a method for coating a substrate with silane that comprises contacting in an inert environment a substrate with a vapor containing a bifunctional silane , preferably a bifunctional silane containing an acrylic functionality . the method may further comprise the step of attaching a coating of polyacrylamide to the acrylic functionality by in - situ polymerization or the step of immobilizing acrylic - modified molecules by copolymerization with the acrylic functionality of the bifunctional silane . the substrate may be a capillary , a microchip , a bead , or a slide , preferably of glass . a substrate coated using the instant method , as well as a method for reducing eof in capillaries used for electrophoresis are also disclosed .