Optimization, Validation, and Use of Capillary Gel Electrophoresis for Quality Control Testing of Synagis®, a Monoclonal Antibody

Abstract

Capillary electrophoresis methods offer many advantages over their conventional electrophoresis counterparts including: greater precision, higher throughput, on-line detection and less waste. Capillary gel electrophoresis (CGE), using replaceable sieving polymers, is widely used as an alternative to SDS-PAGE and densitometry. CGE offers greater automation capabilities than SDS-PAGE and can be operated using conventional chromatography system software. This software for handling and analyzing data makes the validation of CGE methods look quite similar to the validation of an HPLC method. The same parameters can be examined, including: precision, accuracy, linearity, selectivity, range, robustness, and system suitability. There are, however, certain key elements that are critical to a successful CGE method validation. The CGE quantification method must be shown to be equivalent to SDS-PAGE with densitometry and should be presented such that the densitometry plots look like the electropherograms. In addition, the sensitivity of the methods must be compared and the CGE method must have comparable or better sensitivity to SDS-PAGE with Coomassie staining. The validation must also be performed using materials that might be tested during the course of a typical process (in-process samples) in their particular matrices. The other vital element is assuring that acceptance criteria for the validation have been set to reasonable ranges. These ranges must be determined in pilot studies that are executed prior to the validation studies. Under most CGE conditions, the acceptance criteria will be quite similar to those seen in HPLC validations. Overall, CGE methods can be validated to the same level of assurance as HPLC methods. The CGE method described here has been approved by the FDA and is used routinely for testing of Synagis®