Disclosed are a method of adhering active enzymes to an inert support, the product produced thereby, and a method of using the enzyme-coated support in enzyme-catalyzed reactions such as the glucose isomerase-catalyzed conversion of glucose to fructose. The method includes the steps of coating an inert support with a cationic copolymer, preferably a polyamine, and most preferably a di-C.sub.1-C.sub.6-alkylamino-epichlorohydrin copolymer, and then adhering enzyme to the coated support in the absence of any intervening cross-linking agent.