Electrophoresis is a technique used to separate biopharmaceutical samples in order to provide a physicochemical assessment based on size (e.g. to assess identity and/ or purity) or charge (e.g. to detect sialic acid variants or deamidation).

BioPharmaSpec provide the below methods for your electrophoresis requirements.

Methodologies and Applications

Separation by Size

Most separations based on size are performed using traditional gel based electrophoresis (SDS-PAGE) or the newer technique of capillary gel electrophoresis (CGE or CE-SDS). In these techniques, molecular weights of components are defined via comparison to data obtained from analysis of a range of protein markers with known molecular weights. CE-SDS uses UV at 280nm to detect separated protein components and thus provides more reliable quantitative information relative to that obtained from densitometric analysis of gels.

Separation by Charge

Separations based on charge are performed using traditional IsoElectric Focusing (IEF) or the newer technique of imaging capillary isoelectric focusing (icIEF). The isoelectric points (pIs) of components within a biopharmaceutical product are defined via comparison to data obtained from analysis of a range of protein or small molecule markers with known pIs. As with CE-SDS, icIEF uses UV at 280nm to detect separated protein components and in the same way provides a more reliable quantitative information relative to that obtained from densitometric analysis of gels.

Although BioPharmaSpec scientists would recommend icIEF for the best resolution, other techniques such as Ion Exchange Chromatography (IEX) are also available.