Western Blot

The transfer or "blotting" of electrophoretic separated proteins from the gel matrix to a membrane (typically nitrocellulose or PVDF) followed by subsequent antibody-based detection on the surface of the membrane is called Western Blot or Immunoblot. Creative Proteomics provides western blotting analysis for the detection of a specific target protein out of a complex protein mixture, e. g. tissue homogenate or cell extract, using highly selective and sensitive antibody-antigen interactions. The resulting data allow both qualitative and semi-quantitative analysis of the protein of interest.

The Western Blot is a widely used analytical technique for the detection of specific proteins in a sample of tissue homogenate or extract. It uses gel electrophoresis to separate native proteins by 3-D structure, or denatured proteins by the length of the polypeptide. The separated proteins are then transferred to a membrane (typically nitrocellulose or PVDF), where they are stained with antibodies specific to the target protein. Western Blot is widely used in the fields of molecular biology, biochemistry, immune genetics and other molecular biology disciplines. Blotting is the transfer of macromolecules on immobilizing membranes for specific and sensitive detection.

In Western Blot analysis, the proteins of the sample are first separated in gel electrophoresis by isoelectric point (pI), molecular weight, electric charge, or a combination of these factors using various methods such as SDS-PAGE and IEF. Usually SDS-PAGE is employed for the separation, because all the proteins are solubilized and migrate in the same direction, and the epitopes are easier accessible due to the denaturing effect of SDS.