Amperometric identification of metronidazole in urine by Au-Pd core-shell nanoparticles dispersed in Laponite clay/glassy carbon electrode

Abstract

A colloidal suspension of Au-Pd nanocluster-dispersed laponite was synthesized by a single-step reduction of equimolar concentrations of HAuCl₄ and K₂PdCl₄ in the presence of laponite using ascorbic acid. UV-visible spectroscopy and SEM studies proved the formation of bimetallic core-shell Au-Pd on the laponite clay matrix. The metronidazole’s electrochemical behaviour was analyzed with bimetallic nanoparticles dispersed in a laponite composite modified glassy carbon electrode (GCE). An irreversible reduction peak was noted in cyclic voltammetry at +0.80 V vs. Ag/AgCl. Detection of metronidazole antibiotic drug at lower level in biological samples was analyzed by amperometric method and pulse voltammetry. A linear regression was achieved in the range between 0.5 and 10 µM in both methods. The present can be extended further to use for the sensitive and selective electrochemical detection of metronidazole in real urine samples.