong>7000 Series GC/TQ </strong></a>equipped with an EI extractor ion source (Figure 2). The instrument operating parameters are listed in Table 2. The system was operated in splitless mode with an inlet temperature of 200&nbsp;°C, a purge flow of 3 mL/min, and a purge flow to split vent of 50&nbsp;mL/min at 2&nbsp;minutes. Carrier gas was helium at a constant flow of 0.693&nbsp;mL/min with a total flow of 53.7 mL/min. The chromatographic separation was accomplished on an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=DB-624+Ultra+Inert+column"><strong>Agilent J&amp;W DB-624 Ultra Inert column</strong></a> (20&nbsp;m × 0.18&nbsp;mm, 1&nbsp;µm, part number 121-1324UI). The oven program started at 40&nbsp;°C (hold 2&nbsp;minutes), ramped at 35&nbsp;°C/min to 160&nbsp;°C, and held for 2.58&nbsp;minutes, giving a total run time of 8.0&nbsp;minutes. The transfer line was maintained at 230&nbsp;°C, with the ion source at 230&nbsp;°C and quadrupoles at 150&nbsp;°C.</p><h4><strong>Conclusion&nbsp;</strong></h4><p>A rapid, high-throughput headspace‑SPME GC/TQ method was developed for quantifying BTEX in nail product matrices, using a 100-µm PDMS Agilent Smart SPME fiber on an Agilent 8890 GC with Agilent 7000 Series GC/TQ. The method provides solvent-free extraction, 8-minute chromatographic runs, and an ~11-minute total cycle time, enabling high-throughput analysis with robust selectivity in dMRM mode. Quality control results demonstrated mean recoveries of 100 to 107% with RSDs ≤ 8%, meeting method acceptance criteria for compliance-focused testing for toluene. Integration of Smart SPME automation and the intelligent features of the 8890 GC and 7000 Series GC/TQ allows a practical, defensible solution for routine laboratories monitoring BTEX in nail products. Calibration performance showed high linearity and low variance across the working ranges, with all compounds meeting initial calibration criteria via R² ≥ 0.995 or average RF RSD ≤ 20%. Combined with the short cycle time and automated fiber tracking, this workflow is ideally suited for routine compliance testing of BTEX in nail products using the 8890 GC and 7000&nbsp;Series GC/TQ.</p><h3><strong>2. BaySpec: Detection of residual pesticides on fruits and vegetables using Portability miniature mass s pectrometer</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/Bay_Spec_App_Note_Portability_Pesticides_4a7311fb3e.pdf"><strong>Full PDF for download</strong></a></li></ul><p>Pesticides are used in a variety of different ways during the production of food. Ranging from preventing crop damage by insects, rodents and molds during growth to prolonging storage of food after harvest. Because of the frequent usage, the residual pesticides are often found in many agricultural products and their monitoring and control is an important step in achieving and maintaining overall food safety in the modern society.&nbsp;</p><p>Mass spectrometry in connection with different separation techniques currently represents the main analytical approach for determination of residual pesticides in food. Traditionally, samples need to be collected and send to a laboratory for analysis using techniques such as GC-MS or HPLC-MS, which are costly and time-consuming. In addition, the conventional mass spectrometry usually requires laborious sample pretreatment, which does not allow for immediate in-situ sample determination. Presented here is an application of Thermal Desorption ElectroSpray Ionization (TD-ESI) for pesticide screening coupled to a portable mass spectrometer.&nbsp;</p><p>TD-ESI is a mass spectrometry technique from the family of ambient ionization methods that utilizes very simple probing of different surfaces with no or limited sample pretreatment while it is still noted for its selective and sensitive detection capabilities. In TD-ESI a solid surface or a liquid sample is touched by a simple metallic probe that absorbs the analyte. The probe is then inserted into a heated tube and the desorbed analyte is carried by gas flow into an orthogonally mounted electrospray. The electrospraty plume extracts the analyte and further ionization and ion introduction follows the conventional electrospray mechanism.&nbsp;</p><p><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2219"><strong>Bayspec’s Portability mass spectrometer</strong></a> is less than 10kg highly portable and battery operated linear ion trap mass spectrometer with atmospheric pressure inlet (API). When TD-ESI is combined with PortabilityTM then it is possible to perform fast in-field detection of analytes including residual pesticides, directly of the surfaces of fresh food products without any sample pre-treatment. Fast pesticide screening by Portability mass spectrometer can immediately disclose fake organic food products as well as to discover elevated levels of residual pesticides.&nbsp;</p><p>TD-ESI-MS was used to rapidly screen residual pesticides on the surfaces of different fruits and vegetables. Direct sampling probe was used to introduce analytes from surfaces of unprocessed samples. Due to short analysis times (1-5s a sample), the technique allows for fast screening for applications in food and environmental safety. MS (as well as MS/MS) analyses can be performed on surface-residual pesticides at ppm and sub-ppm levels. The miniaturized TD-ESI ion source compatible with Portability is available from BaySpec. This ion source mounts on the Portability front inlet and does not require any additional support, external power or gases. The simple intuitive software interface is operated by touch screen and makes the instrument extremely easy to control. The external TD-ESI source is fully integrated into the main software environment and the hyphenated system is thus very user-friendly, does not require excessive training and can be operated by persons with no previous mass spectrometry experiences.</p><h3><strong>3. MDCW / William &amp; Mary: Volatile Characterization of American Foulbrood Disease Using Comprehensive Two-Dimensional Gas Chromatography</strong></h3><ul><li>Poster</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/P_15_Christensen_39521e3391.pdf"><strong>Full PDF for download</strong></a></li></ul><p>American foulbrood (AFB) is a deadly disease spread by Paenibacillus larvae bacterial spores, targeting the brood stage of Apis mellifera honey bees. Broods perish in a matter of days after exposure to the spores, forming infected colloidal scales in the hive that adult bees cannot remove. 1,2 The spores are extremely persistent and resistant to typical treatment methods, which standardized the immediate euthanasia of bees and destruction of the hive and associated equipment by burning. 3 In an effort to expedite identification of the spores, scent-detection dogs have been trained for use in apiaries. Furthermore, gammairradiation has been tested as a proposed treatment method as it would offer a nondestructive alternative to sterilization.</p><p>The goals of this study were to use comprehensive two-dimensional gas chromatography – time-of-flight mass spectrometry (GC×GC-TOFMS) to characterize the volatiles associated with AFB disease for understanding scent detection and to measure the effectiveness of gamma-irradiation in sterilizing these volatiles.</p><h4><strong>Methods</strong></h4><p>Samples included blanks, material from healthy comb, aged unsterilized diseased scales, fresh unsterilized diseased scales, and diseased scales sterilized with the proposed treatment method of gamma-irradiation. These samples were stored in headspace vials (Figure 3) in the freezer when not in use. No sample preparation was required before injection with solidphase microextraction using the LPAL-3 (CTC Analytics).</p><p>Analysis was performed using a <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/37"><strong>Pegasus BT4D</strong></a> (LECO Corporation) according to the parameters described below in Table 1. <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/41"><strong>ChromaTOF software</strong></a> (LECO Corporation) was used to analyze the chromatographic data. Preliminary identifications were assigned to peaks using a minimum signal to noise of 200 and a minimum stick count of 3.</p><h4><strong>Conclusions</strong></h4><p>GC×GC-TOFMS can be used to distinguish the volatile profiles of A. mellifera samples at different stages of infection with AFB disease. Future Directions for Research:&nbsp;</p><ul><li>Discrimination of volatiles specific to AFB from non-specific volatiles&nbsp;</li><li>Characterization of AFB-specific volatiles for scent-detection purposes&nbsp;</li><li>Measurement of gamma-irradiation sterilization success in removing AFB volatiles</li></ul><h3><strong>4. Shimadzu: Screening System for Phthalate Esters, Brominated Flame Retardants and Other Regulated Substances Py-Screener Ver.3</strong></h3><ul><li>Brochure</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/c146_e507_45f041b0d7.pdf"><strong>Full PDF for download</strong></a></li></ul><p>The <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=Py-Screener"><strong>Py-Screener™ Ver. 3</strong></a> can screen for 7 types of phthalate esters and brominated flame retardants (PBBs, PBDEs), including substances regulated under the RoHS Directive. In addition, it can also test for PIP (3:1), which is regulated under the US TSCA (Toxic Substances Control Act), as well as UV-328, Dechlorane Plus (DP), and short-chain chlorinated paraffins (SCCPs) and medium-chain chlorinated paraffins (MCCPs), which are regulated under the Stockholm Convention (POPs Convention) on Persistent Organic Pollutants (POPs). These regulated compounds, thermally extracted from the sample by Pyrolysis-GC-MS (Py-GC-MS), are selectively detected and quantified. Py-Screener Ver. 3 consists of dedicated software for easy screening, special standard samples, and a sampling tool kit, making it simple to operate even for first-time users.</p><h5><strong>Shimadzu Corporation’s Solutions for Complying with International Hazardous Substance Regulations</strong></h5><p>When manufacturing and exporting products, it is necessary to comply with the chemical and hazardous substance regulations established by each country. Products contain many parts and use various materials and substances. Therefore, it is the manufacturer’s responsibility to manage the entire supply chain to ensure that harmful substances are not contained. Shimadzu Corporation provides analysis solutions that comply with these regulations.</p><h5><strong>Applicable Systems and Software</strong></h5><ul><li><strong>GC-MS: </strong><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=GCMS-QP2020+NX"><strong>GCMS-QP™2020 NX</strong></a>, <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=GCMS-QP2020"><strong>GCMS-QP2020,</strong></a> <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=GCMS-QP2010+Ultra"><strong>GCMS-QP2010 Ultra</strong></a></li><li><strong>Pyrolyzer:</strong> <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=42&amp;search=EGA%2FPY-3030D"><strong>EGA/PY-3030D</strong></a> multi-shot pyrolyzer</li><li><strong>Autosampler:</strong> AS-2020E, <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=42&amp;search=AS-1020E"><strong>AS-1020E auto-shot sampler&nbsp;</strong></a></li><li><strong>GC-MS Workstation:</strong> <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=GCMSsolution"><strong>GCMSsolution</strong></a>™ (Ver. 4.60SP2 or later) + <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=LabSolutions+Insight"><strong>LabSolutions Insight</strong></a>™ (Ver. 5.0 or later)</li><li><strong>Py Workstation:</strong> EGA-PY3030 program (Ver. 1.54 or later)</li></ul>

News from LabRulezGCMS Library - Week 15, 2026

News from LabRulezLCMS Library - Week 15, 2026

<p><strong>Our Library never stops expanding. What are the most recent contributions to LabRulezICPMS Library in the week of 6th April 2026? Check out new documents from the field of spectroscopy/spectrometry and related techniques!</strong></p><blockquote><p><span style="font-size:20px;">👉 </span><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library"><span style="font-size:20px;"><strong>SEARCH THE LARGEST REPOSITORY OF DOCUMENTS ABOUT SPECTROSCOPY/SPECTROMETRY RELATED TECHNIQUES</strong></span></a></p></blockquote><blockquote><p><strong>👉 Need info about different analytical techniques?</strong> Peek into <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library"><strong>LabRulezLCMS</strong></a> or <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library"><strong>LabRulezGCMS</strong></a> libraries.</p></blockquote><p>This week we bring you application notes by <strong>Metrohm,</strong> <strong>Shimadzu, Thermo Fisher Scientific </strong>and <strong>Waters Corporation!</strong></p><h3><strong>1. Metrohm: Whey permeate analysis with NIRS</strong></h3><p><strong>Monitor dairy production processes easily in seconds</strong></p><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/labrulez-bucket-strapi-h3hsga3/an_nir_144_download_34598659f1.pdf"><strong>Full PDF for download</strong></a></li></ul><p>Whey permeate, a byproduct of manufacturing whey protein powder, contains high amounts of lactose, phosphate, and minerals. Because of its sweet and mild taste, whey permeate is often used in bakeries and chocolate manufacturing. The key to optimizing whey permeate production is to control production streams in real time. It is important to monitor the production process with highthroughput analytical techniques to maximize product yield and ensure high product quality.&nbsp;</p><p>Nearinfrared spectroscopy (NIRS) is a fast, and chemicalfree analysis technique that can support this kind of testing. NIR spectroscopy can measure the most important quality parameters (i.e., protein, lactose, moisture, ash, pH, and phosphate) simultaneously in whey permeate without any sample preparation. The NIRS solution is fast, easy to operate, and can be used atline or offline in a quality control lab.</p><h4><strong>EXPERIMENTAL EQUIPMENT&nbsp;</strong></h4><p>158 whey permeate samples were analyzed on a <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library?mainauthorItems=220&amp;search=NIR+analyzer"><strong>Metrohm NIR Analyzer</strong></a> equipped with a small cup accessory. All measurements were performed in reflection mode (1000–2250 nm). Metrohm software was used for data acquisition and prediction model development.</p><h4><strong>CONCLUSION&nbsp;</strong></h4><p>This Application Note demonstrates the feasibility of using NIR spectroscopy for whey permeate quality control. Near infrared-spectroscopy is a rapid, nondestructive analytical technique that can monitor the production process of dairy products. Aside from the analysis of whey permeate, the whey protein production stream can also be monitored by NIRS.</p><h3><strong>2. Shimadzu: Measurement of Residual Metal Catalysts by X-ray Fluorescence</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/labrulez-bucket-strapi-h3hsga3/an_01_01086_en_4beb25fd1d.pdf"><strong>Full PDF for download</strong></a></li></ul><h4><strong>User Benefits</strong></h4><ul><li><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library?mainauthorItems=1&amp;search=ALTRACE"><strong>ALTRACE</strong></a> can determine levels of heavy metals present in organic compounds at around 1 mg/kg in under 10 minutes per sample.</li><li>Analyzing and managing levels of residual metal catalysts can be performed by simply placing samples in the sample vessel and analyzing them without the need for complex sample pretreatment.</li><li>By increasing the X-ray tube power and optimizing the optical design, the sensitivity of ALTRACE for heavy metals has been<br>dramatically improved compared to the previous model.</li></ul><p>Many industrial products we encounter every day are produced from organic compounds by manufacturing processes that utilize a range ofsynthesisreactions and metal catalysts. Catalysis can be classified as either homogeneous or heterogeneous (although drug and chemical production processes typically use homogeneous catalytic systems). While homogeneous catalysis allows for precise control over catalytic reactions, recovering the catalyst after the reaction can be difficult.&nbsp;</p><p>Nevertheless, managing the levels of residual catalysts in industrial products is critical to ensure safety and because of their high costs. For example, the ICH Q3D Guideline for Elemental Impurities (adopted in April 2017) requires risk assessments when materials such as metal catalysts are added intentionally during a production process.&nbsp;</p><p>Energy dispersive X-ray fluorescence (EDXRF) spectrometry offers a simple but effective technique for assessing the levels of residual metal catalysts. Normally, the lower limit of quantification for EDXRF spectrometric analysis of heavy metals is above 1 mg/kg, which limitsits use in quantitative analysis. However, the <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library?mainauthorItems=1&amp;search=ALTRACE"><strong>ALTRACE</strong></a> is equipped with a high-power X-ray tube that dramatically improves its sensitivity for heavy metals, enabling their determination at 1 mg/kg and below in lessthan 10 minutes. This Application News describes using ALTRACE to determine residual levels of a homogeneous catalyst after a synthesis reaction. The catalyst used in this analysis is palladium (Pd), which is a widely applied heavy metal catalyst, and the reaction catalyzed by the Pd catalyst is a cross-coupling reaction. A metal scavenger and activated carbon were each used to remove the Pd catalyst from the reaction products. Metal scavengers are frequently used in this role, and activated carbon offers a relatively cheap method for removing catalysts.</p><h4><strong>Conclusion&nbsp;</strong></h4><p>Common methods of elemental impurity analysis, such as atomic absorption spectrometry (AAS), ICP atomic emission spectroscopy (ICP-AES), and ICP mass spectrometry (ICP-MS), require liquid samples, so solid and powder samples must be prepared into a solution prior to analysis. However, EDXRF spectrometry can determine levels of elemental impurities regardless of the sample phase or form (solution, powder, etc.), provided the target element is distributed uniformly throughout the sample. The sensitivity of ALTRACE for heavy metals has been substantially improved compared to previous models, allowing for rapid quantitative determination of heavy metals at 1 mg/kg and below. Based on the performance presented in this article, ALTRACE is an effective tool for managing residual levels of metal catalysts.</p><h3><strong>3. Thermo Fisher Scientific: The Raman Spectroscopy of Graphene and the Determination of Layer Thickness</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/labrulez-bucket-strapi-h3hsga3/raman_spectroscopy_graphene_determination_layer_thickness_an52252_29274e8aea.pdf"><strong>Full PDF for download</strong></a></li></ul><p>Currently, a tremendous amount of study is being directed toward graphene. This interest is driven by the novel properties that graphene possesses and its potential use in a variety of application areas that include but are not limited to electronics, heat transfer, bio-sensing, membrane technology, battery technology and advanced composites. Graphene exists as a transparent two-dimensional network of carbon atoms. It can exist as a single atomic-layer thick material, or it can be readily stacked to form stable, moderately thick samples containing millions of layers—a form generally referred to as graphite. However, the interesting properties exhibited by graphene (substantial electrical and thermal conductivity, high mechanical strength, and high optical transparency) are only observed for graphene films that contain only one or a few layers. Therefore, developing technologies and devices based upon graphene’s unusual properties requires accurate determination of the layer thickness for materials under investigation. Raman spectroscopy can be employed to provide a fast, non-destructive means of determining layer thickness for graphene thin films.</p><h4><strong>Instrument considerations&nbsp;</strong></h4><p>There are a few specifications that should be considered when selecting a Raman instrument for graphene characterization. First, since graphene samples are usually very small, selecting a Raman instrument with microscopy capabilities is imperative.</p><p>The next issue to consider is which excitation laser to select. While graphene measurements can be made successfully with any of the readily available Raman lasers, it is also important to consider the substrate that the graphene will be deposited onto. It is common for graphene to be deposited on on either Si or SiO2 substrates, and both of these materials can exhibit fluorescence with near-infrared (NIR) lasers such as 780 nm or 785 nm. For this reason, visible lasers are usually recommended, typically a 633 nm or 532 nm laser.&nbsp;</p><p>Next, since relatively small wavenumber shifts can significantly impact the interpretation of the Raman spectra, it is crucial to have a robust wavelength calibration across the entire spectrum. Using a single point wavelength calibration with some other applications may be sufficient, but this only ensures that one wavelength is calibrated and leaves room for a large margin of error. A multipoint wavelength calibration that is regularly refreshed, such as the standard calibration routine used with <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/products?category=184&amp;manufacturerItems=3&amp;search=dxr3"><strong>Thermo Scientific DXR3 Raman instruments</strong></a>, will provide considerably more confidence in the results. It is also necessary to have an instrument with high wavenumber precision to observe small wavenumber shifts when altering the sample. In fact, small wavenumber shifts can represent changes in the sample rather than represent the variability from the instrument. There is a common myth that it is necessary to utilize high resolution in order to achieve high wavenumber precision. Not only is this incorrect, but a high resolution will actually add considerable noise to the spectrum, which will add to the wavenumber variability. A high degree of wavenumber precision, such as that provided by the <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/products/2239"><strong>Thermo Scientific™ DXR™3 Raman Microscope</strong></a>, will significantly improve data confidence even when you are evaluating band shifts from low levels of strain or doping. It is also important to have exact control of your laser power at the sample and be able to adjust that laser power in small increments. This is important to control temperature-related effects and to provide flexibility to maximize Raman signal while still avoiding sample heating or damage from the laser. The DXR3 Raman systems are equipped with a unique device called a laser power regulator, which maintains laser power with unprecedented accuracy and provides exceptional ability to fine-tune laser power and optimize it for each experiment.<sup>1</sup>&nbsp;</p><p>Lastly, the Raman microscope must have an automated stage and associated software to generate detailed Raman point maps. As will be seen in the next section, Raman point mapping or imaging extends the single point measurement to assess a sample’s layer thickness uniformity. The <strong>Thermo Scientific OMNIC™ Software</strong> suite contains powerful mapping and processing tools that diminish the complexity of collecting highly detailed maps and interpreting their results.</p><h4><strong>Conclusions&nbsp;</strong></h4><p>Raman spectroscopy is an excellent tool for the characterization of graphene and layer thickness. Few techniques will provide as much information about the structure of graphene samples as Raman spectroscopy, and any lab doing graphene characterization without Raman would be at a significant disadvantage. The DXR3 Raman Microscope is an ideal Raman instrument for graphene characterization because it can provide the high level of stability, control, and sensitivity needed to produce confident results.</p><h3><strong>4. Waters Corporation: See What’s Really in Your Formulation with Backgrounded Membrane Imaging</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/labrulez-bucket-strapi-h3hsga3/720009098_en_5d36d71789.pdf"><strong>Full PDF for download</strong></a></li></ul><p>Protein aggregation in therapeutic protein products can induce adverse immunogenic responses in patients<sup>1–4</sup> . Per the FDA’s recommendations, “strategies to minimize aggregate formation should be developed as early as feasible in product development”<sup>5</sup> and “an assessment should be made of the range and levels of subvisible particles (2–10 µm) present in therapeutic protein products initially and over the course of the shelf life”.<sup>5</sup> Yet, accurate subvisible protein aggregation analysis has remained elusive to protein drug formulators since current subvisible analyzers are not sensitive enough to measure protein aggregates effectively. In this application note, we explore how backgrounded membrane imaging (BMI), a high refractive index contrast technique used by the HORIZON particle analysis system, performs highly sensitive measurements of subvisible protein aggregates in the 2 µm–4 mm size range, enabling 30% higher reproducibility compared to flow imaging.</p><h4><strong>Conclusion&nbsp;</strong></h4><p>When studying the impact of protein aggregate refractive index, IgG protein aggregates analyzed on both the<strong> </strong><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library?mainauthorItems=5&amp;search=HORIZON"><strong>HORIZON® instrument</strong></a> and flow imager systems produced equivalent particle count trends. However, the HORIZON® system was more sensitive (measured more overall counts) and had overall lower variability with average CVs of 14.4% compared to the flow imager which produced average CVs of 20.1%. The differences in variability and counts were most pronounced at lower concentrations and size range respectively. Given that most particles in a therapeutic drug formulation are small, the inability of flow imagers to accurately count the smallest of protein aggregates has a dramatic impact on the total number of particles measured. This can mean an undercounting by as much as 3–10X depending on the protein and formulation conditions.&nbsp;</p><p>High variability at low concentrations in flow imagers can pose a hurdle for early stage analysis were sample is scarce. In low volume analysis (&lt;250 µL), the possibility of measuring fewer particles increases, therefore it is imperative to have high sensitivity measurements when already challenged by low sampling statistics.&nbsp;</p><p>In the excipient effect study, sucrose did not have an impact on the overall particle counts when measured using the HORIZON® system. This contrasts with previous studies comparing excipient effects on three flow imagers.10 In each case, the particle counts decreased up to 30% or more using standard sucrose formulation concentrations of 0–20%. The difference between the data generated by BMI and FI can be attributed to the fact that the HORIZON® instrument is not affected by particle or solution refractive index.&nbsp;</p><p>Flow imagers are deeply vulnerable to the impact of refractive index when measuring protein aggregates due to their translucency and the negative impact of surfactants. Due to this basic optical phenomenon, flow imagers can dramatically undersize and undercount particles. Finding the right tool for the job will have a critical impact on data accuracy and sensitivity. Powered with BMI, the HORIZON® system provides high refractive index contrast analysis to enable accurate, robust, and sensitive subvisible particle counting from 2 µm–4 mm in as little as 25 µL of sample and 96 samples in under 2 hours.</p>

News from LabRulezICPMS Library - Week 15, 2026

<p><strong>In the week of April 13, the following webinars await you in the field of gas / solid phase and especially Raman, FTIR, GC and GC/MS.</strong></p><blockquote><h4><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinars"><strong>👉 DETAILS AND REGISTRATION IN THE WEBINARS SECTION</strong></a></h4><p><strong>👉 Search and filter in the largest global database</strong> with over <strong>5 500 GC, LC, MS and spectroscopy webinars</strong>.</p></blockquote><div><div><div><div><div><div><h5><strong>1. Agilent Technologies: The Journey of Safer Science through Safer Labs</strong></h5><ul><li>Tu, 14.4.2026 07:30 CEST</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinar/6104">Registration</a></li></ul><p>Agilent Safer Labs webinar highlights best practices in lab safety, including handling, storage, and instrumentation, helping professionals build safer, more efficient laboratory environments.</p><h5><strong>2. Agilent Technologies: Column Confidence: Making the Right Choice for Your GC Needs</strong></h5><ul><li>Tu, 14.4.2026 17:00 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinar/5725">Registration</a></li></ul><p>Learn how to choose the right GC or GC/MS column by understanding stationary phase chemistry and column dimensions. Improve selectivity, peak behavior, and resolution for a more robust analysis.</p><h5><strong>3. Metrohm: Measure smarter, spend less – NIR spectroscopy for polymer analysis</strong></h5><ul><li>Th, 16.4.2026 15:00 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinar/6032">Registration</a></li></ul><p>Discover how NIR spectroscopy enables fast, chemical-free polymer analysis. Learn how manufacturers can streamline quality control, reduce waste, and improve efficiency with rapid multi-parameter measurements.</p><h5><strong>4. C&amp;EN: Precision Lab Solutions for High-End Optics and Coatings</strong></h5><ul><li>Th, 16.4.2026 17:00 CEST</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinar/6096">Registration</a></li></ul><p>Join this presentation and open discussion with industry-leading experts Patrick Muller and Kieran Evans – leaders in UV/Vis and IR analytical methods and testing techniques.</p></div></div></div></div></div></div>

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