Electrogenerated chemiluminescence of blue emitting ZnSe quantum dots and its biosensing for hydrogen peroxide

A novel method for the detection of hydrogen peroxide (H(2)O(2)) has been developed, based on electrogenerated chemiluminescence (ECL) of blue emitting ZnSe quantum dots (QDs) in aqueous solution. The weak ECL emission of ZnSe QDs was generated when the electrode potential was scanned from 0.0 to -1.4V (versus Ag/AgCl), and the ECL intensity was greatly enhanced in the presence of H(2)O(2) or dissolved oxygen. Under the optimal conditions, the dynamic range is from 6.10 x 10(-7) to 3.10 x 10(-4) M H(2)O(2), and the detection limit (at S/N=3) is 2.00 x 10(-7) M. The relative standard deviation (at 5.00 x 10(-5) M of H(2)O(2)) is 2.70% (n = 11). A possible reaction mechanism of ECL of ZnSe QDs was also investigated. As a novel biosensor, it was used to detect H(2)O(2) in the pig kidney (pk-15) cell, veto cell and mineral water, respectively. Moreover, the proposed biosensor showed a good reproducibility and potential application in real samples. (C) 2009 Elsevier B.V. All rights reserved.