Nitrocellulose-based assays for the detection of glycolipids and other antigens: mechanism of binding to nitrocellulose

A variety of simple and rapid assays for the detection of glycolipids by direct binding to nitrocellulose or binding to antibody-coated nitrocellulose, and probing with monoclonal antibodies are described. These include dot-blotting, charge shift electrophoresis and electroblotting. It is shown that the direct binding of the Leishmania major glycolipid to nitrocellulose is dependent on its lipid moiety, indicating that the mechanism of binding is probably via hydrophobic interactions. However, the L. major glycolipid from which the lipid moiety has been removed can still be detected by blotting onto nitrocellulose precoated with a monoclonal antibody directed to a carbohydrate epitope. The general approach of blotting onto antibody-coated nitrocellulose thus extends the usefulness of these techniques to cases in which the antigen to be detected does not bind directly to nitrocellulose.