Pesticides and biocides are widely used in agriculture, building materials, and urban gardening to control pests and protect crops and public health. While much attention has been paid to pesticide residues in food, water, and outdoor environments, far less is known about their presence inside homes, where people spend the majority of their time. A new RECETOX study published in Indoor Environments addresses this gap by examining pesticides detected in house dust and their relevance for human exposure.&nbsp;The study reveals that Czech household dust commonly contains multiple pesticide residues, highlighting the persistence of both historic and current chemical use indoors. Modern pesticides were detected in 93% of homes, with two fungicides (carbendazim and propiconazole) most frequently found, while compounds related to the long‑banned pesticide DDT were present in dust from all homes, and were at higher levels in homes over 40 years old. Homes located closer to agricultural areas showed higher levels of current‑use pesticides in spring, indicating an influence of nearby farming activities. &nbsp;House dust acts as a sink for chemicals transported indoors from outdoor sources as well as from indoor use. Many pesticides can persist in dust for long periods, leading to continuous exposure in indoor spaces. This is particularly important for young children, who have higher exposure to dust from playing on the floor and mouthing toys and objects. The research underscores that indoor environments are not isolated from their surroundings. Understanding what ends up in house dust is a crucial step toward protecting public health and developing more comprehensive approaches to managing chemical risks in everyday life.&nbsp;<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/RECETOX_Vyzkum_pesticidu_v_domacim_prachu_opomijena_cesta_lidske_expozice_a9a089fd2f.jpg" alt="RECETOX: Pesticides in House Dust: An Overlooked Pathway of Human Exposure" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_RECETOX_Vyzkum_pesticidu_v_domacim_prachu_opomijena_cesta_lidske_expozice_a9a089fd2f.jpg 195w," sizes="100vw" width="738" height="591"><blockquote><h4>Original Article</h4><h4><a target="_blank" rel="noopener noreferrer" href="https://www.sciencedirect.com/science/article/pii/S2950362026000214?via%3Dihub">Legacy and current-use pesticides in indoor settled dust and association with building age and seasonality</a></h4>Paula Marcinekova, Ondřej Mikeš, Simona Rozárka Jílková, Petr Šenk, Jakub Martiník, Jan Böhm, Petra Borilova Linhartova, Lenka Andrýsková, Jana Klánová, Lisa MelymukIndoor Environ., 2026, 3, 100169<a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.1016/j.indenv.2026.100169">https://doi.org/10.1016/j.indenv.2026.100169</a>&nbsp;<h6>licensed 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>Indoor pesticide exposure is increasingly recognized as a significant contributor to pollutant exposure in residential spaces. This study investigates concentrations of legacy organochlorine pesticides (OCPs) and current-use pesticides (CUPs) in settled dust from 116 homes in the Czech Republic, in the context of their seasonal variability, relationships with building characteristics, geospatial factors, and indoor dust bacteriome diversity and composition. CUPs were detected in dust in 93% of homes, with carbendazim (84.5%), propiconazole (49.1%), atrazine (24.1%), and tebuconazole (11.2%) detected most frequently. OCPs were found in all homes. Propiconazole concentrations were significantly higher in homes with adjacent gardens, potentially reflecting its use as a biocide in outdoor building materials. CUP concentrations had clear seasonal trends, with peak levels in spring and summer, corresponding to pesticide application periods, particularly in rural environments. OCP concentrations were substantially higher in houses over 40 years old, indicating the persistence of residues from past indoor uses. While pesticide presence was ubiquitous, exposure estimates for children, under both average and high-exposure scenarios, were well below U.S. EPA reference doses (RfDs) for individual compounds; however, most homes had 3–11 pesticides in dust, raising the possibility of mixture effects. No significant associations, using a Spearman rank correlation matrix, were observed between pesticide concentrations and indoor dust bacteriome diversity and composition. These findings highlight the presence of pesticides in homes, including those in urban areas, driven by both current and historical sources, and reinforce the importance of monitoring to better understand potential exposure pathways.<h4>Instrumentation</h4><h5>1. LC–MS/MS analysis of CUPs</h5><ul><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library?instrumentationItems=27&amp;mainauthorItems=10&amp;search=1290+Series+Gradient">Agilent 1290 Series Gradient HPLC</a></li><li>Columns:<ul><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/1701">Phenomenex Luna C18</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library?instrumentationItems=34&amp;mainauthorItems=50&amp;search=SecurityGuard+C18">Phenomenex SecurityGuard C18</a></li></ul></li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library?mainauthorItems=55&amp;search=QTrap+5500%2B">SCIEX QTrap 5500+</a> (triple quadrupole MS, ESI+)</li></ul><h5>2. GC–MS/MS analysis of OCPs</h5><ul><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?instrumentationItems=1&amp;mainauthorItems=10&amp;search=8890A">Agilent 8890A GC</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?instrumentationItems=19&amp;mainauthorItems=7&amp;search=Rxi-5Sil-MS">Restek Rxi-5Sil-MS capillary column</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=7000D">Agilent 7000D triple quadrupole MS</a></li></ul>

Pesticides in House Dust: An Overlooked Pathway of Human Exposure

This technical note presents a practical troubleshooting strategy for one of the most common issues in liquid chromatography (LC): shifting retention times. The approach is based on a systematic distinction between system-related (physical) and chromatographic (chemical) causes.A key diagnostic parameter used throughout the process is the T₀ (dead time), representing an unretained peak that passes through the column without interaction.<h3>Key Concept: T₀ (Dead Time / Unretained Peak)</h3>T₀ is defined as the retention time of a compound that does not interact with the stationary phase and therefore elutes directly with the mobile phase.<h4>How to Determine T₀</h4>T₀ can be determined experimentally by adding a marker compound to the system:<ul><li>Uracil</li><li>Potassium nitrate</li></ul>These compounds are added to a blank or method and produce a measurable unretained peak used for troubleshooting.<h3>Step 1: Evaluate T₀ Behavior</h3>The first and most important step is to determine whether T₀ is constant or variable.<ul><li>Case A: T₀ is Variable (Shifting) → Indicates a system-related (physical) problem &nbsp;</li><li>Case B: T₀ is Constant → Indicates a chromatographic or chemical problem</li></ul><h3>System-Related Issues (T₀ is Variable)</h3>If T₀ is shifting, the problem is likely related to the LC system hardware or physical parameters. This is especially true when all peaks shift together in the chromatogram.<h3>Possible Causes</h3><ul><li>Incorrect Flow Rate</li><li>Pump Malfunction<ul><li>Inconsistent or unstable flow delivery can cause retention time variability.</li></ul></li><li>Incorrect Column Length<ul><li>Using a column with different dimensions than expected.</li></ul></li><li>Solvent Delivery Issues<ul><li>Empty solvent reservoir (system running dry)</li><li>Blockages or restrictions (e.g., frits, solvent lines)</li></ul></li><li>Tubing or System Volume Changes<ul><li>Changes in tubing configuration</li><li>Differences in system dwell (swell) volume</li></ul></li></ul><h3>Chromatographic / Chemical Issues (T₀ is Constant)</h3>If T₀ remains stable but only specific peaks shift, the issue is likely related to chemistry or column conditions.<h4>Possible Causes</h4><ul><li>Incorrect Stationary Phase<ul><li>Column with same dimensions but different chemistry (e.g., different silica or bonded phase)</li></ul></li><li>Ionizable Analytes Ionizable compounds exist in:<ul><li>Neutral form - More hydrophobic, retained longer on a reversed-phase column</li><li>Ionized form</li></ul>Impact of pH Small pH changes in the mobile phase can significantly affect:<ul><li>Ionization state</li><li>Retention time of specific analytes</li></ul></li><li>Mobile Phase Issues<ul><li>Old solvents</li><li>Evaporation of volatile components</li><li>Changes in composition</li></ul></li><li>4. Temperature Variations<ul><li>Temperature affects analyte–stationary phase interactions</li><li>Even small fluctuations can shift retention times</li></ul></li></ul><h3>Step-by-Step Troubleshooting Workflow</h3><ol><li>Add T₀ Marker<ol><li>Use uracil or potassium nitrate</li></ol></li><li>Monitor T₀<ol><li>Determine whether it is constant or shifting</li></ol></li><li>If T₀ is Variable → Check System<ol><li>Flow rate settings</li><li>Pump performance</li><li>Solvent levels and lines</li><li>Column dimensions</li><li>Tubing and system volume</li></ol></li><li>If T₀ is Constant → Check Chemistry<ol><li>Column phase</li><li>Mobile phase composition and pH</li><li>Solvent quality</li><li>Temperature stability</li><li>Nature of analytes (ionizable vs. non-ionizable)</li></ol></li></ol><h3>Discussion and Practical Insight</h3>This troubleshooting approach simplifies a complex problem by dividing it into two main categories:<ul><li>Physical/system-related</li><li>Chemical/chromatographic</li></ul>The use of T₀ as a diagnostic tool allows rapid identification of the problem origin, reducing unnecessary trial-and-error steps.Particular attention should be paid to ionizable compounds, as they are highly sensitive to pH variations, which can lead to significant and selective retention time shifts.<h3>Conclusion</h3>Retention time shifts in LC can be efficiently diagnosed by evaluating the behavior of the T₀ (unretained peak):<ul><li>Variable T₀ → System issue</li><li>Constant T₀ → Chromatographic/chemical issue</li></ul>By following this structured approach, analysts can quickly narrow down the root cause and implement targeted corrective actions.

Troubleshooting Retention Time Shifts in Liquid Chromatography 

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RECETOX (Research Centre for Toxic Compounds in the Environment) is an independent department of the Faculty of Science of Masaryk University in Brno, which has been established in 1983. RECETOX is focused on the research and education in cross-cutting area of Environment and Health. It addresses interactions among chemicals, environment, and biological systems, including consequences at local, regional, and global levels.

RECETOX - Centrum pro výzkum toxických látek v prostředí

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Waters/Wyatt DAWN™ Multi Angle Light Scattering (MALS) Detector

The world's most advanced light scattering instrument for absolute characterization of proteins, conjugates, macromolecules, and nanoparticles.

<h5>Premier MALS</h5>The DAWN instrument is the premier Multi-Angle static Light Scattering (MALS) detector for absolute characterization of the molar mass and size of macromolecules and nanoparticles in solution. It offers the highest sensitivity, the widest range of molecular weight, size, and concentration, and the largest selection of configurations and optional modules for enhanced capabilities.<h5>Separation First</h5>MALS is most often used in conjunction with a separation system such as Gel Permeation Chromatography (GPC-MALS), Size Exclusion Chromatography (SEC-MALS), or Field-Flow Fractionation (FFF-MALS) to determine distributions of mass, size, and composition, independent of column calibration by reference standards.<h5>Supported by ASTRA ™ &nbsp;Software</h5>ASTRA Software and its built-in analysis modules support the DAWN MALS instrument, providing the most versatile analysis available for online multi-angle and dynamic light scattering measurements.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Waters_DAWN_MALS_HPLC_detektor_konfigurace_d5b83e46b2.jpg" alt="Waters DAWN™ Multi Angle Light Scattering (MALS) Instrument: ASTRA Software" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Waters_DAWN_MALS_HPLC_detektor_konfigurace_d5b83e46b2.jpg 245w," sizes="100vw" width="1500" height="807"><h4>Product description</h4>The DAWN and its companion Optilab ™ &nbsp;dRI detector are the established benchmarks for MALS analysis, cited in thousands of peer-reviewed publications. Multi-angle light scattering detection is indispensable for use with GPC and HPLC-SEC in order to obtain reliable molecular mass distributions and information on molecular conformation, branching ratio, fragments and aggregates.SEC-MALS with a DAWN and Optilab characterizes conformation and branching of synthetic and natural polymers larger than 10 nm in rms radius R g . The addition of a ViscoStar ™&nbsp; differential viscometer creates a GPC triple-detection system that can analyze molecular conformation and size below the R g &nbsp;limit of 10 nm and determine Mark-Houwink Sakurada coefficients.The combination of a UV/Vis absorbance detector with a DAWN instrument and Optilab refractive index detector creates a UV-MALS-RI triple-detection system, for analysis of copolymers and protein conjugates (glycoproteins, PEGylated proteins, surfactant-bound membrane proteins, etc.). With the addition of a WyattQELS ™ &nbsp;DLS module for size determination, protein conformation may be analyzed.<ul><li>Mw &nbsp;from 200 Da to 1000 MDa</li><li>Sensitivity: 10 ng/mL 100 kDa polystyrene in THF, 0.4 µg/mL BSA (66.4 kDa) in PBS</li><li>Rg &nbsp;from 10 to 500 nm, up to 1000 nm with shape-specific models</li><li>Ultra-stable, high-power laser</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Waters_DAWN_MALS_HPLC_detektor_konfigurace_1_98811a1e87.jpg" alt="Waters DAWN™ Multi Angle Light Scattering (MALS) Instrument: Accessories" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Waters_DAWN_MALS_HPLC_detektor_konfigurace_1_98811a1e87.jpg 213w," sizes="100vw" width="1000" height="733">The DAWN may also be used in batch (off-line) mode to characterize the weight-average molar mass, z-average size and second virial coefficient of unfractionated samples.In conjunction with a Calypso ™ &nbsp;CG-MALS system, the DAWN characterizes macromolecular interactions, label-free and immobilization-free: affinity and absolute stoichiometry of self- and hetero-association of simple or complex molecular systems. The Calypso system also automates the determination of second virial coefficients, cross virial coefficients, average molar masses and sizes.<h5>Ultrasonic Cleaning Included</h5>Each DAWN instrument includes an embedded COMET ™ &nbsp;ultrasonic transducer that cleans the flow cell automatically by agitating the fluid and loosening particles from the glass surfaces.<h5>Temperature-Controlled Models</h5><ul><li>Ambient model</li><li>Ultra-High-Temperature (UHT) model, from ambient up to +210 °C</li><li>Standard Peltier heated/cooled (H/C) model, temperature control from -15 °C to +150 °C</li></ul><h4>Specifications</h4><h5>Measurement Capabilities</h5><ul><li>Molar Mass Range: From 200 Da to 1 GDa, depending on dn/dc, sample concentration, and chromatography conditions.</li><li>Molecular Size (Radius of Gyration, Rg): Approximately 10 nm to 500 nm, extendable to 1000 nm with shape-specific models.</li><li>Hydrodynamic Radius (Rh):<ul><li>Flow mode: 0.5 nm to 300 nm (depending on configuration and flow rate).</li><li>Batch mode: 0.5 nm to 1 µm (requires WyattQELS™ DLS module or DynaPro™ NanoStar™ with fiber optic connection).</li></ul></li><li>Sensitivity: Detects as little as 10 ng of 100 kDa polystyrene in THF or 200 ng of BSA in PBS, using a standard 7.8 mm x 300 mm SEC column and no post-column filter.</li></ul><h5>Fluidics and Compatibility</h5><ul><li>Mobile Phase: Compatible with both aqueous and organic solvents.</li><li>Wetted Materials: 316 stainless steel, fused silica or F2 glass, and Kalrez.</li></ul><h5>Optical System and Detectors</h5><ul><li>MALS Detectors: 18 photodiodes with high gain and wide dynamic range for multi-angle light scattering.</li><li>Auxiliary Detectors:<ul><li>Laser monitor for stabilization</li><li>Forward transmission monitor to improve data quality and correct for sample absorption</li></ul></li><li>Dynamic Range: 3,300,000:1</li><li>Optional DLS Detection:<ul><li>Integrated WyattQELS™ module inside the DAWN</li><li>External fiber optic connection with DynaPro NanoStar or Mobius DLS-ELS instruments</li></ul></li></ul><h5>Laser Specifications</h5><ul><li>Wavelength: Standard 658 nm ± 4 nm; optional 785 nm for fluorescent samples</li><li>Power Control: Programmable from 10% to 100%</li></ul><h5>Flow Cell Options</h5><ul><li>Fused Silica: Ideal for solvents with refractive index &lt; 1.50</li><li>F2 Glass: Recommended for solvents with refractive index &gt; 1.50</li></ul><h5>Temperature Control Options</h5><ul><li>Ambient operation</li><li>Heated/Cooled (HC): -15 °C to +150 °C</li><li>Ultra-High Temperature (UHT): Ambient to +210 °C</li></ul><h5>Electronics and Connectivity</h5><ul><li>Analog Inputs: 4 differential inputs, 24-bit resolution, range -10 V to +10 V</li><li>Analog Outputs: 2 outputs from selectable measurement channels, -10 V to +10 V</li><li>I/O Options: Alarm in/out, auto-inject control, and Orbit™ valve integration</li><li>Computer Interface: Ethernet</li><li>Display: 10.1” high-resolution capacitive touchscreen with multi-touch controls</li></ul><h5>Instrument Dimensions</h5><ul><li>Size: 58 cm (L) x 36 cm (W) x 26 cm (H)</li></ul><h4>Other MALS Instruments</h4><ul><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/1115">miniDAWN™</a> &nbsp;- Second only to the DAWN in sensitivity. Incorporates detectors at 3 angles to determine molar masses from 200 Da to 10 MDa and radii from 10 – 50 nm. Ambient only.</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/1116">microDAWN™</a>&nbsp; - The first MALS detector for UHPLC, with interdetector dispersion as low as 1.5 µL. Incorporates detectors at 3 angles to determine molar masses from 200 Da to 20 MDa and radii from 10 – 50 nm. Ambient only.</li><li>ultraDAWN™ &nbsp;- Measures multi-angle light scattering and reports the results – weight-average molecular weight Mw &nbsp;and rms radius Rg &nbsp;– in real time.</li></ul>

Waters/Wyatt miniDAWN™ Multi Angle Light Scattering (MALS) Detector

The Best in Basic Multi-Angle Light Scattering for Absolute Macromolecular Analysis.

<h4>Overview</h4><h5>Molar Mass</h5>The miniDAWN determines absolute molar mass and size to characterize proteins, peptides, small polymers and nanoparticles in solution. Coupled to size exclusion chromatography (SEC or GPC), it eliminates the uncertainty and hassle of column calibration, for true confidence in macromolecular characterization.<h5>Superb Sensitivity</h5>The miniDAWN not only offers superb sensitivity—it further enhances productivity thanks to greatly enhanced field serviceability and easy data analysis with One-Click Mw™ .<h5>Compatible with ASTRA™&nbsp;</h5>The miniDAWN is accompanied by ASTRA, the most versatile software package available for analysis of online multi-angle and dynamic light scattering. ASTRA and the miniDAWN incorporate advanced ease-of-use features that help guarantee excellent measurements with a single click.<h4>Product Description</h4><h5>Molar mass, absolutely</h5>Wyatt's miniDAWN is most often used in conjunction with size exclusion chromatography (SEC-MALS) or field-flow fractionation (FFF-MALS) to determine distributions of molecular weight, size and composition. No need to make assumptions about molecular conformation or ideal column interactions.<h5>Characterize:</h5><ul><li>Proteins, small peptides and oligonucleotides</li><li>Synthetic and natural polymers</li><li>Nanoparticles, virus-like particles and vesicles</li></ul><h5>Measurement Range:</h5><ul><li>MW from 200 Da to 10 MDa</li><li>rg &nbsp;from 10 to 50 nm, up to 150 nm with shape-specific models</li><li>sensitivity down to 25 ng of 100 kDa polystyrene in THF, injected on a standard GPC column</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Waters_Mini_DAWN_urcuje_molekulovou_hmotnost_nezavisle_na_kalibraci_kolony_Zde_MALS_ukazuje_ze_nejdrive_eluujici_molekula_nema_nejvyssi_molarni_hmotnost_509e5530ea.jpg" alt="Waters: The miniDAWN determines molecular weight independently of column calibration. Here MALS shows that the earliest-eluting molecule does not have the highest molar mass." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Waters_Mini_DAWN_urcuje_molekulovou_hmotnost_nezavisle_na_kalibraci_kolony_Zde_MALS_ukazuje_ze_nejdrive_eluujici_molekula_nema_nejvyssi_molarni_hmotnost_509e5530ea.jpg 245w," sizes="100vw" width="820" height="438">The miniDAWN's performance is exceeded only by the DAWN™ which covers a wider range of size and molecular weight, with even better sensitivity and additional optional modules.<h5>Ultrasonic Cleaning Included</h5>Each miniDAWN includes an embedded COMET™ ultrasonic transducer that cleans the flow cell automatically by agitating the fluid and loosening particles from the glass surfaces.<h5>Modularity = Productivity</h5>The miniDAWN incorporates a fully modular design. Each module can be tested independently by the software to verify that it is functioning correctly. This imparts nearly complete field serviceability, since malfunctioning modules can be replaced and validated on-site by service engineers with no further calibration or alignment.The miniDAWN is also field-upgradeable: the embedded WyattQELS™ DLS Module for measuring hydrodynamic radii from 0.5 to 50 nm can be installed on-site as well as in new units shipped from the factory.<h5>Not just SEC-MALS...</h5>Wyatt's miniDAWN may be used in batch (off-line) mode or in conjunction with a Calypso™ CG-MALS system for characterization of average solution properties as well as macromolecular interaction properties including protein-protein binding affinity and complex stoichiometry.<h5>Simplicity personified</h5>With miniDAWN and ASTRA™, SEC-MALS became a whole lot easier. Sample-specific methods are set up in three short steps with ASTRA's Method Wizard, and new capabilities for automatic data processing mean that it takes just one click from your sample to a full report of the molecular weight and size results.The miniDAWN's System Ready monitor will even let you know when the system is fully equilibrated with low baseline noise, ready to run.<h4>Specifications</h4><h5>Measurement Capabilities</h5><ul><li>Molar Mass Range: 200 Da to 10 MDa for proteins; up to 1 MDa for linear polymers (depending on dn/dc, sample concentration, and chromatography conditions).</li><li>Molecular Size (Radius of Gyration, Rg): Approximately 10 nm to 50 nm, extendable up to 150 nm with shape-specific modeling.</li><li>Hydrodynamic Radius (Rh):<ul><li>Flow mode: 0.5 nm to 50 nm (optimal at flow rates ≤ 0.3 mL/min)</li><li>Batch mode: 0.5 nm to 1 µm (requires WyattQELS™ module or DynaPro™ NanoStar™ with fiber optic connection)</li></ul></li><li>Sensitivity: Detects as little as 25 ng of 100 kDa polystyrene in THF or 500 ng of BSA in PBS using a standard 7.8 mm x 300 mm SEC column with no post-column filter.</li></ul><h5>Fluidics and Compatibility</h5><ul><li>Mobile Phase Compatibility: Compatible with both aqueous and organic solvents.</li><li>Wetted Materials: 316 stainless steel, fused silica, and Kalrez.</li></ul><h5>Optical System and Detectors</h5><ul><li>MALS Detectors: Three high-gain, high dynamic range photodiodes at fixed angles.</li><li>Auxiliary Detectors:<ul><li>Laser monitor for stability control</li><li>Forward transmission monitor for absorbing samples and data quality evaluation</li></ul></li><li>Dynamic Range: 3,300,000:1</li><li>Optional DLS Detection:<ul><li>Integrated WyattQELS™ module within the miniDAWN chassis</li><li>External fiber optic connection from DynaPro™ NanoStar or Mobius™ DLS-ELS instruments</li></ul></li></ul><h5>Laser Specifications</h5><ul><li>Wavelength: 658 nm ± 4 nm</li><li>Power Control: Programmable from 10% to 100%</li></ul><h5>Temperature Control</h5><ul><li>Sample Temperature: Ambient</li></ul><h5>Electronics and Connectivity</h5><ul><li>Analog Inputs: 2 differential inputs, 24-bit resolution, ±10 V range</li><li>Analog Outputs: 1 output from a selectable measurement channel, ±10 V range</li><li>I/O Ports: Alarm in/out, auto-inject control, Orbit™ recycle valve support</li><li>Computer Interface: Ethernet</li><li>Data Rate: Up to 36.6 Hz</li></ul><h5>User Interface and Display</h5><ul><li>Front Panel: 7” (178 mm) high-resolution multi-touch display for real-time signal viewing, diagnostics, and settings</li></ul><h5>Instrument Dimensions</h5><ul><li>Size: 58 cm (L) x 36 cm (W) x 18 cm (H)</li></ul><h4>Other MALS Instruments</h4><ul><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/1114">DAWN™</a> - The most sensitive MALS detector available, anywhere. Incorporates detectors at 18 angles to determine molar masses from 200 Da to 1 GDa and radii from 10 – 500 nm.<ul><li>Standard option: ambient temperature</li><li>Heated/cooled option: -15 °C to +150 °C</li><li>High-temperature option: ambient to +210 °C</li><li>The DAWN offers special options to handle fluorescent samples: fluorescence-blocking filters and an infrared, 785 nm laser.</li></ul></li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/1116">microDAWN™</a> - The first MALS detector for UHPLC, with interdetector dispersion as low as 1.5 µL. Incorporates detectors at 3 angles to determine molar masses from 200 Da to 20 MDa and radii from 10 – 50 nm. Ambient only.</li><li>ultraDAWN™ - Measures multi-angle light scattering and reports the results – weight-average molecular weight Mw &nbsp;and rms radius Rg &nbsp;– in real time.</li></ul>

Waters/Wyatt microDAWN™ Multi Angle Light Scattering (MALS) Detector

The microDAWN can be coupled to any UHPLC-SEC system to determine absolute molecular weights and sizes of polymers, peptides, or proteins directly, without resorting to column calibration or reference standards.

<h4>Overview</h4><h5>UHPLC-SEC System</h5>The microDAWN can be coupled to any UHPLC-SEC system to determine absolute molecular weights and sizes of polymers, peptides, or proteins directly, without resorting to column calibration or reference standards. The microDAWN produces minimal band broadening in order to maintain the narrow peaks typical of UHPLC, while meeting or exceeding the sensitivity of the miniDAWN™.<h4>Product Description</h4>The microDAWN MALS detector performs absolute characterization of macromolecules eluting from UHPLC, determining molar mass and size independently of retention time and molecular reference standards. This instrument offers superb sensitivity over a wide range of molar mass, size and concentrations. In most respects the microDAWN is similar to the well-established miniDAWN™, a workhorse MALS instrument used in hundreds of labs around the world for characterizing proteins and other molecules smaller than 50 nm in radius.Distinctly from the miniDAWN, the microDAWN is uniquely suitable for use in conjunction with UHPLC Size Exclusion Chromatography (SEC-MALS) thanks to its small interdetector dispersion. In some cases it may be used with ion-exchange or other types of chromatography. Regardless of the specifics, the microDAWN produces minimal band broadening in order to maintain the narrow peaks typical of UHPLC.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Waters_micro_DAWN_MALS_HPLC_detektor_konfigurace_1_4e888650cf.jpg" alt="Waters microDAWN™ Multi Angle Light Scattering (MALS) Instrument: Experimental setup" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Waters_micro_DAWN_MALS_HPLC_detektor_konfigurace_1_4e888650cf.jpg 229w," sizes="100vw" width="894" height="609"><ul><li>Mw&nbsp; from 200 Da to 10 MDa</li><li>Sensitivity: 1.0 µg/mL BSA (66.4 kDa) in PBS; 50 ng/mL 100 kDa polystyrene in THF.</li><li>Rg &nbsp;from 10 to 50 nm</li><li>Ultra-stable laser</li></ul>The microDAWN and its companion microOptilab™ Refractive Index Detector interface to most standard UHPLC systems. As these detectors are based on the advanced technology of Wyatt's miniDAWN and Optilab™, respectively, users may be confident in the underlying capabilities cited in thousands of peer-reviewed publications.<h5>Ultrasonic Cleaning Included</h5>Each microDAWN includes a COMET™ ultrasonic transducer that cleans MALS flow cells automatically by agitating the fluid and loosening particles from the glass surfaces.<h4>Specifications</h4><h5>Measurement Capabilities</h5><ul><li>Molar Mass Range: From 200 Da to 10 MDa for proteins; up to 1 MDa for linear polymers (Typical, depending on dn/dc, sample concentration, and chromatography conditions)</li><li>Molecular or Particle Size (Radius of Gyration, Rg): 10 nm to 50 nm, extendable up to 150 nm with shape-specific modeling</li><li>Hydrodynamic Radius (Rh):<ul><li>Flow mode: 0.5 nm to 30 nm</li><li>Batch mode: 0.5 nm to 1 µm (Requires WyattQELS™ DLS module or DynaPro™ NanoStar™ with fiber optic connection)</li></ul></li><li>Sensitivity: Detects as little as 3.5 ng of 100 kDa polystyrene in THF or 70 ng of BSA in PBS, assuming use of a 15 cm UHPLC-SEC column with no post-column filter</li></ul><h5>Optical System and Detectors</h5><ul><li>MALS Detectors: Three high-gain photodiodes with broad dynamic range for multi-angle light scattering</li><li>Dynamic Range: 3,300,000:1</li><li>Auxiliary Detectors:<ul><li>Laser monitor for stabilization feedback</li><li>Forward transmission monitor for absorbing samples and data quality assessment</li></ul></li><li>Optional DLS Detection:<ul><li>Integrated WyattQELS™ module within the microDAWN chassis</li><li>External DLS connection via fiber optic from DynaPro™ NanoStar or Mobius™ DLS-ELS instruments</li></ul></li></ul><h5>Laser Specifications</h5><ul><li>Wavelength: 658 nm ± 4 nm</li><li>Power Control: Programmable from 10% to 100%</li></ul><h5>Sample Temperature and Flow Characteristics</h5><ul><li>Sample Temperature: Ambient</li><li>Interdetector Band Broadening:<ul><li>Upstream detector to microDAWN: &lt; 1.5 µL</li><li>Upstream to downstream detector: &lt; 1.6 µL</li></ul></li></ul><h5>Material Compatibility</h5><ul><li>Wetted Materials: 316 stainless steel, fused silica, PEEK, PTFE, and MP35N (iron-free alloy)</li></ul><h5>Electronics and Connectivity</h5><ul><li>Analog Inputs: 2 differential inputs, 24-bit resolution, ±10 V input range</li><li>Analog Outputs: 1 output from a user-selectable measurement channel, ±10 V range</li><li>I/O Ports: Alarm in/out, auto-inject control, Orbit™ valve integration</li><li>Computer Interface: Ethernet</li><li>Data Transmission Rate: Up to 73 Hz</li></ul><h5>User Interface</h5><ul><li>Display: 7” (178 mm) high-resolution multi-touch screen for signal monitoring, instrument settings, and diagnostics</li></ul><h5>Instrument Dimensions</h5><ul><li>Size: 58 cm (L) x 36 cm (W) x 18 cm (H)</li></ul><h4>Other MALS Instruments</h4><ul><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/1114">DAWN™</a> - The most sensitive MALS detector available, anywhere. Incorporates detectors at 18 angles to determine molar masses from 200 Da to 1 GDa and radii from 10 – 500 nm.<ul><li>Standard option: ambient temperature</li><li>Heated/cooled option: -15 °C to +150 °C</li><li>High-temperature option: ambient to +210 °C</li><li>The DAWN offers special options to handle fluorescent samples: fluorescence-blocking filters and an infrared, 785 nm laser.</li></ul></li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/1115">miniDAWN™</a> - Second only to the DAWN in sensitivity. Incorporates detectors at 3 angles to determine molar masses from 200 Da to 10 MDa and radii from 10 – 50 nm. Ambient only.</li><li>ultraDAWN™ - Measures multi-angle light scattering and reports the results – weight-average molecular weight Mw &nbsp;and rms radius Rg &nbsp;– in real time.</li></ul>

Products from category MALS detectors from Waters - page 1

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