Size distribution and elemental analysis of fine particles from Li-ion battery cell fire

A team from CEITEC Masaryk University (MUNI) in collaboration with researchers from two research institutes in Norway has, for the first time, captured how echovirus 18, a member of the enterovirus genus, releases its genetic material into cells to initiate infection. The study provides a structural view of an early stage of viral infection under near-native conditions. Using cryo-electron microscopy, the researchers discovered that the virus does not release its RNA through a small pore in its capsid, as had long been assumed. Instead, its protein shell partially disassembles, creating a large opening through which the viral genetic material escapes into the host cell. A detailed understanding of this genome release mechanism could eventually help develop compounds preventing enteroviruses from infecting cells.Enteroviruses are common human pathogens causing diseases ranging from the common cold and gastrointestinal infections to severe neurological disorders. Echovirus 18, the virus investigated in this study, is known primarily as a cause of meningitis and encephalitis in children. It belongs to the picornaviruses, a family of small, non-enveloped viruses whose genetic material is protected by a protein shell, the capsid, organized with icosahedral symmetry.To replicate within a cell, the enteroviruses must release their RNA – the molecule that carries viral genetic information – from the capsid, into the cell cytoplasm. Although this step is crucial for initiating infection, it has never been observed in infected cells.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/CEITEC_Vedci_z_CEITEC_jako_prvni_zachytili_jak_enteroviry_spousteji_infekci_bunek_71d553bb0e.jpg" alt="CEITEC/Plevka Lab: CEITEC Scientists Are the First to Capture How Enteroviruses Initiate Infection: View into a cell infected by echovirus 18. Echovirus 18 is shown in green and yellow, ribosomes in violet, and actin filaments in cyan. Scale 50 nm. " srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_CEITEC_Vedci_z_CEITEC_jako_prvni_zachytili_jak_enteroviry_spousteji_infekci_bunek_71d553bb0e.jpg 221w," sizes="100vw" width="1600" height="1128">“For a long time, two main theories existed about how picornaviruses deliver their RNA genomes into cells. One proposed that the genome leaves the capsid through a small opening. The other, supported by earlier work from our laboratory, suggested that the genome escapes from partially disassembled capsids missing pentamers of capsid proteins. However, both models were based on experiments with virus particles outside cells. We wanted to go one step further and see what really happens during infection inside a cell,” says <a target="_blank" rel="noopener noreferrer" href="https://www.ceitec.eu/liya-mukhamedova-ph-d/u89248?page=publication">Liya Mukhamedova</a>, the study’s first author from CEITEC MUNI.Using cryo-electron microscopy, which allows scientists to visualize biological structures at exceptionally high resolution, the researchers observed individual echovirus 18 particles directly within infected cells. They discovered that empty virus particles in infected cells lack parts of their capsids. It is through these openings that the virus releases its RNA.The study also revealed the role of the FcRn receptor, a cell-surface molecule that enteroviruses use to enter cells. The binding of the virus to the receptor triggers structural changes in the viral particle that prime it for subsequent genome release. The team showed that receptor binding causes the loss of the so-called pocket factor, a small molecule that normally helps stabilize the virus particle. The virus otherwise remains largely intact, suggesting that receptor binding is only the first step toward uncoating, while additional factors within the cell are required to complete the process and trigger genome release.“Infection is a complex process, during which enterovirus particles sense various interactions with cell components. The binding of echovirus 18 to the FcRn host-cell receptor triggers conformational changes in the virus, priming it for genome release.” – explains <a target="_blank" rel="noopener noreferrer" href="https://www.ceitec.eu/pavel-plevka-ph-d/u26854">Pavel Plevka</a>, head of the Structural Virology Research Group.The researchers did not observe the so-called activated particles that are key intermediates in the enterovirus uncoating process. This suggests that genome release in cells occurs much faster than previous experiments had suggested.By combining structural data obtained from studies of virus particles outside living cells with observations of infected cells, the study offers a picture of how enterovirus infection begins. Moving beyond simplified experiments with isolated virus particles, it brings scientists closer to understanding the earliest stages of enterovirus infection as they occur in living cells. The study, was published in the <a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.1073/pnas.2601182123">PNAS journal</a>.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/CEITEC_Vedci_z_CEITEC_jako_prvni_zachytili_jak_enteroviry_spousteji_infekci_bunek_2_3601bf1df9.jpg" alt="CEITEC/Plevka Lab: CEITEC Scientists Are the First to Capture How Enteroviruses Initiate Infection: Reconstructions of E18 particles from infected cells. The particles are rainbow-colored based on the distance from the particle center. Scale 10 nm." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_CEITEC_Vedci_z_CEITEC_jako_prvni_zachytili_jak_enteroviry_spousteji_infekci_bunek_2_3601bf1df9.jpg 245w," sizes="100vw" width="1600" height="906"><blockquote><h4>Article</h4><h4><a target="_blank" rel="noopener noreferrer" href="https://www.pnas.org/doi/10.1073/pnas.2601182123">Particles of echovirus 18 open to release their genomes in vivo</a></h4>Liya Mukhamedova, David Buchta, Zuzana Trebichalská, Yevgen Levdansky, Jana Moravcová, David Potěšil, Zbyněk Zdráhal, Dominik Hřebík, Lucie Nepovímová, Torleif Tollefsrud Gjølberg, Jan Terje Andersen, Jiří Nováček, Tibor Füzik, and Pavel PlevkaProc. Natl. Acad. Sci. U.S.A., 2026, 123, e2601182123<div>&nbsp;</div><div><a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.1073/pnas.2601182123">https://doi.org/10.1073/pnas.2601182123</a></div><h6>licenced under <a target="_blank" rel="noopener noreferrer" href="https://creativecommons.org/licenses/by/4.0/">CC-BY 4.0</a></h6></blockquote><h4>Abstract</h4>Enteroviruses cause a broad spectrum of human diseases, ranging from mild respiratory or gastrointestinal infections to severe neurological disorders such as aseptic meningitis and encephalitis. Enterovirus cell entry involves receptor-mediated endocytosis followed by destabilizing rearrangements of the virus capsid that enable genome release. However, the mechanism of enterovirus genome release has not been visualized in infected cells. Here, we used cryoelectron tomography and microscopy to image echovirus 18 (E18) entry into host cells and its interaction with the neonatal Fc receptor (FcRn). 30 min postinfection, endosomes and cytoplasm contained empty capsids missing one or several pentamers of capsid proteins, providing evidence that in vivo E18 releases its genome through capsid opening. In vitro, FcRn binding induced the expulsion of pocket factors from hydrophobic pockets in VP1, priming the virus for uncoating. The cryoelectron microscopy reconstruction of genome-containing particles of E18 inside infected cells did not reveal pocket factors, indicating that receptor binding triggers the same priming process during infection. We did not detect activated particles in infected cells, suggesting that these intermediates are short-lived and rapidly release their genomes in vivo. Our results identify capsid opening as the in vivo mechanism of echovirus 18 genome release, providing structural evidence for a process previously only inferred from in vitro experiments.

CEITEC Scientists Are the First to Capture How Enteroviruses Initiate Infection 

Our Library never stops expanding. What are the most recent contributions to LabRulezICPMS Library in the week of 7th September 2026? Check out new documents from the field of spectroscopy/spectrometry and related techniques!<blockquote>👉 <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library">SEARCH THE LARGEST REPOSITORY OF DOCUMENTS ABOUT SPECTROSCOPY/SPECTROMETRY RELATED TECHNIQUES</a></blockquote><blockquote>👉 Need info about different analytical techniques? Peek into <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library">LabRulezLCMS</a> or <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library">LabRulezGCMS</a> libraries.</blockquote>This week we bring you application notes by Agilent Technologies, Metrohm and Shimadzu and brochure by Thermo Fisher Scientific!<h3>1. Agilent Technologies: <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/icpms/library?mainauthorItems=10&amp;search=9500">Agilent 9500 ICP‑QQQ</a> with m‑Lens for Ultratrace Analysis of High‑Purity Reagents</h3>Achieving low backgrounds under hot plasma conditions using ICP-QQQ preset methods&nbsp;<ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/pdf/an_m_lens_high_purity_reagents_9500_icp_qqq_5994_9062en_agilent_f0e65c4d9b.pdf">Full PDF for download</a>&nbsp;</li></ul>Controlling trace-metal contaminants is essential in both semiconductor reagent analysis and metal‑based materials characterization. High‑purity chemicals such as nitric acid (HNO3) and sulfuric acid (H2SO4), as well as high‑purity metals, require analytical workflows capable of achieving sub‑ppt detection limits (DLs) while maintaining excellent robustness and reproducibility. To meet these needs, the <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/icpms/library?mainauthorItems=10&amp;search=9500">Agilent 9500 Triple Quadrupole ICP‑MS (ICP‑QQQ)</a> equipped with a Dual‑Cell System (DCS)1 and the optional m‑lens ion optics provides a highly stable platform, enabling low backgrounds and reliable performance under hot plasma conditions.&nbsp;The m‑lens is engineered to suppress background signals for elements including easily ionized elements such as Na and K that typically show elevated background equivalent concentrations (BECs) under hot plasma conditions. The 9500 ICP-QQQ with m‑lens is suitable for the analysis of metal digests and other sample types that demand robust performance and low backgrounds.2However, its benefits also extend to low‑matrix, high‑purity reagents, supporting sub‑ppt impurity measurements of simpler matrices.3&nbsp;Agilent’s ICP‑QQQ portfolio allows users to select instruments based on desired DLs and operational objectives. For laboratories seeking the lowest possible DLs, the Agilent 8900 Semiconductor configuration ICP-QQQ equipped with an s‑lens provides exceptional sensitivity, making it suitable for laboratories operating at the extreme limits of ultratrace quantification. The 9500 ICP-QQQ with m‑lens provides robust, high sensitivity measurements, ideal for routine trace level applications. This model is appropriate for labs that may not require the lowest DLs for every element but still demand high‑quality, reproducible data.&nbsp;In this study, we evaluated the performance of the 9500 ICP‑QQQ using a method designed specifically for low‑matrix, high‑purity reagents. Using preset methods implemented in the instrument software for ultrapure water (UPW) and for H2SO4 —the UPW method is also applicable to diluted HNO3 and H2O2 — we analyzed 1% HNO3 and high purity H2SO4 separately. Sub-ppt DLs and low backgrounds were achieved for target analytes in both matrices. These results confirm that the 9500 ICP‑QQQ with m-lens can be used for ultratrace impurity analysis of semiconductor‑grade reagents, as well as demanding metal‑matrix applications.&nbsp;<h4>Experimental</h4><h5>Instrumentation&nbsp;</h5>The <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/icpms/library?mainauthorItems=10&amp;search=9500">Agilent 9500 ICP-QQQ</a> fitted with the optional m-lens and the Agilent I-AS autosampler were fully controlled using Agilent OpenLab ICP-MS software version 1.1. Designed for ultratrace metal analysis, the sample introduction system comprised a MicroFlow PFA nebulizer with I-AS probe (operated in self-aspiration mode), a temperature-controlled quartz spray chamber, and a quartz torch with a 2.5 mm inner diameter (id) injector. A platinum-tipped sampler cone with copper base and a platinum-tipped skimmer cone with nickel base for m-lens were used.&nbsp;The 9500 ICP‑QQQ was operated using five tune modes: no gas, Advanced Helium Mode (AHM), O2 , NH3 , and H2 . For the H2 SO4 samples, additional specialized tunes were prepared for the determination of platinum (Pt) and zinc (Zn) to ensure optimal performance (Table 1). The use of reaction and collision gases enabled effective removal of spectral interferences originating from argon plasma species as well as matrix‑related polyatomic ions. The makeup gas flow rate and the Omega lens voltage parameters were automatically optimized by the preset methods for m-lens, resulting in a stable CeO/Ce ratio that was maintained between approximately 1 and 3%.<h4>Conclusion&nbsp;</h4>This study evaluated the Agilent 9500 ICP‑QQQ with m‑lens for ultratrace analysis of high‑purity reagents using preset methods for 1% HNO3 and 9.8% H2 SO4 . Sub‑ or singlefigure ppt detection limits and low background equivalent concentrations were achieved for all elements, demonstrating that ultratrace measurements can be easily performed under hot‑plasma conditions. The Dual‑Cell System enabled effective removal of matrix‑related interferences, with Advanced Helium Mode providing an effective approach for the measurement of challenging elements such as Zn in H2 SO4 . The results show that the 9500 ICP‑QQQ with intuitive preset methods can deliver sensitive, low-background data, offering an accessible entry point for laboratories that are new to ultratrace analysis.<h3>2. Metrohm: Rapid quality control of fruits and vegetables using NIR spectroscopy</h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/pdf/an_nir_141_download_e1bab41aee.pdf">Full PDF for download</a></li></ul>Near-infrared (NIR) spectroscopy has emerged as a powerful, nondestructive analytical technique for quality control in the fruit and vegetable processing industry. This Application Note presents the use of NIR spectroscopy for the rapid monitoring of firmness in apples and °Brix in peaches and crushed tomatoes. These are critical parameters to verify the quality and freshness of various fruits and vegetables. Traditionally measured using destructive methods like penetrometry and refractometry, these fresh produce quality control attributes are critical indicators of ripeness, sweetness, and overall consumer acceptability.<h4>EXPERIMENTAL EQUIPMENT</h4>All samples were tested with a <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/icpms/library?mainauthorItems=220&amp;search=NIR">Metrohm near-infrared (NIR) spectrometer.</a> The measurements were done in reflection mode using either a large sample cup or direct measurement (i.e., no holder). Metrohm software was used for all data acquisition and quantification model development.<h4>CONCLUSION</h4>This Application Note shows that NIR spectroscopy can easily measure firmness in apples, as well as °Brix in peaches and crushed tomatoes. When compared to traditional lab methods (Table 1), NIRS provides a faster, simpler, and nondestructive alternative with excellent accuracy and consistency. All measurements proved to be consistent and fast, helping producers to monitor their fresh fruits and vegetables and deliver high-quality products to consumers.<h3>3. Shimadzu: Evaluation of Surface Carbon on Lithium-Ion Battery Cathode Active Materials Using a TOC Analyzer and Infrared/Raman Microscope</h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/pdf/an_01_01122_en_b3b0f25211.pdf">Full PDF for download</a></li></ul><h5>User benefits</h5><ul><li>The TOC solid sample measurement system enables quantitative evaluation of carbon coatings on cathode active material surfaces.</li><li>The AIRsight infrared/Raman microscope enables evaluation of the carbon layer structure.</li><li>Carbon content and structure can be evaluated using a small amount of sample.</li></ul>The cathode active materials used in lithium-ion batteries (LiBs) for electric vehicles (EVs) are broadly classified into two categories depending on their application: nickel-based materials (NCM/NCA/NCMA) and phosphate-based materials (LFP: LiFePO4, LMFP: LiFexMn1-xPO4). Nickel-based materials are characterized by high energy density as well as excellent low-temperature and high-power performance, making them indispensable for longrange driving and high-performance vehicle segments. In contrast, phosphate-based materials offer superior safety, long cycle life, and cost advantages, and their use is expanding primarily in standard-range and mass-market segments.Because LFP and LMFP compounds are intrinsically low in electronic conductivity, a carbon coating on the surface of the active material is essential to compensate for that limitation and improve performance. Accordingly, quantitative control of carbon content is of great importance. For that type of carbon analysis, the TOC solid sample measurement system (Fig. 1), which combines a TOC-L total organic carbon analyzer with an SSM-5000A solid sample combustion unit, is effective.&nbsp;Furthermore, the conductivity of the surface carbon layer is closely related to the degree of graphitization and defect structure of the carbon, making structural evaluation of the carbon layer equally important. The <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/icpms/library?mainauthorItems=1&amp;search=AIRsight">AIRsight infrared/Raman microscope</a> (Fig. 2) enablessuch structural evaluation.&nbsp;This Application News presents examples of evaluating carbon on the surface of LMFP cathode active materials, with carbon quantitation using a <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/icpms/library?mainauthorItems=1&amp;search=TOC-L">TOC-L </a>+ <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/icpms/library?mainauthorItems=1&amp;search=SSM-5000A">SSM-5000A system</a> and carbon layer structure evaluation using the AIRsight infrared/Raman microscope.<h4>Conclusion&nbsp;</h4>Quantitative analysis of the carbon coating on the LMFP surface was performed using the TOC solid sample measurement system (TOC-L + SSM-5000A), and structural evaluation of the carbon layer was conducted using the AIRsight microscope. In addition, Raman analysis of the LMFP residue after TC analysis was carried out to verify the validity of the carbon quantitation results. The TOC solid sample measurement system (TOC-L + SSM-5000A) is capable of not only TC analysis in solid samples, but also of IC and TOC analysis. Furthermore, by simply changing the software settings, carbon analysis of liquid samples (TOC, TC, and IC) can also be performed using the TOC-L main unit. This system can also be applied to carbon analysis of water-extractable TOC in black mass, lithium extraction solutions, and lithium carbonate, all of which are relevant materialsin lithium-ion battery recycling. The AIRsight is capable of both Raman and infrared measurements. Therefore, in addition to the Raman measurements introduced here, it can be used, with a single microscope system, to evaluate degradation caused by charge and discharge cycles in various battery components, such as negative electrode materials and separators.<h3>4. Thermo Fisher Scientific: <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/all/products/2002">Thermo Scientific GS Omni</a> Light Element Analysis in Slurry Process Streams</h3><ul><li>Brochures and specifications</li><li><a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/pdf/CAD_GS_Omni_Light_Element_Analyzer_bf50abdb7e.pdf">Full PDF for download</a></li></ul>The <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/all/products/2002">Thermo Scientific™ GS Omni analyzer</a> provides accurate, real-time elemental analysis of multiple slurry streams for both light and heavy elements. Using the Prompt Gamma Neutron Activation Analysis (PGNAA) technology, the GS Omni analyzer has a distinct advantage over analyzers using X-ray fluorescence (XRF) and Laser induced breakdown spectroscopy (LIBS) by being able to directly measure elements lower than calcium on the periodic table and particle sizes up to 5mm.<h4>Benefits&nbsp;</h4>The Thermo Scientific GS (Gamma Slurry) Omni analyzer is the latest development of a proven, robust, analyzer that provides direct simultaneous analysis of multiple elements in slurry beneficiation plants.&nbsp;The analyzer is available in configurations of 2 to 8 streams. The optimum number of streams is usually dependent on the stream concentrations, elements of interest, required cycle analysis time, plant layout and process control considerations. This elemental analyzer will enable improvements in product quality, recovery and lower production costs.&nbsp;<h4>Applications&nbsp;</h4>The Thermo Scientific GS Omni analyzer is a powerful measurement tool in the following applications:&nbsp;<ul><li>Slurry beneficiation / Light element analysis&nbsp;</li><li>Product quality / Penalty costs&nbsp;</li><li>Tailings management&nbsp;</li></ul>Slurries include:&nbsp;<ul><li>Iron ore&nbsp;</li><li>Sulphur&nbsp;</li><li>Phosphates&nbsp;</li><li>Copper&nbsp;</li><li>Calcium carbonate&nbsp;</li><li>Magnesium&nbsp;</li><li>Industrial Minerals</li></ul>

News from LabRulezICPMS Library - Week 37, 2026

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Analytical Services for Building Materials (Watrex Laboratory)

Comprehensive analysis of building materials by ion chromatography and gravimetry – salts, moisture, lime, gypsum, density, and absorption testing by Watrex Laboratory.

<h5>WI08101 – Determination of Water-Soluble Salts in Building Materials</h5><ul><li>Determination of chlorides, nitrates, and sulfates in aqueous extract using ion chromatography. Requires approx. 1 g of a homogeneous sample.</li><li>Price: 600 CZK excl. VAT</li></ul><h5>WI08102 – Determination of Moisture in Building Materials</h5><ul><li>Gravimetric method after drying the sample to constant weight. Moisture content is expressed in mass %. Requires at least 10 g of sample in sealed packaging.</li><li>Price: 300 CZK excl. VAT</li></ul><h5>WI08103 – Determination of Lime Content in Lime Mortars</h5><ul><li>After acid digestion, Ca and Mg content is determined to calculate CaCO₃ and MgCO₃. Sand content determined gravimetrically. Not suitable for cement mortars. Requires approx. 5 g of sample.</li><li>Price: 1,275 CZK excl. VAT</li></ul><h5>WI08104 – Semi-Quantitative Determination of Gypsum in Building Materials</h5><ul><li>Based on solubility differences of gypsum and alkaline sulfates. Requires approx. 11 g of sample.</li><li>Price: 1,100 CZK excl. VAT</li></ul><h5>WI08105 – Determination of Bulk Density of Building Materials</h5><ul><li>Performed using quartz sand displacement. Requires 30–50 cm³ of sample in pieces 2–4 cm.</li><li>Price: 440 CZK excl. VAT</li></ul><h5>WI08109 – Determination of Hygroscopic Moisture in Building Materials</h5><ul><li>Gravimetric method after equilibrium at 100% RH and drying at 105 °C for 2 hours. Requires approx. 10 g of sample.</li><li>Price: 440 CZK excl. VAT</li></ul><h5>WI08114 – Determination of Water Absorption of Building Materials</h5><ul><li>Gravimetric method from weight difference between dried and water-saturated sample. Bulk density determined simultaneously. Requires 30–50 cm³ of sample in pieces 2–4 cm.</li><li>Price: 4,495 CZK excl. VAT</li></ul><blockquote>10% discount when submitting 3 or more samples at once.</blockquote><blockquote><h3>Services – Laboratory</h3>The Watrex Analytical Laboratory will be happy to perform any of our standard analyses, custom analyses, or assist you with method development.We specialize primarily in liquid chromatography techniques and are ready to meet a wide range of requirements—from method development and optimization, through validation and verification of external methods, to training and troubleshooting.Our laboratory also manufactures and packs its own chromatographic columns and guard columns for basic HPLC modes (reversed phase, normal phase, ion chromatography, and ion exclusion chromatography).<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Watrex_Analyticka_laborator_fc8862fba5.jpg" alt="Watrex: Analytical Laboratory" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Watrex_Analyticka_laborator_fc8862fba5.jpg 245w," sizes="100vw" width="1569" height="637"></blockquote>

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CEITEC Scientists Are the First to Capture How Enteroviruses Initiate Infection

News from LabRulezICPMS Library - Week 37, 2026

Size distribution and elemental analysis of fine particles from Li-ion battery cell fire