Home » Corporate, Dynamic Light Scattering, Size Exclusion Chromatography, Viscotek

Sizing up the situation

7 March 2011 One Comment

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As someone who is new to the blog, I would like to introduce myself. My name is Mark Pothecary and I am product technical specialist for the separation sciences product line at Malvern Instruments. My background is biochemistry and here at Malvern I develop nanoparticle characterization and size-exclusion chromatography (SEC) applications – also referred to as Gel Permeation Chromatography (GPC). You may already be familiar with my webinars about advanced multi-detector SEC and technical applications.

Updating busy scientists

In February I had the opportunity to speak at a series of seminars in Australia which went under the title ‘Molecules to nanoparticles – selecting the optimum characterization technique for proteins and polymers’. These were intended as a quick and convenient update for busy scientists (aren’t we all?) on optimizing characterization techniques for proteins and polymers.

During the event we discussed the similarities and differences between dynamic and static light scattering (DLS/SLS), size-exclusion chromatography and multi-detector SEC with an overview of the theories and technologies behind them.

Viscotek GPC/SEC

One of the advances of interest to me specifically is Malvern’s Viscotek GPC/SEC range, which enables multi-detector analytical GPC/SEC through a triple or tetra detector array, and provides complementary sample data including sample concentration, molecular weight, size, intrinsic viscosity (which is a measure of molecular density).

The Viscotek TDAmax uses SLS to measure molecular weight. SLS measures the intensity of scattered light to obtain the average molecular weight of a protein or polymer, without requiring calibration to the volume of the GPC elution.

This technique is complementary with DLS, which is performed by the Zetasizer range of instruments. DLS determines particle size in nanometers by measuring diffusion rate. Samples analyzed can range in size from less than 1 nanometer up to several microns.

Knowledge is power!

Other discussions at the seminar covered protein conjugates, drug delivery, and aggregation all of which were useful, informative and illustrated the sheer depth of knowledge evident in this field.

Let me know if you have any questions or comments on any of these fascinating research areas.