ZnO nanoparticles as an oxidase mimic-mediated flow-injection chemiluminescence system for sensitive determination of carvedilol

A simple, rapid and sensitive method was developed using ZnO nanoparticle (ZnO-NP) amplified flow-injection chemiluminescence to detect carvedilol, a non-cardioselective fl-blocker. It has been found that carvedilol strongly inhibits the chemiluminescence of luminol-H2O2 catalyzed by ZnO-NPs. Under optimum conditions, a linear working range for carvedilol concentrations from 5 x 10(-8) to 1.0 x 10(-8) mol L-1 (r > 0.9894, n=8) was obtained with a detection limit of 3.25 x 10(-9) mol L-1. The relative standard deviation for 8 repetitive determinations was less than 2.9% and recoveries of 99% and 102% were obtained. ZnO-NPs were synthesized using a green mechanochemical route. Transmission electron microscopy and x-ray diffraction were used to characterize ZnO-NPs. The method was successfully applied to detect carvedilol in pharmaceutical formulations. (C) 2014 Elsevier B.V. All rights reserved.