Highly-sensitive and selective non-enzymatic L-cysteine sensor based on 3-mercaptopropyl trimethoxysilane functionalized Gd2O3 nanoparticles

Abstract

Herein, we report a facile fabrication of (3-mercaptopropyl) trimethoxysilane (MPTMS) functionalized gadolinium oxide nanoparticles (Gd2O3 NPs) and their application in sensing of L-Cysteine (L-Cys). The main purpose of MPTMS was to restrict the size in 6–8 nm range with better control on the morphology and surface activities of Gd2O3 NPs. Additionally, the electro-catalytic and surface properties of MPTMS@Gd2O3 NPs were explored for the selective and sensitive detection of L-Cys by using cyclic voltammetric (CV), chronoamperometric (CA) and differential pulse voltammetric (DPV) techniques. The as formed sensor displayed a good linear response between 1 and 100 µM and possessed high peak current intensity for electro-oxidation of L-Cys with a detection limit of 30 nM. The scope of the sensor was also assessed in the presence of different interfering species. The outcomes suggested the high stability, reproducibility and electro-catalytic activity of MPTMS@Gd2O3/Au sensor. The applicability of as formed sensor in spiked human urine samples has further increased the potential prospective of developed sensor in biomedical field with good recovery rate.