Electrochemical sensing platform based on the carbon nanotubes/redox mediators-biopolymer system

A new electrochemical sensing platform was developed that relied on synergy between carbon nanotubes (CNT) and redox mediators that were co-immobilized in the biopolymer chitosan (CHIT). To demonstrate the concept, the redox mediator Toluidine Blue O (TBO) and CNT were integrated in CHIT and used for the determination of a reduced form of nicotinamide adenine dinucleotide (NADH). As compared to CHIT-TBO, the CHIT-TBO/CNT films displayed large amplification of a current due to the TBO-mediated oxidation of NADH at -0.10 V. This was discussed in terms of the TBO/CNT synergy that resulted in the improved charge propagation through the CHIT-TBO/CNT matrix.