Enantioanalysis of L-Proline Using C60 Fullerenes as Chiral Selectors

Abstract

C60 fullerenes nanotubes, (1,2-methanofullerene C60)-61-carboxylic acid, diethyl (1,2-methanofullerene C60)-61–61-dicarboxylate and tert-butyl (1,2-methanofullerene C60)-61-carboxylic acid are proposed as chiral selectors for the design of enantioselective, potentiometric membrane electrodes. L-proline was selected as model analyte for the study of the behaviour of these electrodes. The best response was obtained when tert-butyl (1,2-methanofullerene C60)-61-carboxylic acid was used for the electrode's design, while the lower limit of detection was achieved for the enantioselective, potentiometric membrane electrode based on (1,2-methanofullerene C60)-61-carboxylic acid. The proposed electrodes can only be used for the enantioanalysis of L-proline. No linear and Nernstian response was obtained for D-proline. The surface of the electrodes can be regenerated by simply polishing, obtaining a fresh surface ready to be used in a new assay.