Fluorescent zinc oxide nanoparticles of Boswellia ovalifoliolata for selective detection of picric acid

Abstract

The use of Boswellia ovalifoliolata bark extract for the synthesis of zinc oxide nanoparticles (ZnO NPs) with benefits of eco-friendliness, low cost and compatibility for pharmaceutical and biological applications. In this paper, we report the biosynthesis of zinc oxide nanoparticles using plant extract and its application for the detection of picric acid (PA). The synthesized ZnO nanoparticles were characterized using UV-Vis spectroscopy, scanning electron microscopy (SEM), X-ray diffraction pattern (XRD), fourier transform infrared spectroscopy (FT-IR) and fluorescene spectroscopy. ZnO NPs in aqueous solution shows maximum absorption bands at 278 nm and fluorescence emission at 317 nm. The fluorescence emission of zinc oxide nanoparticle shows high selectivity towards picric acid (PA) and can be used as a fluorescent probe for the detection of PA via fluorescence quenching mechanism. The fluorescence quenching mechanism of picric acid may be due to the electron transfer process between ZnO NPs and picric acid which is confirmed by cyclic voltammetry (CV). The quenching efficiency of nanoparticle was calculated using Stern-Volmer equation. The limit of detection was found to be 1.83 μM for picric acid. The fluorescence property of the ZnO NPs can be utilized for cell imaging application as biosensors and also in the field of drug delivery.