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Molecular weight

Absolute molecular weight determination and measurement of molecular weight distribution.

Dynamic Light Scattering, Electrophoretic light scattering, Malvern Panalytical Events, Meet the Experts, Molecular size, Molecular weight, Particle size, Protein Aggregation, Protein Mobility, Static Light Scattering, Tech Talk, Zeta potential, Zetasizer »

[12 Oct 2018 | ]

Join us for the next User group meeting!
User Group Meeting Announcement 19 Oct 2018 1pm-4pm EDT

We are pleased to announce the first virtual Zetasizer User Meeting ZUM-1! This initiative is an effort to foster the diffusion of knowledge and experience between our support group and those researchers that regularly evaluate light scattering data from the Zetasizer. The Zetasizer Users Community is invited to present and share data with specific questions. Get live feedback from our panel of experts.
The meeting will be live-streamed via Webex and is limited to 3.0 hours. …

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Gel permeation chromatography, Molecular weight, OMNISEC, Size Exclusion Chromatography »

[19 Sep 2018 | ]

Determining which gel permeation/size exclusion chromatography (GPC/SEC) system is best for your needs can be a daunting task. Even after you’ve decided to include a light scattering detector to obtain absolute molecular weight data you’re still left to choose between two options: a multi-angle light scattering (MALS) detector or a right angle and low angle light scattering detector (RALS/LALS). Both light scattering configurations will provide the absolute molecular weight of a sample but utilize different approaches toward that common goal. Fortunately, Malvern Panalytical offers both; the modular SEC-MALS 20 unit …

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Gel permeation chromatography, Molecular structure, Molecular weight, OMNISEC, Size Exclusion Chromatography »

[12 Sep 2018 | ]

When thinking about a reason to purchase a particular piece of scientific equipment, you want to know not only that you are getting the best piece of kit, but also that you’ll be maximizing the return on your investment.  Manufacturers like Malvern Panalytical can add value to their products in a variety of ways, and one is the support and materials you’ll get to help you make the most of your purchase.  In this blog, I want to tell you about the additional benefits and added value that you’ll receive …

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Gel permeation chromatography, Molecular structure, Molecular weight, OMNISEC, Size Exclusion Chromatography, Tech Talk »

[22 Aug 2018 | ]

The most common detector in any GPC/SEC instrument is a refractive index (RI) detector.  There are multiple reasons for this, but the most important is because the difference in refractive index between that of a sample solution and that of the same solvent without a sample is directly proportional to the concentration of the sample.  This is why RI detectors are referred to as concentration detectors.  (It should be noted that UV-Vis detectors are also concentration detectors, but require the sample has a chromophore and absorbs light at a detectable …

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Gel permeation chromatography, Molecular weight, OMNISEC, Size Exclusion Chromatography, Tech Talk »

[12 Jul 2018 | ]

To many people, obtaining molecular weight information from GPC/SEC analysis involves a lengthy calibration process.  A series of standards of known molecular weight are analyzed and a calibration curve based on the standards’ retention volume is generated.  This can be a tedious procedure, and the result is only relative molecular weight data.
The inclusion of a light scattering detector in a GPC/SEC system eliminates the need to run a series of standards to generate a calibration curve, as the sample’s molecular weight is measured directly by the light scattering detector.  This …

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Corporate, Dynamic Light Scattering, Electrophoretic light scattering, Molecular size, Molecular weight, Particle concentration, Particle size, Zeta potential, Zetasizer »

[23 May 2018 | ]

Where is the Zetasizer used?
 
For around two decades, the Zetasizer range has been the de facto standard for performing dynamic light scattering (DLS) measurements on a wide range of particles and materials.
Today’s launch of the Zetasizer Pro and Zetasizer Ultra – which took place earlier today on May 23rd, 2018 – provides a good reason to summarize the key application areas for light scattering technology: both dynamic and electrophoretic! Where are these Zetasizers used? Where can we find them, in the real world?
Below is a list of key application focus areas:

Bioscience and biopharmaceuticals: …

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Français, Gel permeation chromatography, Malvern Panalytical Events, Meet the Experts, Molecular size, Molecular structure, Molecular weight, OMNISEC »

[9 May 2018 | ]

Atelier dans notre agence de Lyon mardi 12 juin

Journée sur la chromatographie d’exclusion de taille pour les protéines (ou de perméation de gel pour les polymères) dans notre agence de Lyon.
Vous seront présentés différents systèmes de détection UV, réfractomètre, diffusion de lumière, viscosité intrinsèque, MALS, connectables sur tous les types de colonnes, ainsi que sur des systèmes UHPLC.
Nous vous accueillerons à partir de 8h30 et les présentations commenceront à 9h00. Après le déjeuner (offert), se tiendront des sessions d’essais clients jusqu’à 16h30, date de la fin de la journée.
La participation à …

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Dynamic Light Scattering, Gel permeation chromatography, Kinexus, Laser Diffraction, Malvern Panalytical Events, Meet the Experts, Molecular weight, Nanoparticle Tracking Analysis, Nanosight, OMNISEC, Particle concentration, Particle size, Rheology, Rheometry, Tech Talk, Viscotek, Zeta potential, Zetasizer »

[30 Jan 2018 | ]

We will be attending Pittcon 2018 in Orlando, Florida Feb 26th – Mar 1st and once again we are pleased to feature a number of our recognized characterization experts who will be presenting a variety of short courses throughout the week.
Time is running out, so don’t miss out on the early bird deadline for discounted admission which ends on February 5th.
Below is a listing of our available short course offerings.
We look forward to seeing you in Orlando at one of our short courses and our Booths #2118 & #2119.
Monday, February 26th
Fundamentals of Particle …

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Gel permeation chromatography, Molecular weight, OMNISEC »

[23 Jan 2018 | ]

Examples of Polystyrene, Polyvinylchloride and Polycarbonate measurements
When Waters Corp. released the ACQUITY Advanced Polymer Chromatography (APCTM) system for polymer analysis it brought the unsurpassed resolution of UPLC separations to the polymer market. The system allows resolution between polymer fractions not previously seen with the added advantage of low sample use, low solvent use, and significantly quicker analysis. This was, of course, a fantastic step forward but retained the need for column calibration to give relative molecular weight distributions. How accurate these values depend on the chemical and structural similarities between …

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Dynamic Light Scattering, Molecular size, Molecular weight, Static Light Scattering, Tech Talk, Zetasizer »

[2 Nov 2017 | ]

Molecular weight measurements with the Zetasizer software?
First a few words of caution: molecular weight or Mw measurements in general are not easy, require time, good sample preparation skills as well as patience. If you are new to the Malvern Zetasizer it might be best to familiarize yourself first with the rapid, user-friendly, and quite forgiving technique of dynamic light scattering (DLS). {{If you are experienced and want to skip to a Brainshark narrated screen recording of the steps, best viewed in Chrome, go ahead to https://www.brainshark.com/malvern/sls-with-zetasizer }}.
OK, with that out …

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Dynamic Light Scattering, Molecular size, Molecular weight, Size Exclusion Chromatography, Static Light Scattering, Tech Talk, Viscotek, Zetasizer »

[23 Oct 2017 | ]

The term polydispersity (or more recently dispersity without the poly, as per IUPAC recommendation) is used to describe the degree of “non-uniformity” of a distribution.  In the field of molecular/nanoparticular characterization, there are in principle two different definitions of polydispersity, depending on the underlying property of interest.
In Gel Permeation Chromatography (GPC) and Size Exclusion Chromatography (SEC), we are interested in the molecular weight of the sample. The distribution obtained from GPC/SEC is typically a molecular weight distribution describing how much material there is present of the various molecular weight “slices.”  …

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Differential Scanning Calorimetry, Dynamic Light Scattering, Meet the Experts, MicroCal, Molecular size, Molecular weight, OMNISEC, Particle concentration, Protein Aggregation, Size Exclusion Chromatography, Taylor Dispersion Analysis, Zetasizer »

[18 Jul 2017 | ]

Monoclonal Antibodies – or mAbs for short

Since many of these mAbs require refrigeration we had used dynamic light scattering (with a Zetasizer) to show the formation of aggregates after freeze-thaw cycles (for details see application note “Effect of storage conditions on Immunoglobulin“). These could be seen both in the increased polydispersity index (PDI) and the appearance of a large-size aggregate peak in the intensity size distribution as shown to the right. The area under the peak gives an indication of the presence of the large aggregates but is not suited for …

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Differential Scanning Calorimetry, Isothermal Titration Calorimetry, MicroCal, Microcalorimetry, Molecular weight, Tech Talk »

[23 May 2017 | ]

A professional and personal view
If your newsfeed from scientific and mainstream media sources is anything like mine, you have seen numerous articles and blogs about the ‘reproducibility crisis’ in the life sciences.
Well-established cornerstones of scientific inquiry and research are the publication of findings in peer-reviewed journals, along with the opportunity for others to reproduce and verify published data.  This advancement and consolidation of knowledge leads to further understanding on how biological systems work, and provides the basis for the discovery and development of new drugs which benefit all of us.
However, there …

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Archimedes, Chemical identification, Label-free analysis, Malvern Panalytical Events, MicroCal, Microcalorimetry, Molecular size, Molecular structure, Molecular weight, Morphologi, Nanosight, Particle concentration, Particle shape, Particle size, Protein Aggregation, Protein Mobility, Viscosizer TD, Zeta potential, Zetasizer »

[16 May 2017 | ]

With Pre-Conference Workshop on Biophysical Characterization and Particle Analysis
 

Date: July 17th – 20th.
We at Malvern know that protein stability is important in numerous disciplines, ranging from basic and medical biochemistry to pharmaceutical sciences. However, it is rare that researchers from all the relevant areas can join to discuss the critical issues in the field. The 2017 Colorado Protein Stability Conference provides a unique forum for this exchange of information. The topics to be covered include protein folding, dynamics and thermodynamic stability; amyloidosis and protein aggregation; and stability, formulation, analysis and processing …

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Gel permeation chromatography, Molecular weight, OMNISEC, Size Exclusion Chromatography, Tech Talk »

[23 Feb 2017 | ]

Recently, I’ve presented a new webinar focusing on the protein characterization using the OMNISEC, the highest quality Gel Permeation Chromatography (GPC) / Size Exclusion Chromatography (SEC) system for the measurement of absolute molecular weight, molecular size, intrinsic viscosity, branching and other parameters. Thank you to all participants for your interest and attention during the webinar.
In this webinar, I highlighted the key features and benefits of the OMNISEC system. How to run samples and analyze data and how to access repeatability of multiple sample measurements.

As usual, after the live section of …

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Meet the Experts, Molecular weight, OMNISEC, Particle size, Tech Talk, Zeta potential, Zetasizer »

[30 Jan 2017 | ]

Malvern Instruments takes part at the 8th International Symposium on the Separation and Characterization of Natural and Synthetic Macromolecules (SCM-8) at Rhone Events & Congrescenter. The main interest of the conference is the separation and characterization of large molecules. The target audience includes specialists from analytical chemistry, polymer science, and life-science communities.
Malvern is a sponsor of the conference so keep an eye out for us at our booth. In addition, I will give a talk on Thursday February, 2nd about ‘Combining Multi-Detector GPC Measurements with Ultra-High Performance GPC Separations’. The …

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Gel permeation chromatography, Malvern Panalytical Events, Molecular size, Molecular weight, OMNISEC, Size Exclusion Chromatography, Viscotek »

[8 Dec 2016 | ]

Version Française
The French symposium of the French Group of Studies and Applications of Polymers (GFP) is the major French congress of polymers.
The 45th edition took place recently in Marseille under the bold architecture of the Villa Méditerranée, designed by Stefano Boeri, a committed actor of the Italian political and cultural scene.

During this conference, we presented the benefits of Viscotek SEC MALS 20.
The SEC-MALS 20 multi-angle light scattering detector  can be used on all GPC / SEC systems and especially Malvern’s latest OMNISEC range. The 20 signals of the SEC-MALS detectors connected …

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Français, Gel permeation chromatography, Malvern Panalytical Events, Molecular size, Molecular weight, OMNISEC, Size Exclusion Chromatography, Viscotek »

[8 Dec 2016 | ]

English version
Le colloque national du Groupe Français d’études et d’applications des Polymères (GFP) est le congrès français majeur des polymères.
La 45ème édition s’est déroulée récemment à Marseille sous l’architecture audacieuse de la Villa Méditerranée, conçue par Stefano Boeri, acteur engagé de la scène politique et culturelle italienne.

Durant ce congrès, nous avons présenté les avantages du Viscotek SEC MALS 20.
Le détecteur de diffusion de lumière multi-angle Viscotek SEC-MALS 20 peut être utilisé sur tous les systèmes de GPC/SEC et notamment sur le dernier OMNISEC de la gamme Malvern. Les signaux des 20 détecteurs du SEC-MALS …

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Customer experience, Dynamic Light Scattering, Electrophoretic light scattering, Molecular size, Molecular weight, Particle size, Zeta potential, Zetasizer »

[20 Oct 2016 | ]

How can I save paper and print a Zetasizer report as a PDF?
 
Why print?
The Zetasizer software includes several popular report options. The most frequently used of these is probably the Intensity PSD (M), which gives a compact overview of the results. It lists the z-average and up to three peaks by intensity with their respective mean size, the area under the peak in % intensity and the standard deviation of the peak. In addition, several relevant sample identifiers and measurement conditions, like the sample name,  file name, refractive index of …

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Gel permeation chromatography, Malvern Panalytical Events, Meet the Experts, Molecular weight, OMNISEC, Size Exclusion Chromatography, Tech Talk, Viscotek »

[13 Sep 2016 | ]

Together with Sysmex, our distributor in Benelux, we are proud to be Gold Sponsors of the International Symposium on GPC/SEC and Related Techniques, taking place from 26-29th September in Amsterdam.
One of our technical experts, John Stenson, is looking forward to presenting some exciting new data in his talk “Combining multi-detector GPC measurements with ultra-high pressure GPC separations” at 3:30 pm on Wednesday 28th September, and says:
“This presentation will discuss the issues related to dispersion and how these can be minimized. We will then show the first high quality data from a combined multi-detector/ UPLC™ …

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