Highly sensitive and selective glucose biosensing at carbon paste electrodes modified with electrogenerated magnetite nanoparticles and glucose oxidase.

FAUSTO NAHUEL COMBA; MARIA DOLORES RUBIANES; LOURDES CABRERA; SILVIA GUTIERREZ; GUSTAVO RIVAS

ELECTROANALYSIS

WILEY-V C H VERLAG GMBH

Año: 2010 vol. 22 p. 1566 - 1572

1040-0397

This work reports the advantages of carbon paste electrodes modified with electrogenerated magnetite nanoparticles. The nanoparticles present catalytic activity towards the reduction of hydrogen peroxide allowing the detection of this important bioanalyte at very low potentials. The incorporation of glucose oxidase (GOx) together with electrosynthesized magnetite nanoparticles in a carbon paste matrix have made possible the development of a sensitive and selective glucose biosensor. The effect of the amount of GOx and magnetite present in the composite on the response of the biosensor was critically evaluated. The biosensors demonstrated to be highly selective, with negligible interference of easily oxidizable compounds like ascorbic acid and uric acid. The proposed biosensor was also challenged with human blood serum demonstrating an excellent correlation with the glucose concentrations obtained with the spectrophotometric method.