Pollution is a concern in modern society, with pharmaceutical compounds being increasingly recognized as a major cause. Their improper disposal, along with their increased use, makes them reach the aquatic environment, causing potential harm to the aquatic ecosystem and consequently to human health. As a result, it is of extreme importance to develop sensors capable of monitoring pharmaceutical compounds in a sustainable and affordable way, with a rapid response [1]. The aim of this work is the development of an electrochemical sensor for the determination of venlafaxine in environmental waters, a widely prescribed antidepressant drug. The sensor is based on a carbon paper transducer modified with an iron-based metal-organic framework (MOF), MIL-100, by electrodeposition. Cyclic voltammetry analysis showed an irreversible oxidation peak at around 0.7 V (vs Ag/AgCl), with higher intensity compared with the unmodified carbon paper. Square-wave voltammetry was then applied to perform the optimization studies regarding electrolyte pH, technique parameters (frequency, step potential, amplitude), and analyte deposition, as well the study of its analytical performance. This electrochemical sensor shows promising analytical features in the determination of venlafaxine, taking advantage of the higher porosity and surface area of the MOF material, resulting in higher adsorption of the drug and thus higher electrochemical efficiency.

Reference:

[1] Miguel Tavares, Simone Morais, Álvaro Torrinha, Metal-organic frameworks based electrochemical sensors for emerging pharmaceutical contaminants in aquatic environment, Trends in Environmental Analytical Chemistry 47 (2025) e00271.