Characterization of high-resolution carrier ampholytes

Since its inception, iCIEF has become a key technique for analyzing protein charge heterogeneity. Carrier ampholyte quality dictates the reproducibility of the separation itself as well as the potential for downstream assays through fractionation or iCIEF-MS coupling. A lack of consistency between CA lots from a single manufacturer can introduce significant problems in the application of CIEF as a reproducible tool in the biopharmaceutical industry, particularly in quality control.