Cephradine-Capped Gold Nanoparticle Modified Glassy Carbon Electrode for Trace Level Sensing of Triphenyltin Hydroxide

Abstract

Synthesis of highly stable gold nanoparticles (AuNps) was accomplished using cephradine (Cep) drug as the capping molecule and sodium borohydride as the reducing agent. Characterization studies such as ultraviolet-visible (UV–vis) spectroscopy confirmed the formation of AuNps while fourier transform infra-red (FT-IR) spectroscopy showed the interaction of AuNps with Cep. The size and shape of Cep-AuNps were investigated using atomic force microscopy (AFM) while their crystallinity was determined through X-ray diffractometry (XRD). The synthesized Cep-AuNps, after getting deposited on a glassy carbon electrode (GCE), proved as a highly responsive sensor for low-level detection of triphenyltin hydroxide (TPTH) using cyclic voltammetry (CV) as the determining mode in stirred solution. The developed sensor linearly responded to TPTH in the range of 1–80 nM with a lower detection limit (LDL) of 0.12 nM and R2 value of 0.9948 under optimized conditions. Importantly, the sensor was highly stable and reproducible, showing a relative standard deviation (RSD) value of 1.1% based on 15 replicative runs and proved to be extremely selective for TPTH with negligible interference in the presence of expected interfering species. The developed sensor was effectively utilized for monitoring TPTH in natural water samples.