Enzyme Immobilization on Carboxyl-Functionalized Graphene Oxide for Catalysis in Organic Solvent

Carboxyl-functionalized graphene oxide (GO-COOH) was utilized to immobilize lipase. Fourier transform infrared (FTIR), UV visible, and X-ray photoelectron (XPS) spectra were measured to characterize lipase immobilization. At the optimal temperature of 40 degrees C, the immobilized lipase retains 80% of the hydrolytic activity of the native lipase. For catalyzing the enantioselective reaction in the organic solvent heptane, at 50 degrees C (optimal), the catalysis efficiency of the immobilized lipase is 1.6 times that of native lipase, and the immobilized lipase retains the selectivity of the native lipase. This work demonstrates that graphene oxide is a suitable support for immobilization of lipase for catalysis in organic solvent.