SDS-polyacrylamide gel electrophoresis

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Why?

The method is a simple way to arrange proteins in a sample according to their size and visualize them as a nice ladder of bands in a gel. The method has many applications, including estimation of molecular mass and protein purity, monitoring of protein integrity and comparison of different protein samples.

Biosafe

The SDS-PAGE is commonly used to obtain an overview of a food enzyme for regulatory purposes, looking for its purity and batch-to-batch variation.

The sample is treated with the detergent SDS (sodium lauryl sulfate) and a reducing agent. The SDS binds to the proteins unfolding them, and the reducing agent cleaves the disulfide bonds. The resulting linear, negatively charged protein chains are run through the polyacrylamide gel matrix in electric field, which separates the chains primarily based on their size. The density of the gel, the size markers and the running time can be adjusted according to the expected sizes of the proteins. The size marker proteins run parallel to the samples are used to obtain approximate sizes for the proteins.

In a conventional SDS-PAGE gel the proteins are stained with Coomassie Brilliant Blue, which does not discriminate between different proteins. For the identification of the protein of interest in a complex protein pattern, a method based on a specific antibody or another protein-specific method can be used, if available.

To minimize the time and effort during testing, Biosafe asks you details about the sample and the protein of interest. All information will be kept strictly confidential.