Abstract
A simple, environment-friendly, cost-effective procedure is proposed for the synthesis of silver nanoparticles (AgNPs) using aqueous leaf extract of Ziziphus mauritiana (ZmL) as reducing as well as stabilizing agent and its application on glassy carbon electrode (GCE) for the detection of dopamine by cyclic voltammetry (CV). Results showed a substantial enhancement of peak current using Ag@GCE as compared to bare-GCE for the detection of neurotransmitter dopamine. The synthesized ZmL-AgNPs were characterized using ultraviolet-visible (UV-Vis) spectroscopy, Fourier transform infra-red (FT-IR) spectroscopy, X-ray diffraction (XRD) and atomic force microscopy (AFM). We investigated the electrochemical responses of both bare-GCE and Ag-assembled GCE using cyclic voltammetry to delineate the performance enhancement due to ZmL-AgNPs. The present ZmL-AgNP-assembled GCE displayed very high sensitivity and selectivity with excellent linear calibration range 10-100 mu M for detection of dopamine with a limit of detection and limit of quantification values 0.1 and 0.3 mu M, respectively. The sensor was successfully applied for dopamine detection in real urine samples.