Ultrasensitive photoelectrochemical biosensing based on biocatalytic deposition

The coupling of biocatalytic precipitation (BCP) to photoelectrochemical (PEC) biosensing for the development of rapid PEC sensors with ultrahigh sensitivity and excellent anti-interference ability is successfully realized. Horseradish peroxidase (HRP) was immobilized on the matrix of TiO2/CdS and 4-chloro-1-naphthol (4-CN) was chosen for the BCP-amplified PEC detection of H2O2. The HRP accelerated oxidation of 4-CN by H2O2 would yield insoluble product on the photoelectrode surface, on the basis of which the photocurrent be influenced. The detection limit of 5.0 x 10(-10) M (S/N = 3) for the determination of H2O2 was achieved. (C) 2011 Elsevier B.V. All rights reserved.