2D DIGE Western Blot HCP Detection and Coverage Determination: Advantages of Fluorescence over Colorimetric Detection

Biopharmaceutical products must be proved to be minimized as much as possible of contaminating host cell proteins (HCPs) prior to approval by the regulatory authorities. Commonly, ELISAs are used for HCP determination and authorities ask for clear and manifest proof that the antibodies used in the HCP ELISA are fit for purpose. Their suitability needs to be shown, not only by the obtained ELISA data, but also by determination of HCP coverage in %. So far a colorimetric 2D Western immunoblotting method has been used. But fluorescence detection using a 2D DIGE Western Blot has several advantages over the colorimetric detection while the HCP coverage of the two methods is comparable.