Electrochemical High Sensitive Detection of Hydrogen Peroxide Based on Platinum-palladium Nano-enzyme Modified Microelectrode

Abstract

Hydrogen peroxide (H2O2) is widely distributed in living organisms and the environment, and its concentration is closely associated with human health. Therefore, the development of an efficient and sensitive detection method for H2O2 is imperative. In this study, a PtPd nano-enzyme composite was electrodeposited onto a platinum wire microelectrode (ME) using a one-step electrochemical deposition method to fabricate an H2O2 electrochemical sensor (PtPd/ME) with exceptional performance. The successful modification of PtPd on the electrode surface was confirmed by scanning electron microscopy (SEM) and X-ray energy dispersive spectroscopy (EDS). Chronoamperometry (i-t) was employed to investigate various technical parameters including sensitivity, detection limit, detection range, reproducibility, and anti-interference capability. The results demonstrate that the sensor exhibits a sensitivity of 11.94mAM-1 cm-2 with a detection limit of 0.034μM and a wide linear range from 31.25μM to 4.15mM while also demonstrating excellent anti-interference properties. These superior performances can be attributed to the strong catalytic activity towards H2O2 provided by PtPd nanoparticles as well as the fast electron transfer rate facilitated by microelectrodes. Furthermore, this sensor effectively enables real-time monitoring of H2O2 released by ascorbic acid-stimulated vascular endothelial cells and demonstrates its potential for detecting H2O2 in contact lens care solutions. These findings provide valuable insights for food and drug testing, and demonstrate great potential for monitoring key pathological processes within living cells.