ELECTROCHEMICAL SENSOR BASED ON ZnO-MODIFIED CARBON PASTE FOR SENSITIVE DETECTION OF TETRACYCLINE

In this paper, is studied the feasibility of preparing an electrochemical sensor based on carbon paste to determine one of the most commonly used antibiotics in our country, such as Tetracycline (TET). Various environmental and health agencies around the world emphasize moderate uses of these medications since they are often abused and can be disposed of indiscriminately with other untreated waste, becoming a potential for pollution of habitats or waters through which they may pass. The prepared sensor is based on carbon paste modified with 20% ZnO and after optimizing of indifferent electrolyte, pH and working conditions of the electrochemical techniques used, the detection limit for the target analyte TET was calculated from the calibration curve with the SWV technique, which resulted in about 4.5 ppm with RSD 9%, with a sensitivity of the method approximately 8 μA/ppm and a correlation above 0.99 for the linear range 3-18 ppm. Morphological characterization of the modified carbon paste with SEM and EDX, provide an overview of the distribution of the modifier in the paste and the sizes that correspond to nm dimensions.