Spectroelectrochemical study of acetylsalicylic acid in neutral medium and its quantification in clinical and environmental samples

This paper describes the application of simultaneous electrochemical reduction and UV absorbance methods (spectroelectrochemical techniques, highlighting the derivative linear scan voltabsorptometry) in the determination of acetylsalicylic acid in neutral medium, using a platinum gauze electrode modified with nanocomposite of reduced graphene oxide with gold nanoparticles (rGO/AuNPs). In solution, the process involving one electron to produce the radical acetylsalicylate was observed. Such mechanism was confirmed by electronic paramagnetic resonance (EPR). This study demonstrated that the voltabsorptometric sensor is highly sensitive for the determination of acetylsalicylic acid, with a limit of detection of 0.26 μmol L−1. No significant interference was detected for ascorbic and uric acid in the determination of acetylsalicylic acid. The platinum gauze with rGO/AuNPs modified electrode device was successfully applied in the acetylsalicylic acid determination in an environmental samples (wastewater) and clinical (tablets of drugs and human urine) samples, and is a promising platform for a simple, rapid, direct and very sensitive analysis of acetylsalicylic acid.