Utilizing of Ag@AgCl@graphene oxide@Fe3O4 nanocomposite as a magnetic plasmonic nanophotocatalyst in light-initiated H2O2 generation and chemiluminescence detection of nitrite

A simple and sensitive chemiluminescence (CL) procedure was developed for the quantification of nitrite in aqueous solutions. The method is based on light-initiated generation of H2O2 by a magnetic Ag@AgCl@Graphene oxide nanocomposite and its subsequent redox reaction with nitrite ion in acidic medium. During the carbonate-catalyzed decomposition of produced peroxynitrite and energy transferring to uranine, a CL emission was observed at lambda=534 nm. Several factors affecting the CL intensity were investigated and optimized. Under optimum conditions, the CL intensity was directly proportional to the nitrite concentration in the range of 5-200 ng mL(-1). The limit of detection and relative standard deviation (for n=5; at a nitrite concentration of 70 ng mL(-1)) were 1.15 ng mL(-1) and 2.57%, respectively. The method was successfully applied to determine nitrite in food stuffs with recoveries in the range of 95.0-103.0% for the spiked samples. The accuracy of the method was evaluated by comparing the results with those obtained by analyzing the samples using a standard method. (C) 2015 Elsevier B.V. All rights reserved.