<div><p><strong>Understanding how to read the resulting data of high-performance liquid chromatography (HPLC) helps turn raw detector output into confident decisions about purity, identity, and assay results. When you know how to read HPLC peaks and baselines, you can quickly spot problems, verify method performance, and support regulatory‑ready reports.</strong></p></div><div><div><div><div><h3><strong>What is an HPLC Chromatogram?</strong></h3></div></div></div></div><div><p>An HPLC chromatogram is a plot of detector signal versus time that shows how each compound in your sample moves through the column and reaches the detector. Every peak corresponds to a different component, with the position on the time axis giving its retention time and the peak size relating to concentration.</p><p>In routine work, you read retention time to confirm identity and rely on peak area or height for concentration, so learning how to read an HPLC chromatogram is essential for everyday assay workflows.</p></div><div><div><div><div><h3><strong>Why Is It Important to Read HPLC Chromatograms Correctly?</strong></h3><p>Reading HPLC results correctly matters because retention time and peak response are key parameters for separating, identifying, and quantifying compounds in complex mixtures. Misreading the baseline or peak shape can distort area integration, which affects assay accuracy and impurity quantitation.</p><p>Good <a target="_blank" rel="noopener noreferrer" href="https://www.phenomenex.com/resources/knowledge-center/hplc-knowledge-center/what-are-chromatograms"><strong>chromatogram</strong></a> interpretation also helps you detect method drift early, keep system suitability within limits, and avoid costly repeat injections or failed batches.</p></div></div></div></div><div><div><div><div><h3><strong>Key Components of an HPLC Chromatogram</strong></h3></div></div></div></div><div><p>Before you interpret a run, you must recognize the fundamental parts of a chromatogram. Each visual element gives you specific data about the separation and the analytes present in your sample.</p><h4><strong>Baseline</strong></h4><p>The baseline is the detector signal when no analyte peak is eluting, and a stable, flat baseline makes integration and quantification reliable. More detailed descriptions of baseline noise and drift are covered in the troubleshooting section below. In a nutshell, it is enough to note that any instability can affect how confidently you integrate and compare peaks.</p><h4><strong>Peaks</strong></h4><p>Peaks represent eluting analytes and appear as Gaussian‑like shapes rising above the baseline. Symmetric peaks with clear separation are easier to integrate and give more reliable responses for quantitative work.</p><h4><strong>Retention Time</strong></h4><p>Retention time, <i>t</i><sub>R</sub>, is the time from injection until the apex of a peak, reflecting how long an analyte spends in the column compared with the mobile phase. The solvent front or void peak corresponds to the dead time, <i>t</i><sub>0</sub>, which is the passage of unretained material through the system.</p><h4><strong>Peak Area and Height</strong></h4><p>Peak area is generally more reliable than peak height for quantitative analysis, because it better reflects the total amount of analyte passing the detector. In validated methods, you relate peak area or, in some cases, peak height to concentration through calibration curves and internal standards.</p><h4><strong>Resolution</strong></h4><p>Resolution describes how well two peaks are separated and depends on efficiency, selectivity, and retention. Adequate resolution means peaks do not overlap significantly, which improves identification confidence and quantification for closely eluting impurities.</p><h4><strong>Dead Time (t₀)/Void Time</strong></h4><p>Dead time, <i>t</i><sub>0</sub>, or hold‑up time, <i>t</i><sub>M</sub> (or void time), is the time taken by unretained species or the mobile phase front to pass through the column and reach the detector. You use <i>t</i><sub>0</sub> as the reference for calculating capacity factor and for assessing how strongly analytes interact with the stationary phase.</p></div><div><div><div><div><h3><strong>Step‑by‑Step Guide to Reading an HPLC Chromatogram</strong></h3></div></div></div></div><div><p>Interpreting your data requires a systematic approach to guarantee you capture all critical details. Follow this sequential process to evaluate your chromatographic results confidently and accurately.</p><h4><strong>Identify the Baseline Stability</strong></h4><p>Start by checking if the baseline is flat or if you see random noise and slow drift across the run. Significant drift or high noise suggests issues with temperature control, solvent quality, or detector stability, which must be addressed before trusting quantitation.</p><h4><strong>Locate and Count Peaks</strong></h4><p>Next, scan the chromatogram to locate all distinct peaks above the baseline and note their relative sizes. Counting peaks versus expectations from standards or sample composition helps you detect co‑elution, extra peaks, or missing analytes.</p><h4><strong>Determine Retention Time</strong></h4><p>Measure retention time, <i>t</i><sub>R</sub>, for each peak and record these values alongside known standards or system-suitability data. Consistent <i>t</i><sub>R</sub> values within defined windows support correct identification, while larger shifts can indicate changes in temperature, mobile phase composition, or flow rate.</p><h4><strong>Calculate Capacity Factor (k') Using t<sub>M</sub> and t<sub>R</sub></strong></h4><p>Capacity factor, <i>K'</i> (or retention factor), describes how much longer an analyte is retained compared with unretained material and is calculated from the chromatogram. Using the dead time, <i>t</i><sub>M</sub>, (void peak) and analyte retention time, <i>t</i><sub>R</sub>, you apply<strong> </strong><i><strong>k</strong></i><strong> = (</strong><i><strong>t</strong></i><strong><sub>R</sub> – </strong><i><strong>t</strong></i><strong><sub>M</sub>)/</strong><i><strong>t</strong></i><strong><sub>M</sub></strong> to assess whether the analyte is sufficiently retained under the chosen conditions.</p><p>Knowing how to analyze HPLC results with capacity factor helps you judge if peaks elute too close to <i>t</i><sub>0</sub>, or spend an appropriate time interacting with the column, which guides method refinement.</p><h4><strong>Analyze Peak Area for Quantification (H3)</strong></h4><p>For quantification, integrate each peak to obtain the area and compare it with calibration standards or internal standards to calculate concentration. Reliable peak area measurements depend on good baseline definition and stable detector response, so always verify baseline quality before finalizing your measurements.</p><h4><strong>Evaluate Peak Shape and Resolution</strong></h4><p>Assess whether peaks are symmetric or show tailing, fronting, or broadening, and examine spacing between adjacent peaks for resolution. Changes in peak shape across the chromatogram can reveal extra‑column effects, packed bed issues, or interaction with active sites on the stationary phase.</p><p>If you see persistent problems, review your <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/lcms/products?category=48&amp;manufacturerItems=50"><strong><u>HPLC column</u></strong></a> choice, sample preparation, and gradient or isocratic settings to refine separation.</p></div><div><div><div><div><h3><strong>Common Problems in HPLC Chromatograms and How to Identify Them</strong></h3><p>Even well-developed methods can degrade over time and produce visual cues that signal system or chemistry faults. Recognizing these characteristic peak and baseline distortions is your first step in troubleshooting.</p><h4><strong>Peak Tailing</strong></h4><p><a target="_blank" rel="noopener noreferrer" href="https://www.phenomenex.com/resources/knowledge-center/hplc-knowledge-center/how-to-reduce-peak-tailing-in-hplc"><strong><u>Peak tailing</u></strong></a> appears when the right side of a peak stretches out into a long tail instead of dropping back to the baseline symmetrically. On the chromatogram, the trailing edge slopes slowly and the peak looks skewed to the left, which makes integration boundaries less obvious and can hint at dispersion or secondary interactions. You can reduce tailing by minimizing extra‑column volume and checking column packing and active sites.</p><h4><strong>Peak Fronting</strong></h4><p><a target="_blank" rel="noopener noreferrer" href="https://www.phenomenex.com/resources/knowledge-center/hplc-knowledge-center/peak-fronting"><strong><u>Peak fronting</u></strong></a> shows a steep leading edge and a compressed front portion of the peak, so the apex seems pulled forward relative to the rest of the peak profile. Visually, the peak looks like it is leaning in the direction of flow and the front overlaps more strongly with neighboring peaks, which can distort apparent purity for fast‑eluting components.</p><p>Consider lowering sample load or injection volume and matching diluent strength to the mobile phase, and when fronting persists, consult Phenomenex resources on <a target="_blank" rel="noopener noreferrer" href="https://www.phenomenex.com/resources/knowledge-center/gc-knowledge-center/peak-shape-problems-tailing-peaks"><strong><u>peak-shape problems</u></strong></a>.</p><h4><strong>Noise and Drift</strong></h4><p>Baseline noise appears as small, rapid fluctuations around the baseline that make it harder to see low‑level peaks. Baseline drift shows up as a slow rise or fall of the baseline across the run, so the line no longer stays flat; this can cause apparent changes in peak height and shifts in where you draw integration baselines. Simple checks like improving solvent degassing, stabilizing temperature, and cleaning detector flow cells help reduce noise and drift.</p><h4><strong>Co‑Elution</strong></h4><p>Co‑elution is easy to spot when two peaks do not fully separate and instead form a shoulder or merged profile on the chromatogram.You may see one peak with a plateau or a visible kink where two components overlap, and the valley between them does not return to the baseline, which complicates assignments for closely eluting impurities. To resolve co‑elution, adjust selectivity by changing mobile phase composition, gradient profile, or column chemistry.</p><h4><strong>Broad Peaks</strong></h4><p>Broad peaks have a noticeably wider base and lower height compared with well‑focused peaks of similar are. They often span more time units on the x‑axis and show gentle slopes on both sides, indicating band spreading that reduces resolution and makes small shoulders harder to detect. Narrowing broad peaks usually involves reducing extra‑column volumes and confirming column performance and particle size suitability.</p><h4><strong>Retention-Time Shifting</strong></h4><p>Retention-time shifting is seen when all peaks move earlier or later in the chromatogram compared with previous runs, while their shapes remain similar. When you overlay chromatograms, consistent shifts in peak positions along the time axis, often on the order of a few percent, indicate changes in conditions such as temperature or mobile phase that must be tracked carefully. Fixing retention time shifts starts with stabilizing temperature and verifying mobile phase composition and flow rate settings across runs.</p></div></div></div></div><div><div><div><div><h3><strong>Tips for Accurate HPLC Chromatogram Interpretation</strong></h3></div></div></div></div><div><p>To read HPLC chromatograms accurately, maintain a stable temperature, use well‑degassed mobile phases, and keep detector flow cells and optics clean. Regularly check capacity factor and selectivity values against method expectations, and verify that resolution is adequate for critical pairs before accepting results.</p><p>When retention times drift or peak shapes degrade, review your <a target="_blank" rel="noopener noreferrer" href="https://www.phenomenex.com/resources/knowledge-center/gc-knowledge-center/understanding-retention-time"><strong><u>retention-time</u></strong></a> trends alongside system maintenance logs so you can correct problems early.</p></div><div><div><div><div><h3><strong>FAQs on Reading HPLC Chromatograms</strong></h3></div></div></div></div><div><h4><strong>How Do You Calculate Capacity Factor (k') from a Chromatogram?</strong></h4><p>Capacity factor, <i>k</i>, is calculated using the analyte retention time, [Equation], and the dead time, <i>t</i><sub>R</sub>, measured from the unretained peak. Apply <i>k</i> = (<i>t</i><sub>R</sub> – <i>t</i><sub>M</sub>)/<i>t</i><sub>M</sub>, so higher k values indicate stronger interactions with the stationary phase and longer retention.</p><h4><strong>How Is Selectivity (α) Calculated Using Chromatogram Data?</strong></h4><p>Selectivity (α) describes how well two components are separated and is defined as the ratio of their retention factors, α = <i>k</i><sub>2</sub>/<i>k</i><sub>1</sub>, for peaks, where <i>k</i><sub>2</sub> &gt; <i>k</i><sub>1</sub>. Values higher than 1.2 show separation, and larger α values correspond to better selectivity between the peaks.</p><h4><strong>What Does Peak Area Indicate in HPLC?</strong></h4><p>Peak area reflects the total amount of analyte that reaches the detector and is generally more reliable than peak height for quantitative work. Build calibration curves that relate peak area to concentration, then apply them only when the baseline and detector response remain stable across all injections.</p><h4><strong>How Is Retention Time Used in HPLC Analysis?</strong></h4><p>Retention time is used as a qualitative index because each compound elutes at a characteristic time when conditions are held constant. Compare sample retention times with those of standards and then pair that information with peak area or height to confirm identity and calculate concentration in routine analyses.</p></div>

How to Read an HPLC Chromatogram: Step‑by‑Step Guide to Interpreting Results

<p><i><span><strong>Are you currently using single-column batch chromatography to isolate and purify target compounds, but struggling with high solvent demand, low product concentration, or limited throughput? Simulated Moving Bed chromatography offers an alternative approach that can address many of these limitations through continuous multi-column separation.</strong></span></i></p><h4><span><strong>What is Simulated Moving Bed Chromatography (SMB)?</strong></span></h4><p><span>Simulated Moving Bed (SMB) chromatography is a continuous multi-column separation technique designed to make more efficient use of the stationary phase while minimizing solvent consumption. It is particularly well suited to the purification of binary and pseudo-binary mixtures, including enantiomers, sugars, petrochemical products, and fine chemicals.</span></p><h4><span><strong>Conventional Batch Chromatography</strong></span></h4><p><span>In traditional batch chromatography, the sample is introduced onto a single chromatographic column and transported through the stationary phase by the mobile phase. Individual compounds interact with the stationary phase to different extents and therefore travel through the column at different rates:</span></p><ul><li><span>Weakly retained compounds migrate more rapidly.</span></li><li><span>Strongly retained compounds move through the column more slowly.</span></li></ul><p><span>The separated substances consequently leave the column at different retention times and can be collected as individual fractions (Fig. 1). Before a new sample is normally introduced, the previous sample must be completely eluted and the column prepared for the next separation.</span></p><p><span>Although single-column batch chromatography is versatile and comparatively easy to operate, several disadvantages become increasingly important at production scale. The stationary phase is not continuously involved in useful separation, which can limit productivity. Other drawbacks include substantial solvent consumption, diluted product fractions, repeated column regeneration, and potential loss of valuable product.</span></p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Figure_1_Single_column_separation_A_fast_eluting_component_B_retaining_component_cda8ef66ef.jpg" alt="KNAUER: Figure 1: Single column separation; A – fast eluting component, B – retaining component" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Figure_1_Single_column_separation_A_fast_eluting_component_B_retaining_component_cda8ef66ef.jpg 76w," sizes="100vw" width="394" height="800"></p><h4><span><strong>From True Moving Bed to SMB</strong></span></h4><p><span>The principle behind SMB originates from the theoretical <strong>True Moving Bed (TMB)</strong> process. In an ideal TMB system, the liquid mobile phase and the solid stationary phase continuously travel in opposite directions. This counter-current arrangement takes advantage of differences in the affinity of individual compounds toward the two phases.</span></p><p><span>Consider a binary mixture containing components A and B. Component A interacts more strongly with the stationary phase, whereas component B is less strongly retained and preferentially follows the liquid mobile phase. Under appropriate operating conditions, the two substances effectively migrate in opposite directions and can be collected continuously through separate outlets (Fig. 2).</span></p><p><span>While this concept is highly efficient from a theoretical perspective, continuously moving a packed solid chromatographic adsorbent is technically difficult to realize.</span></p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Figure_2_True_Moving_Bed_concept_e1eac66028.jpg" alt="KNAUER: Figure 2: True Moving Bed concept" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Figure_2_True_Moving_Bed_concept_e1eac66028.jpg 186w," sizes="100vw" width="954" height="800"></p><p><span>Four process ports divide the system into four functional zones (Zone I–IV):</span></p><ol><li><span>Eluent (desorbent) inlet</span></li><li><span>Extract outlet</span></li><li><span>Feed inlet</span></li><li><span>Raffinate outlet</span></li></ol><p><span>Feed and eluent are introduced continuously, while two product streams are simultaneously withdrawn:</span></p><ul><li><span><strong>Extract</strong> – the strongly retained, later-eluting component</span></li><li><span><strong>Raffinate</strong> – the less strongly retained, earlier-eluting component</span></li></ul><h4><span><strong>The Four Functional Zones</strong></span></h4><p><span>Each of the four zones has a defined purpose and operates at its own internal flow rate (VI–VIV):</span></p><ul><li><span><strong>Zone I</strong> regenerates the stationary phase.</span></li><li><span><strong>Zone II</strong> prevents the weakly retained component from entering the extract stream.</span></li><li><span><strong>Zone III</strong> prevents the strongly retained component from contaminating the raffinate.</span></li><li><span><strong>Zone IV</strong> enables recovery and internal reuse of the remaining solvent.</span></li></ul><h4><span><strong>How is the TMB Principle Implemented in SMB?</strong></span></h4><p><a target="_blank" rel="noopener noreferrer" href="https://www.knauer.net/smb"><span>SMB</span></a><span> eliminates the need to physically move the stationary phase. Instead, the adsorbent remains fixed inside the chromatographic columns, while the positions of the liquid inlet and outlet ports are periodically shifted.</span></p><p><span>From the perspective of these moving connection points, the stationary phase appears to travel in the opposite direction to the liquid phase. SMB therefore reproduces the counter-current behavior of a TMB system without physically transporting the packed adsorbent (Fig. 3).</span></p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Figure_3_Transfer_TMB_concept_to_SMB_concept_e4b8905269.jpg" alt="KNAUER: Figure 3: Transfer TMB concept to SMB concept" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Figure_3_Transfer_TMB_concept_to_SMB_concept_e4b8905269.jpg 245w," sizes="100vw" width="1372" height="800"></p><p><span>A typical SMB setup consists of several chromatographic columns arranged in a closed loop. A standard configuration often uses eight columns, although the number can be adapted according to the application.</span></p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Figure_4_SMB_concept_fb005cdfa1.jpg" alt="KNAUER: Figure 4: SMB concept" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Figure_4_SMB_concept_fb005cdfa1.jpg 195w," sizes="100vw" width="1001" height="800"></p><p><span>After a predefined switching time, all inlet and outlet positions move forward by one column in the direction of the mobile-phase flow. The columns themselves stay in place, but their functional roles within the process change.</span></p><p><span>By repeatedly shifting the ports, the system creates the effect of a stationary phase moving counter-currently to the mobile phase. With eight columns, eight switching steps are required to complete one full SMB cycle.</span></p><p><span>Following an initial transition period, the process reaches a cyclic steady state. Concentrations continue to fluctuate during individual switching intervals, but the overall concentration profile repeats after every complete cycle.</span></p><p><span>Increasing the number of columns and reducing the size of individual switching steps allows the SMB system to reproduce ideal TMB behavior more closely. Systems containing fewer columns exhibit more pronounced discrete switching effects and can require more sophisticated dynamic modeling during process development.</span></p><h3><span><strong>What are the Main Advantages of SMB?</strong></span></h3><h4><span><strong>1. Continuous Operation and Higher Productivity</strong></span></h4><p><span>The key benefit of SMB chromatography is continuous operation. Feed and eluent enter the system continuously, while purified extract and raffinate streams are removed at the same time.</span></p><p><span>As a result, SMB systems can operate for prolonged periods—from several days to even several weeks—with very limited interruption.</span></p><p><span>Because several chromatographic columns perform different separation functions simultaneously, the stationary phase is utilized much more effectively than in conventional batch chromatography. This can translate into higher productivity, improved process efficiency, and a continuous supply of purified product.</span></p><h4><span><strong>2. Reduced Solvent Consumption</strong></span></h4><p><span>Conventional batch chromatography can require substantial volumes of mobile phase to achieve separation and product recovery. The collected fractions are often highly diluted, creating an additional need for downstream concentration.</span></p><p><span>SMB maintains concentration profiles within the circulating system and uses the mobile phase more efficiently. Partial internal recycling of solvent is an inherent part of the process.</span></p><p><span>Lower solvent consumption can lead to:</span></p><ul><li><span>Reduced raw-material costs</span></li><li><span>Lower volumes of liquid waste</span></li><li><span>Reduced energy requirements for solvent evaporation</span></li><li><span>More concentrated product streams and less downstream concentration</span></li></ul><h4><span><strong>3. High Recovery and Reproducible Product Quality</strong></span></h4><p><span>Once the process reaches cyclic steady state, SMB can continuously generate product streams with stable and reproducible composition.</span></p><p><span>Additional advantages can include high product recovery, lower product dilution, more efficient use of the stationary phase, and straightforward integration into continuous manufacturing strategies.</span></p><h4><span><strong>What are the Differences Between Batch LC and SMB?</strong></span></h4><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_differences_between_batch_LC_and_SMB_eba3897f65.jpg" alt="KNAUER: Differences between batch LC and SMB" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_differences_between_batch_LC_and_SMB_eba3897f65.jpg 245w," sizes="100vw" width="1061" height="638"></p><h4><span><strong>Where is SMB Used?</strong></span></h4><p><span>SMB technology is established across several industries and can be applied to purification processes ranging from gram-scale production to several tons per day (Fig. 5).</span></p><p><span>Typical and emerging applications include:</span></p><ul><li><span>Sugar purification</span></li><li><span>Petrochemical separations</span></li><li><span>Chiral separations</span></li><li><span>Fine chemical production</span></li><li><span>Pharmaceutical intermediates</span></li><li><span>Selected biomolecule separations</span></li></ul><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Figure_5_SMB_application_areas_7109ff703f.jpg" alt="KNAUER: Figure 5: SMB application areas; author's illustration" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Figure_5_SMB_application_areas_7109ff703f.jpg 245w," sizes="100vw" width="1500" height="512"></p><h4><span><strong>Limitations of SMB</strong></span></h4><p><span>Although SMB can provide substantial advantages, it is not necessarily the ideal solution for every chromatographic separation.</span></p><p><span>The instrumentation and process configuration are more complex than conventional single-column chromatography. Several pumps, valves, columns, and liquid pathways must be controlled precisely. Successful method development therefore requires a solid understanding of adsorption equilibria, mass-transfer effects, and fluid dynamics.</span></p><p><span>Classical four-zone SMB is primarily intended for binary and pseudo-binary separations. More complicated mixtures may require modified SMB configurations, additional purification steps, or multiple coupled SMB systems.</span></p><p><span>SMB is generally most economically attractive when relatively large quantities of a consistent feed material are processed continuously over extended periods.</span></p><p><span>Batch chromatography can remain the better option for small-scale production, frequent changes between products, complex multicomponent mixtures, or applications that depend on flexible gradient separations.</span></p><h4><span><strong>Conclusion</strong></span></h4><p><span>Simulated Moving Bed chromatography converts the theoretical counter-current principle of True Moving Bed separation into a practical continuous chromatographic process. Instead of physically transporting the stationary phase, SMB periodically changes the positions of the feed, eluent, extract, and raffinate connections. This reproduces the effect of counter-current movement between stationary and mobile phases.</span></p><p><span>Compared with conventional batch chromatography, SMB can provide higher productivity, more efficient stationary-phase utilization, substantially lower solvent consumption, and more concentrated product streams. Continuous operation makes the technology particularly attractive for demanding large-scale binary separations, including the purification of pharmaceutical enantiomers.</span></p><p><span>Although successful SMB implementation requires accurate process data, careful method development, and precise control of operating conditions, the technology demonstrates how an idealized chromatographic principle can be transformed into a robust and efficient industrial separation strategy.</span></p>

Simulated Moving Bed Chromatography: Efficient Continuous Separation

News from LabRulezLCMS Library - Week 44, 2026

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Everything from the world of analytical chemistry in one place. We connect people in solving their problems. At Labrulez you will find all the necessary information easily, quickly and clearly. Stop searching and start finding.

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Phenomenex is a global technology leader committed to developing novel analytical chemistry solutions that solve the separation and purification challenges of researchers in industrial, government and academic laboratories.

Phenomenex

Based in Berlin, KNAUER is a medium-sized, owner-managed company that has been serving the sciences since 1962. We develop and manufacture scientific instruments of superior quality for liquid chromatography, including: Analytical HPLC/UHPLC, Preparative HPLC, Fast protein liquid chromatography (FPLC), Multi-column chromatography/Simulated moving bed (SMB) chromatography. High pressure dosing, in-line detection systems, and osmometry are additional business areas.

KNAUER

KNAUER RF-20A Fluorescence Detector

High-sensitivity fluorescence detector for HPLC with 200–650 nm wavelength range, ≥1200 S/N ratio, fast 10 ms response, and excellent trace-level detection performance.

<p><strong>The KNAUER RF-20A Fluorescence Detector is a highly sensitive fluorescence detector designed for demanding HPLC applications requiring exceptional selectivity and trace-level detection. Covering a wavelength range from 200 to 650 nm, the RF-20A delivers outstanding sensitivity, excellent reproducibility, and reliable operation for both routine and advanced chromatographic analyses.</strong></p><p>With a signal-to-noise ratio of at least 1200 for the water Raman band, the detector is ideally suited for trace-level determinations in pharmaceutical, environmental, food, and biochemical applications. A fast 10 ms response time supports high-speed chromatography without compromising chromatographic resolution. Time-programmed wavelength switching allows optimal excitation and emission settings throughout the run, enabling highly sensitive multi-component analysis.</p><h3><strong>Key Features</strong></h3><ul><li>High-sensitivity fluorescence detector for HPLC applications</li><li><strong>Wavelength range from 200 to 650 nm</strong></li><li><strong>Signal-to-noise ratio ≥1200</strong> (water Raman band)</li><li>Excellent performance for trace-level analysis</li><li><strong>Fast 10 ms response time</strong></li><li>Time-programmable wavelength switching</li><li>Multi-component analysis at optimal wavelengths</li><li><strong>Long-life xenon lamp</strong> (approx. 2,000 hours)</li><li>Front-accessible lamp and flow cell</li><li>No optical adjustment required after lamp replacement</li><li>Minimal maintenance requirements</li><li>Stand-alone operation via keypad and display</li><li><strong>Compatible with ClarityChrom®, OpenLAB®, and PurityChrom® software</strong></li><li>Easy integration into existing LC systems</li></ul><h3><strong>Technical Specifications</strong></h3><h4><strong>Detection System</strong></h4><ul><li><strong>Detection channels: </strong>1</li><li><strong>Number of signals:</strong> 1</li><li><strong>Light source: </strong>Xenon lamp</li><li><strong>Wavelength range:</strong> 200–650 nm</li><li><strong>Spectral bandwidth:</strong> 20 nm</li><li><strong>Wavelength accuracy:</strong> ±2 nm</li><li><strong>Wavelength precision:</strong> ±0.2 nm</li></ul><h4><strong>Sensitivity</strong></h4><ul><li><strong>Signal-to-noise ratio: </strong>≥1200 (water Raman band)</li><li><strong>Sensitivity settings:</strong><ul><li>HIGH (×1)</li><li>MED (×32)</li><li>LOW (×1024)</li></ul></li></ul><h4><strong>Flow Cell</strong></h4><ul><li>Standard flow cell included</li><li><strong>Flow cell volume: </strong>12 µL</li><li><strong>Wetted materials:</strong><ul><li>SUS316L stainless steel</li><li>PTFE</li><li>Quartz</li></ul></li></ul><h4><strong>Signal Processing</strong></h4><ul><li><strong>Response time: </strong>10 ms</li><li><strong>Gain settings: </strong>×1, ×4, ×16</li></ul><h4><strong>Functions</strong></h4><ul><li>Autozero function</li><li>Baseline shift function</li><li>Time-programmed wavelength switching</li></ul><h4><strong>Communication</strong></h4><ul><li>RS-232 interface</li><li>Analog output</li><li>Software control</li><li>Stand-alone operation via keypad and display</li></ul><h4><strong>Environmental Conditions</strong></h4><ul><li><strong>Operating temperature:</strong> 4–35 °C</li><li><strong>Relative humidity: </strong>20–85% (non-condensing)</li></ul><h4><strong>Power and Dimensions</strong></h4><ul><li><strong>Power supply: </strong>AC 220–240 V</li><li><strong>Frequency: </strong>50/60 Hz</li><li><strong>Power consumption: </strong>400 VA</li><li><strong>Dimensions (W × H × D):</strong> 260 × 210 × 420 mm</li><li><strong>Weight:</strong> 16 kg</li></ul><h3><strong>Applications</strong></h3><ul><li>Pharmaceutical analysis</li><li>Impurity profiling</li><li>Environmental monitoring</li><li>Food and beverage testing</li><li>Amino acid analysis</li><li>Vitamin analysis</li><li>PAH analysis</li><li>Biomolecule detection</li><li>Trace contaminant determination</li><li>Research and quality control laboratories</li></ul>

KNAUER RF-20Axs Fluorescence Detector

High-sensitivity fluorescence detector with 200–750 nm range, temperature-controlled flow cell, ≥2000 S/N ratio, and exceptional performance for trace-level HPLC analysis.

<p><strong>The KNAUER RF-20Axs Fluorescence Detector is the high-performance version of the </strong><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/2430"><strong>RF-20A fluorescence detector</strong></a><strong> series, designed for laboratories requiring maximum sensitivity, exceptional reproducibility, and advanced validation capabilities. Covering a wavelength range from 200 to 750 nm, the detector supports both routine and demanding high-performance HPLC applications.</strong></p><p>With a signal-to-noise ratio of at least 2000 for the water Raman band, the RF-20Axs is ideally suited for trace-level analysis. The temperature-controlled flow cell with integrated cooling function ensures outstanding stability, reproducibility, and sensitivity, even during long analytical sequences. The detector’s fast 10 ms response time supports ultra-fast chromatography without compromising chromatographic resolution.</p><p>The RF-20Axs enables highly sensitive multi-component analysis through programmable wavelength switching during a chromatographic run. An integrated low-pressure mercury lamp allows convenient verification of wavelength accuracy, supporting validation and compliance requirements. Both the xenon lamp and flow cell are easily accessible from the front panel, and lamp replacement requires no optical adjustment. Combined with a lamp lifetime of approximately 2,000 hours, this minimizes downtime and operating costs.</p><h3><strong>Key Features</strong></h3><ul><li>High-sensitivity fluorescence detector for <strong>HPLC applications</strong></li><li>Wavelength range <strong>from 200 to 750 nm</strong></li><li><strong>Signal-to-noise ratio ≥2000</strong> (water Raman band)</li><li>Designed for trace-level analysis</li><li>Temperature-controlled flow cell with cooling function</li><li><strong>Fast 10 ms response time</strong></li><li>Programmable wavelength switching during analysis</li><li>Simultaneous multi-component analysis at optimal wavelengths</li><li>Integrated low-pressure mercury lamp for wavelength verification</li><li><strong>Long-life xenon lamp </strong>with approximately <strong>2,000 operating hours</strong></li><li>Front-accessible lamp and flow cell</li><li>No optical realignment required after lamp replacement</li><li>Advanced validation and support functions</li><li>Stand-alone operation via keypad and display</li><li>Compatible with <strong>ClarityChrom®, OpenLAB®, and PurityChrom® software</strong></li><li>Easy integration into virtually any LC system</li></ul><h3><strong>Technical Specifications</strong></h3><h4><strong>Detection System</strong></h4><ul><li><strong>Detection channels: </strong>2</li><li><strong>Number of signals: </strong>2</li><li><strong>Light source:</strong><ul><li>Xenon lamp</li><li>Low-pressure mercury lamp for wavelength accuracy verification</li></ul></li><li><strong>Wavelength range: </strong>200–750 nm</li><li><strong>Spectral bandwidth: </strong>20 nm</li><li><strong>Wavelength accuracy:</strong> ±2 nm</li><li><strong>Wavelength precision: </strong>±0.2 nm</li></ul><h4><strong>Sensitivity</strong></h4><ul><li><strong>Signal-to-noise ratio: </strong>≥2000 (water Raman band)</li><li><strong>Sensitivity settings:</strong><ul><li>HIGH (×1)</li><li>MED (×32)</li><li>LOW (×1024)</li></ul></li></ul><h4><strong>Flow Cell</strong></h4><ul><li>Standard flow cell included</li><li>Temperature-controlled flow cell</li><li>Integrated cooling function</li><li><strong>Flow cell volume:</strong> 12 µL</li><li><strong>Wetted materials:</strong><ul><li>SUS316L stainless steel</li><li>PTFE</li><li>Quartz</li></ul></li></ul><h4><strong>Signal Processing</strong></h4><ul><li><strong>Response time: </strong>10 ms</li><li><strong>Gain settings: </strong>×1, ×4, ×16</li></ul><h4><strong>Functions</strong></h4><ul><li>Autozero function</li><li>Baseline shift function</li><li>Time-programmed wavelength switching</li><li>Wavelength accuracy verification using integrated mercury lamp</li></ul><h4><strong>Communication</strong></h4><ul><li>RS-232 interface</li><li>Analog output</li><li>Software control</li><li>Stand-alone operation via keypad and display</li></ul><h4><strong>Environmental Conditions</strong></h4><ul><li><strong>Operating temperature:</strong> 4–35 °C</li><li><strong>Relative humidity:</strong> 20–85% (non-condensing)</li></ul><h4><strong>Power and Dimensions</strong></h4><ul><li><strong>Power supply: </strong>AC 220–240 V</li><li><strong>Frequency:</strong> 50/60 Hz</li><li><strong>Power consumption: </strong>400 VA</li><li><strong>Dimensions (W × H × D): </strong>260 × 210 × 420 mm</li><li><strong>Weight:</strong> 18 kg</li></ul><h3><strong>Applications</strong></h3><ul><li>Trace-level pharmaceutical analysis</li><li>Impurity profiling</li><li>Environmental monitoring</li><li>Food safety testing</li><li>Amino acid analysis</li><li>Vitamin analysis</li><li>PAH analysis</li><li>Biomolecule detection</li><li>Fluorescent labeling applications</li><li>Research and quality control laboratories</li></ul>

Products from category Fluorescence detectors (FLD) - page 1

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