Green electrochemical sensing of ampicillin using reduced graphene oxide-modified electrodes

Abstract

A “green” electrochemical sensor for the detection of ampicillin (AMP) was developed using a reduced graphene oxide-modified glassy carbon electrode (rGO/GCE). The sensor exhibited good performance with a linear detection range from 0.02 μM to 2.56 μM and a low detection limit of 6.75 nM. Characterization of the rGO material was carried out using Fourier-transform infrared (FT-IR) and Raman spectroscopy, confirming the successful reduction of graphene oxide and the restoration of electrical conductivity. The rGO/GCE sensor demonstrated high selectivity, minimal interference from common compounds, and good repeatability, reproducibility and long-term stability. Real-sample analysis in spiked urine achieved recovery rates of 97–103%, validated by high-performance liquid chromatography (HPLC). The results highlight the rGO/GCE sensor as a sensitive, reliable, and cost-effective platform for AMP monitoring in pharmaceutical applications.