Novel electrochemical sensing platform for accurate detection of benzylpenicillin based on a graphene oxide-manganese ferrite modified carbon paste electrode

Abstract

Antibiotic overuse and environmental disregard result in water supply contamination, caused antibiotic resistance. Given the global health concern, developing a sensitive, simple, and low-cost antibiotic sensor is critical. In this study, graphene oxide was incorporated with MnFe2O4 to modify the carbon paste electrode (CPE) as a new electrochemical platform for detecting benzylpenicillin, the widely used antibiotic. A comparative chemical and structural characterization of the synthesized MnFe2O4 nanoparticles (NPs) and GO/MnFe2O4 nanocomposites (NCs) verified that the successful integration of spherical particles of MnFe2O4 NPs onto GO nanosheets produces a rough surface. Furthermore, the structure and electrochemical characterization of the developed GO/MnFe2O4/CPE were conducted via field emission scanning electron microscope (FESEM), energy dispersive X-ray spectroscopy (EDX), cyclic voltammetry (CV), and impedance spectroscopy (EIS) techniques. The proposed electrode presented enhanced active surface area and electrocatalytic performed due to the superior features of the used modifiers, which work synergistically. The GO/MnFe2O4/CPE demonstrated a high-performance benzylpenicillin sensing platform, giving a detection limit of 145 nM and sensitivity of 15.16 μAμM-1cm−1 as measured by differential pulse voltammetry (DPV) within two dynamic ranges of 1–100 μM and 100–1000 μM. The created sensor was applied as a practical apparatus for the electrochemical determination of benzylpenicillin in water samples.