Gold-Iron Bimetallic Nanoparticles Impregnated Reduced Graphene Oxide Based Nanosensor for Label-Free Detection of Biomarker Related to Non-Alcoholic Fatty Liver Disease

摘要

We report for the first time a microwave assisted, one pot, direct, and facile synthesis of monodispersed iron-gold bimetallic nanoparticles (BNPAu-Fe) using glucose as a reducing agent in merely 90 s. The as such synthesized BNPAu-Fe were thoroughly characterized using UV-Vis, XRD, TEM, EDX, elemental mapping, and raman spectroscopy. These BNPAu-Fe were further impregnated with reduced graphene oxide (rGO) and coated onto glassy carbon electrode (GCE) to develop a sensor probe for label free electrochemical detection of acetaminophen, which is considered to be a most potent biomarker related to non-alcoholic fatty liver disease. The sensor probe was systematically characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The BNPAu-Fe-rGO nanocomposite matrix showed the sensing of acetaminophen with a wide dynamic range between 50 and 800 nM with detection limit (DL) of 0.14 nM (+/- 0.05) nM (RSD<4.12 %) that was lower compared to previously reported acetaminophen sensors. To show the practical application of the sensor probe, acetaminophen was detected in human urine samples, which showed the percentage recovery between 86.65 % and 91.32 %. To the best of our knowledge, this is the first report where BNPAu-Fe impregnated rGO was used to detect acetaminophen. Interferences due to various molecules such as glucose, serum albumin, glycine, glutamic acid, alanine, citric acid, and ascorbic acid were tested individually and in mixed sample. Long-term stability of sensor probe was examined which was found to be stable up to 12 weeks. The sensor fabricated using BNPAu-Fe-rGO nanocomposite has many attractive features such as; simplicity, rapidity, and label free detection, hence it could be a method of choice for acetaminophen detection in clinical settings.