In situ fabrication and design of a novel electrochemical sensor based on the Ag3.84Sn3S8@rGO nanocomposite for competitive ultra-detection of metronidazole in human urine

It is indispensable to develop an efficient technology for reducing contaminants in wastewater. Thus, we have developed a novel nanocomposite catalyst via the in situ formation of non-stoichiometric Ag3.84Sn3S8 on reduced graphene oxide (rGO) sheets. Significantly, we varied the concentration of rGO between 0.05 to 0.5% to get the optimal concentration (0.25%). To examine the application of the nanocomposite as a potential catalyst, we performed visible-light-induced mineralization of the antibiotic drug metronidazole (MNZ) and found the optimized efficiency. Based on this prospect, we have designed an electrochemical sensor for the ultra-detection of MNZ. The proposed sensor shows an excellent linear range (0.01-1500 nM), outstanding sensitivity (48 mu A nM(-1) cm(-2)), a significant limit of detection (LOD) (4 pM), excellent anti-interference ability (also in real samples) and good reproducibility.