Development of disposable electrochemical devices for detection of antibiotics sulfametoxazole and trimetoprim in supply water

Abstract

The increasing levels of emerging pollutants in aquatic environments have been of concern because of their high persistence in the environment. These substances include pesticides, hormones, pharmaceuticals, personal care products, and many of them do not have specific legislation. Among these, antibiotics have been highlighted because of their effects on human health, and bacterial resistance. In Brazil, sulfametazole and trimethoprim are among the most commonly consumed antibiotics. Antibiotic detection is conventionally performed by liquid or gaseous chromatography combined with mass spectrometry for identification and quantification. However, they have limitations that impede continuous monitoring, such as the use of expensive equipment that does not offer portability, trained personnel, long analysis times and large sample volumes. Alternatively, electrochemical sensors enable rapid analysis, miniaturization and portability for field analysis. The present project proposes the development of a disposable electrochemical sensor for the detection of sulfamethoxazole and trimethoprim in water supply. The devices will consist of printed electrodes, manufactured by screen printing technique on flexible plastic substrate. The working and auxiliary electrodes will consist of carbon paint and the reference of Ag / AgCl. Subsequently, the working electrode will be modified with composite of carbon nanotube covered by manganese oxide synthesized by hydrothermal route. MnO2 has interesting characteristics for sensing due to its catalytic properties, redox stability, low toxicity and reduced relative cost. The electrochemical properties of the alpha and gamma phases of MnO2 will be evaluated. The modified electrodes will be characterized by voltammetric techniques. The synthesized materials will be characterized by microscopic and spectroscopic techniques. The analytical parameters will be optimized for the simultaneous detection of both antibiotics. Finally, the detection of these species in samples of water supply will be carried out. (AU)