RAPID-DETERMINATION OF GLYCOPROTEINS AND GLYCOPEPTIDES BY PERIODIC ACID SCHIFF REAGENT DOT-BLOTTING ASSAY ON NITROCELLULOSE MEMBRANE

We present here an improved practical approach of determination of gly coproteins and glycopeptides by directly dot-blotting samples on nitro cellulose membrane and staining the membrane with periodic acid Schiff (PAS) reagent. We demonstrate that it is possible to eliminate the ti me-consuming fixation step as in the staining of glycoproteins in poly acrylamide gel after electrophoresis and to shorten other staining ste ps. At least 0.1 mug of glycan can be detected within 40 min. Poly(vin ylidene fluoride) membrane is an alternate choice for PAS staining. Th e choice of a proper membrane with smaller pore is important for the d etermination of glycopeptides. For the determination of glycopeptides of 3000-5000 molecular weight, a membrane with 0.1-mum pores is the be st suited. As various detergents and buffers do not prevent the bindin g of proteins onto membrane, this technique could be used effectively for screening glycoproteins and glycopeptides.