Non-specific binding to protein A Sepharose and protein G Sepharose in insulin autoantibody assays may be reduced by pre-treatment with glycine or ethanolamine.

Insulin autoantibody (IAA) microassays are widely used for predicting type 1 diabetes. As levels of IAA are often low in type 1 diabetes, non-specific binding (NSB) needs to be minimised if assays are to achieve high analytical sensitivity. IAA microassays use protein A Sepharose (PAS) or protein G Sepharose (PGS) to isolate the antibody-bound label, but NSB by the gel can differ between commercially-produced batches.