Lipase-immobilized magnetic chitosan nanoparticles for kinetic resolution of (R,S)-ibuprofen

Chitosan (CS)–poly[N-benzyl-2-(methacryloxy)-N,N-dimethylethanaminium bromide] coated magnetic nanoparticles were prepared by co-precipitation method via epichlorohydrin CS cross-linking reaction and were used in the kinetic resolution of (R,S)-ibuprofen by enantioselective esterification. Enzyme immobilized onto the surface of the new magnetic supports with the use of N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (EDC)/N-hydroxysulfo-succinimide sodium salt (sulfo-NHS) procedure demonstrated high catalytic activity that enabled us to obtain (S)-methyl ester of ibuprofen with high enantioselectivity (E = 50.6). The chiral compounds that resulted from the application of magnetic nanoparticles were analyzed with the use of chiral stationary phases. It should be emphasized that the main advantage of the support is the possibility to magnetically recovery and effective separation (even up to 5 s) from the reaction mixture with the use of magnet. The properties of magnetic particles allow for better optimization and may reduce the total costs of the esterification reaction of ibuprofen. Moreover, the application of lipase-immobilized magnetic supports enables to maintain high enantioselective activity after repeated use.