Amperometric response of hydrogen peroxide at carbon nanotubes paste electrodes modified with an electrogenerated poly(Fe(III)-5-amino-phenantroline): Analytical applications for glucose biosensing

Abstract

This work reports the catalytic activity of a polymer electrogenerated from Fe(III)-5-amino-1,10-phenantroline solution at a carbon nanotubes paste electrode (CNTPE) towards the oxidation and mainly the reduction of hydrogen peroxide. The important role of carbon nanotubes on the generation of poly(Fe(III)-5-amino-1,10-phenantroline) is demonstrated through the comparison with the behavior of graphite paste electrode (CPE). The polymer electrogenerated at CNTPE largely improves the amperometric detection of hydrogen peroxide at -0.100 V. The analytical application of the resulting electrode is demonstrated in connection with the design of a glucose biosensor based on the deposition of GOx and diluted Nafion on the top of the polymer-modified CNTPE. The quantification of glucose in human serum samples showed a good correlation with the values obtained by the spectrophotometric technique.