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Molecular size

Measure absolute molecular size without calibration.

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.
Our launch of the Zetasizer Pro and Zetasizer Ultra – taking place 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: simple purity and stability …

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Customer experience, Dynamic Light Scattering, Molecular size, Particle size, Tech Talk, Zetasizer »

[15 May 2018 | ]

The peaks in your distribution are out of order?
We recently received an email about the order of peaks in the Zetasizer software:
For data evaluation, is it possible to rearrange the NNLS results by order of particle size populations?”
How the peaks are shown (by area)

Size measurement results are typically viewed in the Intensity PSD (M) tab. This is part of the standard Size and Summary workspaces.  When a record contains more than one peak, these results will be tabulated in the table above the intensity size distribution. The default ordering in …

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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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Differential Scanning Calorimetry, Dynamic Light Scattering, MicroCal, Molecular size, Molecular structure, Particle size, Protein Aggregation, Tech Talk, Zetasizer »

[16 Nov 2017 | ]

Measuring aggregation temperature using the Zetasizer

In dynamic light scattering (DLS), the hydrodynamic size and size distribution of particles in solution can be obtained.  It may be of interest to examine this measurement as a function of time and temperature, or as a ‘trend’, as it is called in the Malvern Zetasizer software.  For biological protein samples, this temperature trend is particularly interesting: although at low temperatures a protein may be stable and show repeatable size (and scattering intensity) measurements, typically at some elevated temperature (Tagg), protein molecules will show a tendency …

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

[25 May 2017 | ]

A challenge to all new Zetasizers!
 
The Zetasizer is so simple to use that the majority of Zetasizer (user)s just “dive in” and find out how to operate the system.
By design it is (almost) indestructable, so what can go wrong? Not much – nevertheless, you might be able to get even more use and benefit from your system with a little preparation.
 
Free eLearning video – really!
If you are relatively new to the Zetasizer then take a look at our free eLearning introductory course. It was meant as a teaser for the …

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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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Customer experience, Dynamic Light Scattering, Molecular size, Particle size, Zeta potential, Zetasizer »

[4 May 2017 | ]

3 stumbling blocks for Report Designer (Zetasizer) – the rule of two
The three most common holdups encountered in the report designer feature are listed here.
Not everyone delves into the depth of the Zetasizer software, but of those who do want to take advantage of the report customization features in the ‘report designer’ nearly everyone runs into at least one of these three common mistakes:

1. Folder locations – there are two!
The Zetasizer software is typically installed in a (hidden) Windows directory like  C:\Program Files\Malvern Instruments\Zetasizer Software and that’s good. However, if …

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Dynamic Light Scattering, Molecular size, Particle concentration, Particle size, Protein Aggregation, Tech Talk, Zetasizer »

[7 Mar 2017 | ]

How can I use DLS for sample xyz?
What sample concentration / refractive index is needed for reliable DLS size measurements?

Has it been done before?
In Dynamic Light Scattering (DLS) intensity fluctuations in the sample are analyzed to obtain size information on the sample. The technique is applicable to a wide size range from sub-nanometer up to a few microns. In order to obtain a meaningful result, a minimum scattering signal strength must be present. Malvern’s Zetasizer Nano software contains a calculator to help estimate the required minimum concentration.
If anyone else has …

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Binding affinity and Kd, Differential Scanning Calorimetry, Dynamic Light Scattering, Français, Gel permeation chromatography, Image Analysis, Isothermal Titration Calorimetry, Laser Diffraction, Meet the Experts, Molecular size, Nanoparticle Tracking Analysis, Particle concentration, Particle size, Rheology, Rheometry, Size Exclusion Chromatography, Static Light Scattering, Zeta potential »

[21 Feb 2017 | ]

Afin de vous apporter un support concret pour utiliser votre système de façon optimale, finaliser vos bonnes pratiques de laboratoire et répondre à vos besoins spécifiques, Malvern organise des formations sur site ou en sessions dans nos 3 agences françaises (Orsay, Lyon et Toulouse).
Voici les dates de toutes les sessions programmées pour 2017 :
CARACTERISATION DES PARTICULES PAR DIFFRACTION LASER
Objectifs : Perfectionner les méthodes de caractérisation des particules en voie sèche et liquide, définir les bonnes pratiques de laboratoire et s’adapter aux besoins spécifiques de chaque installation. Comprendre le principe physique …

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Dynamic Light Scattering, Molecular size, Molecular structure, Particle size, Tech Talk, Zetasizer »

[27 Dec 2016 | ]

How to measure it with DLS?
What virus concentration is needed for reliable DLS size measurements?
 
What is a virus?
In cell biology, a virus is a self assembly of organic molecules (mainly proteins) in the size range 20 nm – 300 nm (diameter). Viruses hold great interest for human gene therapy researchers, and the AAV-2  virus shown to the left is an example.
How to size a virus in solution?

One of the techniques available to size viruses (as well as other biological nanoparticles) is Dynamic Light Scattering (DLS), where intensity fluctuations in a small …

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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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Dynamic Light Scattering, Molecular size, Protein Aggregation, Tech Talk, Zetasizer »

[1 Nov 2016 | ]

α-synuclein promotes vesicle assembly – when size can support theory
 

What is a vesicle?
In cell biology, a vesicle is an (often spherical) assembly of amphiphilic molecules (usually proteins and phospholipids), and is typically sized between 30 nm – 100 nm in diameter. Vesicles are often classified by the type of interaction they are involved with. For extracellular vesicles (or exosomes), this is usually intercellular signal transmission. A particular example of exosomes is synaptic vesicles, which transmit signals between neurons (average size: 40 nm).
In a paper entitled “Structural basis of synaptic vesicle assembly promoted …

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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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Dynamic Light Scattering, Molecular size, Particle size, Tech Talk, Zetasizer »

[16 Aug 2016 | ]

Why are my particles measuring too small?
The technique of  Dynamic Light Scattering (DLS) has become quite standard in many biophysical characterization labs, often alongside common tools like UV-Vis, SEC, AUC, Fluorescence, NMR, AFM, SAXS, or Mass Spec.  As DLS systems (like the Malvern Zetasizer Nano) have become ever easier to use we see an increasing range of applications and research. By observing and analyzing intensity fluctuations in a sample, we can find the diffusion coefficient and, with known viscosity, the corresponding size. Inevitably, at some point the size measured will not …

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Dynamic Light Scattering, Molecular size, Particle size, Tech Talk, Zetasizer »

[21 Jul 2016 | ]

“What is dynamic light scattering?” Find out in less than 5 minutes!
Although we’ve gone into deeper detail in previous posts , every once in a while it’s nice to recap on the basics. A few years ago, our presentation “Dynamic Light Scattering Primer” was among the top three recordings in the Malvern charts for months in a row. Over the last decade, DLS has  become one of the de facto nanoparticle characterization standard methods. And it’s used not only for nanoparticles, but also for molecules, proteins, drug delivery particles, liposomes, virus like particles, …

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Malvern Panalytical Events, Meet the Experts, Molecular size, Zetasizer »

[23 Feb 2016 | ]

It’s not unusual to see a Malvern Zetasizer in a University laboratory. In fact, there are so many educational institutions taking advantage of the quick and reliable information dynamic light scattering (as well as electrophoretic light scattering) can provide, that it is more likely that there already is a system somewhere on your campus than not.  We are delighted that light scattering plays an integral role in so many academic institutes around the world!  If youre wondering whether there is a system on your campus, just contact our Helpdesk, who …

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Dynamic Light Scattering, Molecular size, Particle size, Tech Talk, Zetasizer »

[26 Jan 2016 | ]

In the Malvern Zetasizer software we measure the intensity auto-correlation function. This is obtained from correlating the scattering intensity with itself. The resulting intensity auto-correlation function is often denoted by the symbol G2(τ) in its normalized form. For Gaussian scattering, there is a relationship between the intensity and the field correlation function, known as the Siegert relation.
If we denote the normalized field correlation function as G1(τ) then under ideal conditions:
G2(τ) = 1 + G1(τ)^2  (In real measurements there would also be a baseline and a signal-to-noise ratio)
Within the Malvern software, …

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