Citrate capped Au-nanoparticles mounted on L-cysteine self-assembled monolayer modified gold DVD electrode as an electrochemical sensor for acetaminophen

Abstract

Acetaminophen (N-acetyl-p-aminophenol) is a widely used analgesic and antipyretic medicine. It contains phenolic hydroxyl group, which is an electrochemical active group and can be oxidized [1]. Owing to high specific surface area, excellent electrical conductivity, and high electrocatalytic activity, gold nanoparticles (AuNPs) have attracted much attention in recent years. Acting as ideal materials, they have been widely applied to the fields of electronics, catalysis, and biosensors [2].<br><br>Present research investigates the electrochemical behavior of acetaminophen at a novel modified electrode which has been consisted of citrate capped AuNPs (Cit-AuNPs) mounted on L-cysteine self-assembled monolayer modified gold DVD electrode (Au-DVDtrode). The AuNPs were prepared by reduction of HAuCl4 with sodium citrate solution. Characterization of the modified electrode was achieved using scanning electron microscopy, electrochemical impedance spectroscopy and cyclic voltammetry. The electrochemical behavior of acetaminophen at bare Au, bare Au-DVDtrode and Cit-AuNPs/L-cysteine/Au-DVDtrode were compared, suggesting that the modified DVDtrode significantly enhances the oxidation peak current of acetaminophen.<br><br>A good linear relationship in the range of 4 ×10-5 - 1×10-3 mol L-1 of acetaminophen was obtained with a detection limit of 1.1 ×10-5. Also, the %RSD was achieved to be 5.4%. Finally, the modified DVDtrode was successfully used to detect acetaminophen in commercial tablets. The sensor shows great promise for simple, sensitive, and selective detection acetaminophen.