A new multifunctional electrocatalyst based on PbS nanostructures decorated with graphene/polyaniline-modified glassy carbon electrode for selective detection of non-steroidal anti-inflammatory drug naproxen

Abstract

Naproxen (NAP), a well-known anti-inflammatory drug, has also been considered for its antiviral prospective and acceptable potential for in vitro activity against serious respiratory syndrome-related coronavirus (SARS-CoV) and anti-influenza activity. However, designing a selective, sensitive and efficient electrocatalyst for the determination of NAP is still a great challenge. In this research, a new electrocatalytic sensor was constructed for the electrochemical recognition of NAP by a glassy carbon electrode modified with PbS nanostructures incorporated graphene/polyaniline nanocomposite. The synthesized samples were characterized by physicochemical analyses like EDS, XRD, FTIR, FESEM, and PL. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV) were carried out to examine the electrocatalytic behavior of the modified electrodes. The EIS plot obviously demonstrated rapid electron transport at low frequencies for the PbS/graphene/PANI/GC electrode. It was observed that the PbS/graphene/PANI/GC electrode exhibited better-defined oxidation peaks, and greater peak currents for NAP detection compared to other electrodes. Under the optimum conditions, the proposed PbS/graphene/PANI nanoplatform provided a reliable linear range of 1 to 100 µM with a detection limit as low as 0.08 μM. Meanwhile, the PbS/graphene/PANI electrode possessed acceptable selectivity, good repeatability with an RSD of about 2.6 %, and a reduction of about 3 % after two weeks, and long-term stability of about 97 % of its original response for the recognition of NAP. Furthermore, the constructed electrode demonstrated NAP detection in real samples, such as human plasma and urine with good recoveries ranging from 98.8 % to 99.9 %, suggesting its promising prospects in clinical diagnostics.