Methodology for decentralized analysis: detection, quantification and in situ monitoring of pharmaceutical formulations removal by electro-Fenton

Abstract

Water quality is essential to both human and ecosystem health, and a fast detection of emerging pollutants is claimed, along with effective wastewater treatment plants to eliminate these types of substances. The goal of this study was the development of a sensitive and selective methodology to customize a handle device that meets this demand. Clozapine and its pharmacological formulation, Leponex®, were used as a model. The results obtained from the studies by differential pulse voltammetry (DPV) demonstrated that this methodology allows a simpler and cheaper decentralized analysis without losing sensitivity, performing electrochemical measurements in situ, in real-time and directly without sample treatment, with a good precision (RSD 3.7 %) and excellent accuracy (recoveries between 97.6 and 99.9 %). Moreover, the methodology was successfully used for direct follow-up the medicine removal in real samples by electro-Fenton (EF) treatment. The results gathered showed a relative error of less than 2 % concerning the measurements made with the conventional potentiostat. Bearing this in mind, the effectiveness of these electrochemical techniques used in tandem with the comfort and high specificity offered by the portable device, a more exhaustive control of water quality can be achieved, thus improving the quality of life in the planet.