RAPID METHOD FOR ASSAY OF QUANTITATIVE BINDING OF SOLUBLE-PROTEINS AND PHOTOSYNTHETIC MEMBRANE-PROTEINS ON POLY(VINYLIDENE DIFLUORIDE) MEMBRANES

For quantitative immunoassay on transfer membranes, a rapid and reliab le method was developed whereby more than 90% of proteins are retained on poly(vinylidene difluoride) (PVDF) membranes. Binding of proteins on PVDF was assessed for a photosynthetic membrane and soluble cell ex tracts from the cyanophyte Synechocystis PCC6714, and with bovine seru m albumin and rabbit serum. Binding of protein samples to PVDF was muc h better than by the capillary-draw or vacuum-filtration methods. Furt her, for enzyme immunoassays the PVDF procedure developed here allows detection of antigens in the mu g range in crude protein samples. (C) 1998 Elsevier Science B.V.