Protein electrophoretic mobility measurements for protein characterization.
Electrophoretic mobility measurements from proteins: How to protect proteins in an electric field
What is the protein mobility mode?
When applying an electric field to a sample containing protein molecules, there are a few considerations to take into account to avoid “over-stressing” delicate biomolecules. The force a charged object experiences in an electric field is proportional to its charge times the electric field. Therefore the electric field strength (defined by the applied voltage divided by the distance between the electrodes, in V/cm) is more relevant than the absolute value of the applied …
Electrophoretic light scattering, Nanosight, Protein Mobility, Tech Talk, Zeta potential, Zetasizer »
How to perform zeta potential measurement with the diffusion barrier method?
The diffusion barrier method is particularly suitable for low sample volumes and high ionic strength buffers. A “plug” of the sample is carefully injected into the folded capillary cells which is filled with just the buffer (The buffer has to be the same buffer that the protein is prepared in, same conductivity, same pH, same additives, in order to match the sample and the diffusion barrier as closely as possible). In this setup, primarily the zeta potential is of interest, however …Read the full story »
How can the zeta deviation be larger than the mean?
We recently received a phone call from a customer asking about their zeta potential results: When they are measuring electrophoretic light scattering, the zeta potential value for their sample is 15.4mV and the Standard Deviation is 24mV. Why is the Standard Deviation larger than the actual mean Zeta potential ?
To understand this better let’s first look at the concept of M3-PALS . M3 stands for mixed mode measurement: while traditional electrophoretic measurements are performed by measurement of particles at the stationary layer (= a …
Molecular size, Molecular structure, Molecular weight, Particle shape, Protein Mobility, Zetasizer »
The Zetasizer has some optional advanced protein features that you may not be aware of:
DLS Debye Plot: a dynamic Debye plot of the measured hydrodynamic size as a function of sample concentration to obtain the dynamic Virial coefficient (also known as kd, or interparticle interaction parameter)
Mixture Viscosity: estimates the viscosity of a mixture of dispersants of known viscosity, using the assumption that the total viscosity is a volume fraction weighted sum of the component viscosities. The mean viscosity is based on the volume fraction and the individual viscosities of the component …
Protein Aggregation, Protein Mobility, Tech Talk »
Our portfolio of instruments to aid in biopharmaceutical research has grown significantly in recent years, thanks to innovation from our Bioscience Development Initiative as well as acquisitions of NanoSight, Viscotek and most recently, MicroCal. As a result,the amount of useful resources we have created for those interested in analyzing and characterizing proteins has also exploded.
This list guides you through 20 essential resources for the protein scientist at all stages of research & formulation development. I hope you find it useful. To explore our full, free archive of articles, whitepapers, application notes …
Dynamic Light Scattering, Microrheology, Particle size, Protein Mobility, Zeta potential, Zetasizer »
I am sure that you will have seen the activity around the launch of the Zetasizer Nano ZSP following its launch into the market last year. A lot of you may even have one of these instruments in your laboratory! Well, now is your chance to have your say as to whether or not it should win the SelectScience award for Best Spectroscopy Product of 2012. Voting is open now (and closes very soon!) therefore if you are also of the belief that the Zetasizer Nano ZSP is worthy of …Read the full story »
Corporate, Dynamic Light Scattering, Electrophoretic light scattering, Malvern Events, Meet the Experts, Microrheology, Protein Mobility, Zeta potential, Zetasizer »
After much discussion about the forthcoming addition to the Zetasizer Nano range, and build up of excitement around the launch, I can announce that the Zetasizer Nano ZSP has been officially released and is available to buy from your local Malvern office.
The ZSP is complimentary to the existing Zetasizer Nano instruments, and is now the premium system in the range. It can be used for the measurement of size, electrophoretic mobility of proteins, zeta potential of nanoparticles and surfaces, and optionally the microrheology of protein and polymer solutions. In addition to …
Recently, I have heard more and more people talking about protein mobility, what it means and how to measure it. So, I have decided to use this week’s blog as an opportunity to share some of Malvern’s expertise in this area.
Protein mobility, or protein electrophoretic mobility, is essentially the motion of protein molecules under the influence of an electric field that is applied across the fluid that they are dispersed in. The mobility of a protein is directly related to its charge as well as other factors such as electric …