Post-translational modifications (PTMs) are where so much of biology’s complexity lives, but they are also some of the hardest molecular features to analyze with confidence. Phosphorylation, asymmetric dimethylarginine (ADMA), and O-GlcNAcylation (O-GlcNAc) often occur at low abundance, can be highly labile, and frequently require precise site localization to understand their biological meaning. This<a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/tn_004377_ov_phosphorylation_ptm_etd_excedion_pro_tn004377_na_en_71f681655f.pdf"> technical note </a>shows how the <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/1958">Thermo Scientific Orbitrap Excedion Pro Hybrid Mass Spectrometer</a> helps address those challenges by combining fast, sensitive performance with complementary <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/article/7217">HCD and EThcD fragmentation</a> workflows.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Thermo_Fisher_Scientific_Phosphorylation_ADMA_and_O_Glc_N_Ac_Analysis_on_the_Orbitrap_Excedion_Pro_Mass_Spectrometer_d24a5de98e.jpg" alt="Thermo Fisher Scientific: Phosphorylation, ADMA, and O-GlcNAc Analysis on the Orbitrap Excedion Pro Mass Spectrometer" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Thermo_Fisher_Scientific_Phosphorylation_ADMA_and_O_Glc_N_Ac_Analysis_on_the_Orbitrap_Excedion_Pro_Mass_Spectrometer_d24a5de98e.jpg 245w," sizes="100vw" width="1024" height="512">Using enriched PTM samples and automated data-dependent acquisition, the study demonstrates that the Orbitrap Excedion Pro MS can deliver both depth and confidence across multiple PTM classes. For phosphorylation analysis, the platform identified 5,892 unique phosphosites from IMAC-enriched samples and 2,941 unique phosphotyrosine sites after phosphotyrosine enrichment, highlighting strong performance for both broad and highly targeted signaling studies. Just as importantly, the data show that HCD and EThcD provide complementary value, with each fragmentation method contributing unique site identifications and helping resolve ambiguous assignments.The note also highlights the value of EThcD for more analytically demanding PTMs. In ADMA-enriched samples, EThcD delivered more ADMA peptide-spectrum matches and more unique modified peptides than HCD, supporting improved confidence in site characterization. For O-glycopeptides, the Orbitrap Excedion Pro MS uses an intelligent HCD-product-dependent-EThcD strategy that triggers EThcD only when oxonium ions are detected, improving productivity while preserving the fragmentation detail needed for confident glycosite localization.Overall, this technical note shows how Orbitrap Excedion Pro MS enables researchers to go deeper into PTM biology with greater sensitivity, better site confidence, and smarter acquisition. For scientists studying signaling, regulation, and disease mechanisms, it presents a powerful approach for expanding PTM coverage without compromising analytical rigor.<blockquote><h5><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/tn_004377_ov_phosphorylation_ptm_etd_excedion_pro_tn004377_na_en_71f681655f.pdf">Download the technical note "Advancing phosphorylation, ADMA, and O-GlcNAc PTM analysis with HCD and EThcD on the Orbitrap Excedion Pro mass spectrometer"</a></h5></blockquote>Visit us on&nbsp;<a target="_blank" rel="noopener noreferrer" href="https://www.linkedin.com/showcase/72003132/admin/dashboard/">LinkedIn:</a>&nbsp;#PTM #OrbitrapExcedionPro #glycosylation #phosphorylation

Phosphorylation, ADMA, and O-GlcNAc Analysis on the Orbitrap Excedion Pro Mass Spectrometer

<h3>Refractive Index (RI) Detection in HPLC – Making Invisible Compounds Visible</h3>When HPLC detectors are discussed, UV-Vis absorbance detection is often the first technique that comes to mind. Its popularity is easy to understand: it is sensitive, selective, and suitable for a wide range of compounds. But what happens when the analyte does not absorb ultraviolet or visible light?This is where the <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/all/products/2429">Refractive Index Detector (RID)</a> becomes particularly useful. Reliable, versatile, and often described as a “universal detector” for HPLC, RI detection can reveal compounds that remain invisible to many optical detectors. For substances such as sugars, polymers, lipids, or alcohols, it is often an important analytical option.Let’s look at how RI detection works, where it performs best, what its main limitations are, and how to achieve stable, reproducible results.<h4>How RI Detection Works</h4>When light passes from one medium into another, its path changes direction, or refracts, depending on the phase velocity and angle of incidence. This phenomenon is described by Snell’s law, with the extent of refraction determined by the refractive index (RI) of the medium (Figure 1).<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Figure_1_Refraction_of_light_at_the_interface_between_two_media_with_different_refractive_indices_baa4aad28c.webp" alt="KNAUER: Figure 1: Refraction of light at the interface between two media with different refractive indices, where n₁ &gt; n₂. Since the velocity is lower in the second medium (v₂ &lt; v₁), the angle of refraction α₂ is less than the angle of incidence α₁." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Figure_1_Refraction_of_light_at_the_interface_between_two_media_with_different_refractive_indices_baa4aad28c.webp 238w," sizes="100vw" width="1024" height="670">In HPLC, an RI detector monitors small changes in the refractive index of the mobile phase as compounds elute from the column. Because each substance has its own refractive index, even relatively small changes in the composition of the column effluent can generate a measurable response.Modern RI detectors generally use a differential optical design (Figure 2). Two optical paths are continuously compared: one passes through a reference cell containing pure mobile phase, while the other passes through a sample cell containing the column effluent, i.e. mobile phase plus analyte.A light source, commonly an LED or tungsten lamp, illuminates both cells. Changes in refractive index alter the path of the light, and a photodiode detects the resulting deviation.When only mobile phase is present, the two optical paths are effectively identical and no significant detector response is produced. As an analyte enters the sample cell, however, the refractive index changes. The light beam is slightly deflected, creating an optical imbalance and consequently a change in light intensity.The detector converts this change into an electrical signal, which appears as a chromatographic peak. Because the response is related to analyte concentration, RI detection can also be used for quantitative analysis.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Figure_2_Schematic_of_a_differential_RI_detector_with_dual_flow_cell_6299f55b17.webp" alt="KNAUER: Figure 2: Schematic of a differential RI detector with dual flow cell. The sample cell carries column effluent; the reference cell contains pure mobile phase. A light beam passes through both and forms a slit image on a photodiode. Any analyte-induced change in refractive index alters the beam’s path, shifting the image on the photodiode and generating a signal peak." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Figure_2_Schematic_of_a_differential_RI_detector_with_dual_flow_cell_6299f55b17.webp 245w," sizes="100vw" width="1024" height="524">For reliable measurements, the reference cell must always contain the same mobile phase as the sample cell, but without analyte. It therefore needs to be refreshed regularly with clean mobile phase, commonly using a switching valve and/or T-piece (Figure 3).<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Figure_3_Flow_path_in_the_AZURA_RID_2_1_L_during_analysis_left_and_flushing_right_e6bc30acef.webp" alt="KNAUER: Figure 3: Flow path in the AZURA® RID 2.1L during analysis (left) and flushing (right). During analysis, solvent flows from the IN port through the heat exchanger and sample cell, then continues through the T piece and flush valve to the OUT port. During flushing, the valve redirects the flow through the T piece so the solvent passes a second heat exchanger and reference cell before exiting via the OUT port." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Figure_3_Flow_path_in_the_AZURA_RID_2_1_L_during_analysis_left_and_flushing_right_e6bc30acef.webp 245w," sizes="100vw" width="1024" height="410">It is important to remember that refractive index depends on both light wavelength and medium density. The wavelength is fixed by the optical design of the detector, but density—and therefore refractive index—changes with temperature, pressure, and composition.For this reason, RI detection is particularly sensitive to changes in operating conditions. Stable measurements depend heavily on maintaining a tightly controlled analytical environment.<h4>Why Choose RI Detection?</h4>RI detectors become especially valuable when other detector types cannot provide a useful response. They may be less sophisticated than some modern detection technologies, but several characteristics make them indispensable for particular applications.<h5>Broad Applicability</h5>An RID can detect virtually any compound that produces a change in the refractive index of the mobile phase. No UV-absorbing chromophore is required.Because almost every dissolved substance changes refractive index to some degree, RI detection is commonly regarded as a universal detection technique. Typical analytes include sugars, alcohols, lipids, fatty acids, and polymers.<h5>Non-Destructive Detection</h5>RI measurement does not destroy the analyte. This makes it useful in workflows where the separated compound needs to be collected or analyzed further, including preparative chromatography.KNAUER’s <a target="_blank" rel="noopener noreferrer" href="https://store.knauer.net/shop/add38-azura-r-rid-2-1l-highflow-preparative-refractive-index-detector-62927?category=75">AZURA® RID 2.1L for preparative applications</a>, for example, supports flow rates up to 100 mL/min.<h5>Simple and Reliable Operation</h5>RI detectors are suitable for aqueous and many organic mobile phases as long as the solvent composition remains constant.Under stable isocratic conditions, they are relatively straightforward to use, robust, and require comparatively little maintenance.<h5>Direct Detection Without Derivatization</h5>Analytes do not need to be derivatized or labelled before RI detection. If a compound is soluble in the mobile phase and produces a sufficient difference in refractive index, it can be detected directly.This simplifies sample preparation and reduces additional handling steps that could introduce variability or error.These characteristics make RI detection particularly attractive for routine applications such as lactose determination in milk or polymer purity testing.<h5>Limitations of RI Detection</h5>Universal detection comes with several practical compromises. RI detectors require highly stable conditions and can be considerably more sensitive to environmental and system changes than other common HPLC detectors.<h5>High Temperature Sensitivity</h5>Refractive index is strongly influenced by temperature. For aqueous solvents, the change in refractive index with temperature is approximately dn/dT ≈ 10⁻⁴/°C.Even small temperature fluctuations can therefore produce baseline drift that may be larger than the analytical signal itself.Modern RI detectors use thermostated compartments and heat exchangers to stabilize the temperature of the flow cell. This improves accuracy and reproducibility, although the heat exchangers introduce additional system volume that can contribute to peak broadening compared with UV detection.<h5>Limited Compatibility With Gradient Elution</h5>RI detection is essentially restricted to isocratic chromatography.Changing the composition of the mobile phase during a gradient produces a much larger change in refractive index than the analyte itself. The resulting baseline shift can easily overwhelm chromatographic peaks.A stable RI baseline therefore requires the sample and reference cells to contain the same mobile-phase composition throughout the analysis.<h5>Lower Sensitivity</h5>Compared with UV detection, RI detection is generally about one to two orders of magnitude less sensitive.Typical detection limits are in the µg–mg/mL range, making RID less suitable for trace-level analysis or impurity profiling.<h5>Limited Pressure Tolerance</h5>RI flow cells can tolerate only moderate backpressure. When several detectors are connected in series, the RI detector should therefore normally be positioned last.<h5>Longer Equilibration</h5>RID systems require time to reach thermal and optical stability. Warm-up and equilibration can take hours before a sufficiently stable baseline is obtained.<h5>Sensitivity to Baseline Disturbances</h5>Because the detector responds to any change in refractive index, many factors can affect the baseline.Temperature fluctuations, unstable flow or pressure, pump pulsation, air bubbles, inadequate solvent mixing, and impurities in the mobile phase can all lead to noise, drift, or false signals.Clean operation and stable system conditions are therefore essential.<h4>How to Get the Best Performance From an RI Detector</h4>Successful RI detection can largely be summarized in one word: stability.Small variations in temperature, flow, solvent composition, or pressure can quickly become visible in the chromatographic baseline. Careful system preparation and handling can therefore make a major difference.<h5>Maintain a Stable Temperature</h5>Thermal equilibration should be one of the first priorities.Allow the detector, column, and mobile phase to equilibrate fully before beginning analysis, ideally for at least 60 minutes. A column oven can help maintain stable conditions, and the column and detector should be operated at the same temperature whenever possible.Environmental influences such as direct sunlight, air currents, or day-to-night laboratory temperature fluctuations should also be minimized.<h5>Use Isocratic Methods</h5>Keep the mobile-phase composition constant throughout the run.If the separation requires gradient elution, an RI detector is generally not the appropriate choice.<h5>Degas the Mobile Phase and Keep the System Clean</h5>Use well-degassed, particle-free mobile phases and make sure the LC system is properly primed.An in-line degasser can help prevent bubble formation. Tubing, solvent reservoirs, and the entire flow path should also be kept clean because even small bubbles or contaminants can generate spikes, noise, or other baseline disturbances.<h5>Match the Sample Solvent Carefully</h5>Whenever possible, prepare samples directly in the mobile phase or in a solvent with very similar composition.Large differences between the injection solvent and mobile phase can produce strong refractive-index disturbances around the void volume.Filtering samples also helps reduce the risk of blockages and protects the detector flow cell.<h5>Keep Flow and Pressure Stable</h5>Maintain a constant flow rate and avoid abrupt pressure changes, excessive pump pulsation, or leaks.A restriction capillary or back-pressure regulator positioned after the flow cell may help stabilize pressure, although these measures cannot compensate for noise caused by a poorly performing pump.<h5>Maintenance and Practical Considerations</h5>Flush the reference cell regularly with fresh mobile phase. The mobile phase itself should also be replaced periodically to reduce microbial growth or compositional changes caused by evaporation.When changing solvent systems, flush the instrument with mutually miscible solvents and allow sufficient time for the new system to equilibrate fully.Where appropriate, mobile-phase recycling or a low-flow standby mode can help reduce solvent consumption and shorten restart times between analytical sequences.<blockquote>👉 Pro Tip: Keep an eye on the baseline. A stable baseline is one of the best signs that the RID has equilibrated properly. Negative peaks are not necessarily an error—they simply indicate that the analyte has a lower refractive index than the mobile phase.</blockquote><h5>The Bottom Line</h5>With careful control of temperature, mobile-phase composition, pressure, and cleanliness, an RI detector can provide stable baselines and consistent quantitative data.Keep the system clean, maintain constant operating conditions, and allow sufficient equilibration time, and even this demanding HPLC “diva” can deliver highly reliable results.<h4>Typical Applications: Where RI Detection Performs Best</h4>RI detection is particularly useful for substances that do not absorb UV light strongly and therefore cannot be detected effectively using conventional UV/VIS detectors.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_AI_Figure_4_Common_uses_of_RI_detection_in_HPLC_d84d8458dc.webp" alt="KNAUER / AI: Figure 4: Common uses of RI detection in HPLC" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_AI_Figure_4_Common_uses_of_RI_detection_in_HPLC_d84d8458dc.webp 245w," sizes="100vw" width="1024" height="433">Typical analytes include sugars, alcohols, fatty acids, polymers, lipids, and other small organic molecules without strong chromophores.<h5>Some common application areas include:</h5><ul><li>Carbohydrate and sugar analysis, including determination of glucose, fructose, sucrose, or lactose in food and beverages. HPLC-RI has been used for <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/pdf/VFD_0195_sec_for_fingerprint_analysis_of_gummy_candies_ce5349cd95.pdf">product quality control of gummy candies</a>, with further discussion available in this <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/all/article/7186">related blog post</a>.</li><li>KNAUER’s AZURA® RID 2.1L has also been used for the <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/pdf/VFD_0194_d497a35278.pdf">simultaneous determination of sugars and organic acids in wine</a>, an application explored further in the article <a target="_blank" rel="noopener noreferrer" href="https://www.knauer.net/blog/blog-9/the-hidden-science-in-your-glass-147">“The hidden science in your glass”</a>.</li><li>Polymer and macromolecule characterization in GPC/SEC applications, for example when determining molecular-weight distributions. Examples include <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/pdf/4czsecf32d70a6d2yugpojtljg8rvp4vd4ur_05660bfad3.pdf">optimization of molecular-weight determination with the KNAUER AZURA® GPC/SEC system</a> and <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/pdf/qpwsk0igeqca8b5bqunbjjqnwum09tucb83s_cc4dbbcec9.pdf">analysis of mucin proteins using an AZURA® SEC System</a>.</li><li>Bioprocessing, including monitoring fermentation products such as <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/pdf/VBS_0079_Characterization_of_fructans_in_fermentation_products_with_sec_bc8f294f0e.pdf">fructans</a>.</li><li>Pharmaceutical applications, for example analysis of excipients such as sugars and polyols, as well as identity and purity testing of APIs. Dextranes, which are used as carrier materials in pharmaceuticals and as thickening or moisturizing agents in cosmetics, can be <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/pdf/h2oikq51kfvn6ebxij6hs88pxupstfgdqfyd_3e4f29d933.pdf">characterized by SEC</a>, as their properties depend strongly on molecular-weight distribution.</li><li>Lipid and surfactant analysis for formulation development and quality control.</li><li>Environmental analysis, including determination of selected organic and inorganic impurities in water samples.</li></ul>Overall, RI detection works best for analytes that are soluble, stable in solution, and compatible with straightforward isocratic separation conditions.It is not the preferred solution for trace analysis, gradient chromatography, or workflows requiring direct MS coupling. Nevertheless, it remains a practical and dependable option for compounds that are difficult or impossible to monitor using UV or fluorescence detection.<h4>Final Thoughts: A Detector That Still Deserves Attention</h4>As analytical laboratories adopt increasingly sophisticated detection technologies, refractive index detection can appear relatively simple. Yet for many applications, that simplicity is exactly its strength.For analytes such as sugars, alcohols, polymers, and other compounds without strong UV absorption, RID offers a direct, reliable, and non-destructive method of detection.Its greatest challenges are its sensitivity to temperature and its incompatibility with gradient elution. Under carefully controlled isocratic conditions, however, RI detection remains a dependable workhorse for routine HPLC and GPC/SEC applications.<blockquote>Pro tip: If your analyte seems invisible to conventional optical detection, a change of perspective may be all that is needed. RI detection could make it visible.</blockquote>In the next article in the “Seeing is Believing – Detection Made Easy” series, we will focus on Fluorescence Detection (FLD), a highly selective and sensitive technique for compounds that fluoresce naturally or can be derivatized to do so.

Seeing is Believing – Detection Made Easy Part 4: Refractive Index Detector

News from LabRulezLCMS Library - Week 36, 2026

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Waters XBridge BEH Protein C4 HPLC Columns

Waters XBridge Protein BEH C4 column is QC tested and optimized to separate proteins based on size, hydrophobicity and isoelectric point. 

The XBridge Protein BEH C4 column is QC tested and optimized to separate proteins based on size, hydrophobicity and isoelectric point. If you compare to traditional C18 phases, the C4 ligand is less retentive and will minimize protein carryover, increase protein recovery, and improve peak capacity.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Waters_X_Bridge_BEH_Protein_C4_HPLC_Columns_0aa4f56918.jpeg" alt="Waters: XBridge BEH Protein C4 HPLC Columns" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Waters_X_Bridge_BEH_Protein_C4_HPLC_Columns_0aa4f56918.jpeg 234w," sizes="100vw" width="660" height="440"><h4>Specifications</h4><ul><li>Chemistry: C4</li><li>Separation Mode: Reversed Phase</li><li>Particle Substrate: Hybrid</li><li>pH Range Min: 2 pH</li><li>pH Range Max: 10 pH</li><li>Maximum Pressure: 6000 psi (415 Bar)</li><li>Endcapped: No</li><li>Silanol Activity: Low</li><li>Molecular Weight Range Max: 150000</li><li>Particle Shape: Spherical</li><li>System: HPLC</li><li>Particle Technology: BEH</li><li>USP Classification: L26</li><li>Carbon Load: 8 %</li></ul><h3>XBridge Columns</h3><h4>Particle stability and performance for methods development</h4>Withstanding extreme operating conditions like high pH and high temperatures is essential for methods development. XBridge HPLC and UHPLC Columns utilize Ethylene Bridged Hybrid (BEH) Particle Technology and are built to withstand high pH, high temperatures, and other extreme operating conditions like volatile eluents, for a wide range of small molecule and biomolecule LC-MS analysis.XBridge HPLC and UHPLC Columns are available in a broad range of sorbent particles and sizes: XBridge eXtended Perfomance (XP) 2.5 µm Columns for rapid analytical UHPLC separations; 3.5 and 5 µm HPLC columns for reliable analytical method development; and 5 and 10 µm optimum bed density (OBD) preparative columns for purification chromatography.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Waters_X_Bridge_Columns_b0b55de501/Waters-XBridge-Columns.jpg" alt="Waters: XBridge Columns" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Waters_X_Bridge_Columns_b0b55de501/thumbnail_Waters-XBridge-Columns.jpg 203w," sizes="100vw" width="900" height="691">

Waters Symmetry C4 HPLC Columns

With Waters Symmetry C4 Column, you get the sharpest peaks for biomolecules and more peak capacity for complex tryptic maps. 

Primarily supports legacy methods. Symmetry columns give you confidence in the long-term compliance of your HPLC methods. No need to compromise on peak shape, selectivity, column-to-column and batch-to-batch reproducibility, or other critical performance characteristics. Available in a variety of particle sizes, chemistries and dimensions.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Waters_Atlantis_d_C18_HPLC_Columns_d7a741df9f.jpg" alt="Waters: Symmetry C4 HPLC Columns" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Waters_Atlantis_d_C18_HPLC_Columns_d7a741df9f.jpg 234w," sizes="100vw" width="660" height="440"><h4>Specifications</h4><ul><li>Chemistry: C4</li><li>Separation Mode: Reversed Phase</li><li>Particle Substrate: Silica</li><li>pH Range Min: 2 pH</li><li>pH Range Max: 8 pH</li><li>Maximum Pressure: 6000 psi (415 Bar)</li><li>Endcapped: Yes</li><li>Silanol Activity: Low</li><li>Particle Shape: Spherical</li><li>Pore Size: 300 Å</li><li>System: HPLC</li><li>USP Classification: L26</li><li>Carbon Load: 2.8 %</li><li>Application: Protein</li></ul><h3>Symmetry HPLC Columns</h3><h4>Silica-based columns that exceed HPLC column performance expectations</h4>Reproducible HPLC columns are essential when developing analytical methods for pharmaceutical and biopharmaceutical products. Achieving the same chromatographic results over the lifetime of a new drug product is critical, and no other silica-based LC column brand can match the column-to-column and batch-to-batch reproducibility of the Symmetry family.Available in column and guard formats, Symmetry Columns are manufactured using high purity silica and tightly controlled manufacturing processes to ensure that you receive a column that exceeds the standards for HPLC column performance.<h4>Overview</h4><ul><li>Deliver maximum reproducibility batch-to-batch and column-to-column</li><li>Provide superior peak shape</li><li>Achieve high recoveries of peptides and proteins</li><li>Manufactured using high purity silica and tightly controlled manufacturing processes</li><li>Recommended Use: For rugged and reproducible HPLC column performance.</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Waters_Symmetry_Columns_a2367d8095/Waters-Symmetry-Columns.jpg" alt="Waters: Symmetry Columns" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Waters_Symmetry_Columns_a2367d8095/thumbnail_Waters-Symmetry-Columns.jpg 223w," sizes="100vw" width="700" height="490">

Waters ACQUITY UPLC Protein BEH C4 Column

The Waters ACQUITY UPLC Protein BEH C4 column is QC tested and optimized to separate proteins based on size, hydrophobicity and isoelectric point. 

The ACQUITY UPLC Protein BEH C4 column is QC tested and optimized to separate proteins based on size, hydrophobicity and isoelectric point. If you compare to traditional C18 phases, the C4 ligand is less retentive and will minimize protein carryover, increase protein recovery, and improve peak capacity.<h5>Specifications</h5><ul><li>Chemistry: C4</li><li>Separation Mode: Reversed Phase</li><li>Particle Substrate: Hybrid</li><li>pH Range Min: 2 pH</li><li>pH Range Max: 10 pH</li><li>Endcapped: No</li><li>Silanol Activity: Low</li><li>Particle Shape: Spherical</li><li>Pore Size: 300 Å</li><li>System: UHPLC, UPLC</li><li>Particle Technology: BEH</li><li>USP Classification: L26</li><li>Carbon Load: 8 %</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Waters_ACQUITY_UPLC_BEH_C8_Column_9c78ca994d.jpg" alt="Waters: Kolona ACQUITY UPLC BEH C8" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Waters_ACQUITY_UPLC_BEH_C8_Column_9c78ca994d.jpg 234w," sizes="100vw" width="660" height="440"><h3>ACQUITY UPLC Columns</h3><h5>Increase speed, sensitivity, and resolution, without compromising data integrity</h5>Increasing sample throughput, achieving unmatched resolution, and improving analyte sensitivity are priorities for your separation goals. With Waters ACQUITY UPLC Columns, you can meet all your method requirements and substantially reduce your analysis time and cost-per-sample.Waters ACQUITY UPLC Columns’ sub-2-µm particle chemistries enable chromatographers to harness the separation efficiency improvements at increased flow rates of ultra-performance liquid chromatography (UPLC) technology, thereby improving analyte resolution and sensitivity as well as business productivity and profitability. &nbsp;<h4>Overview</h4><ul><li>Best-in-class column efficiency for superior separation speed, sensitivity, and resolution</li><li>8 UPLC particles of various substrate technologies, including Ethylene Bridged Hybrid (BEH), High Strength Silica (HSS), and Charged Surface Hybrid (CSH)</li><li>22 stationary phases, including C18, Phenyl-Hexyl, C8, Embedded-Polar, C4, HILIC, Amide, Diol, Cyano, and PFP</li><li>7 application-specific UPLC Column chemistries for SEC, proteins, peptides, oligonucleotides, glycan, and amino acid analysis</li><li>More than 50 different column dimensions and configurations, with internal column diameters ranging from 1.0–4.6 mm and column lengths ranging from 30–300 mm</li><li>Prolonged column lifetimes with optional VanGuard Cartridges specifically designed using ACQUITY stationary phases</li><li>Recommended Use: For improved speed, sensitivity, and resolution in methods development.</li></ul><h4>Particle technology</h4><h5>BEH - Ethylene Bridged Hybrid Particle Technology</h5>ACQUITY UPLC BEH 1.7 µm fully porous columns provide superior analyte peak shape, efficiency, and chemical stability to any separation. ACQUITY UPLC BEH Columns are available in both reversed-phase and HILIC separation modes, with chemistries that provide selectivities for a wide range of compounds. With the ruggedness to operate at extreme pH conditions, ACQUITY UPLC BEH Columns enable the separation scientist to use a wide pH range to influence retention, selectivity, and sensitivity for ionizable compounds.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Waters_BEH_technology_c07876b8a3.jpg" alt="Waters: BEH particle technology" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Waters_BEH_technology_c07876b8a3.jpg 170w," sizes="100vw" width="1050" height="964"><h5>CSH - Charged Surface Hybrid Particle Technology</h5>ACQUITY UPLC CSH™ 1.7 µm fully porous columns provide superior peak shape for basic analytes when using low ionic strength acidic mobile phases (e.g. 0.1% formic acid). With CSH Technology, the controlled low-level positive surface charge provides exceptional peak shape for basic analytes which can be achieved without the use of ion pairing reagents. Typically reversed-phase bonded phases have poor peak shape for basic compounds in formic acid even at analytical mass loads. Built on the rugged Ethylene Bridged Hybrid (BEH) particle, ACQUITY UPLC CSH phases can withstand the toughest operating conditions.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Waters_CSH_technology_ff4ddc1708.jpg" alt="Waters: CSH particle technology" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Waters_CSH_technology_ff4ddc1708.jpg 169w," sizes="100vw" width="1049" height="968"><h5>HSS - High Strength Silica (HSS) Particle Technology</h5>ACQUITY UPLC HSS 1.8 µm fully porous columns provide expected silica particle-like performance to the UPLC family. The HSS particles’ high surface area, and lower pore volume provide increased retentivity over the hybrid particles. This robust particle technology is available in five uniquely different bonded phases, which truly maximize the selectivity space. The wide array of bonded phases associated with ACQUITY UPLC HSS Columns enable traditional hydrophobic reversed-phase interactions along with dipole-dipole interactions, aromatic interactions, and hydrogen bonding interactions.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Waters_HSS_technology_b12d3ddfab.jpg" alt="Waters: HSS particle technology" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Waters_HSS_technology_b12d3ddfab.jpg 162w," sizes="100vw" width="975" height="936"><h4>Get superior peak shape for basic analytes</h4>Reversed-phase bonded phases typically have poor peak shape for basic compounds when using formic acid, even at analytical mass loads. However, ACQUITY UPLC CSH Columns are the exception. These rugged UPLC Columns provide superior peak shape for basic analytes with formic acid or other low ionic-strength, acidic mobile phases. The controlled, low-level, positive surface charge bonded to the ethylene-bridged hybrid (BEH) particles provides excellent peak shape for bases—without the need for the use of ion-pairing reagents.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Waters_Analysis_of_ziprasidone_peroxide_degradation_on_an_ACQUITY_UPLC_CSH_C18_Column_56909f1dc8.jpeg" alt="Waters: Analysis of ziprasidone peroxide degradation on an ACQUITY UPLC CSH C18 Column" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Waters_Analysis_of_ziprasidone_peroxide_degradation_on_an_ACQUITY_UPLC_CSH_C18_Column_56909f1dc8.jpeg 245w," sizes="100vw" width="1024" height="485"><h4>The ruggedness you want, the repeatability you need</h4>ACQUITY UPLC BEH 1.7 µm fully porous columns provide superior analyte peak shape, efficiency, and chemical stability to any separation. ACQUITY UPLC BEH Columns are available in both reversed-phase and HILIC separation modes, with chemistries that provide selectivities for a wide range of compounds. With the ruggedness to operate at extreme pH conditions, ACQUITY UPLC BEH Columns enable separation scientists to use a wide pH range to influence retention, selectivity, and sensitivity for ionizable compounds.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Waters_ACQUITY_UPLC_BEH_Columns_can_be_used_at_the_extremes_of_mobile_phase_p_H_1_12_to_enhance_retention_and_specificity_for_complex_samples_that_include_mixtures_of_acidic_basic_and_neutral_analytes_5104d9a155.jpeg" alt="Waters: ACQUITY UPLC BEH Columns can be used at the extremes of mobile phase pH (1-12) to enhance retention and specificity for complex samples that include mixtures of acidic, basic, and neutral analytes." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Waters_ACQUITY_UPLC_BEH_Columns_can_be_used_at_the_extremes_of_mobile_phase_p_H_1_12_to_enhance_retention_and_specificity_for_complex_samples_that_include_mixtures_of_acidic_basic_and_neutral_analytes_5104d9a155.jpeg 195w," sizes="100vw" width="1024" height="823"><h4>Achieve flexibility in method development</h4>Chromatographic laboratories need to quickly and easily develop robust methods that are compatible with all modern chromatographic detection modes and transferrable to laboratories and sites that operate different LC system platforms. With ACQUITY UPLC CSH and XSelect Columns, method development scientists in all application areas can achieve a wide range of selectivities without compromising performance across attributes, including superior peak shape for basic compounds, low column bleeds, excellent batch-to-batch reproducibility, and high efficiency.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Waters_CSH_Columns_offer_a_wide_range_of_selectivity_differences_large_S_values_733305abf8.jpeg" alt="Waters: CSH Columns offer a wide range of selectivity differences (large S-values)." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Waters_CSH_Columns_offer_a_wide_range_of_selectivity_differences_large_S_values_733305abf8.jpeg 136w," sizes="100vw" width="1024" height="1173">

Products from category C4 HPLC columns distributed by Waters Corporation (Europe) - page 1

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