Factors affecting the performance of sodium dodecyl sulfate gel-filled capillary electrophoresis

Sodium dodecyl sulfate-polymer capillary electrophoresis for the analysis of cell culture proteins

The application of sodium dodecyl sulfate (SDS)-polymer capillary electrophoresis (CE) to the analysis of proteins of hybridoma cell culture supernatant is demonstrated. All steps of the developed analysis are shown and discussed. Following optimization of sample preparation and concentration, as well as of the mode of injection all main protein components were separated with high resolution and selectivity. Proteolytic degradation of IgG, due to microbial contamination, was observed on SDS-gel CE and capillary zone electrophoresis (CZE). The technique was applied to monitor the cell cultivation process and concentrations of main components are demonstrated. IgG was found to increase from initially 5 mg/L to 20 mg/L after 4 days and to > 130 mg/L after 14 days of cultivation. The techniques may be applied to other biotechnological processes for the production or purification of proteins.

Sodium dodecyl sulfate polyacrylamide gel- and replaceable polymer-filled capillary electrophoresis for molecular mass determination of proteins of pharmaceutical interest

Performance of commercially available replaceable SDS polymer-filled capillary electrophoresis (rPGCE) systems were evaluated for the determination of the molecular mass of proteins of pharmaceutical interest. The mass values obtained by these systems were compared with those obtained by SDS-PAGE and high-performance size exclusion chromatographic (HPSEC). The molecular masses of proteins determined by rPGCE were not significantly different and agreed closely with those obtained by SDS-PAGE and with the theoretical values of the proteins. HPSEC gave the least reliable data. Performance of the SDS crosslinked polyacrylamide gel-filled capillary electrophoresis system was superior to that of the commercially available rPGCE systems. Nevertheless, the rPGCE systems present significant advantages over the conventional SDS-PAGE and HPSEC methods for rapid analysis and improved precision for the determination of the molecular masses of proteins of pharmaceutical interest.