Electrocatalytic detection of dimetridazole using an electrochemical sensor Ag@CPE. Analytical application. Milk, tomato juice and human urine

Abstract The electro-catalytic detection of the anti-protazaire Dimetridazole was performed using the carbon paste electrode modified with μAg@CPE silver micro-particles which demonstrate excellent catalytic activity towards the –NO2 attractor groups of the side chain of Dimetridazol molecules which is converted to –NHOH. The results obtained confirmed that the Dimetridazole reduction reaction is diffusion controlled. The electrochemical behavior is completely irreversible. The effect of the pH of the PBS solution on the Dimetridazole reduction reaction revealed that the number of protons and electrons were equal., the μAg@CPE electrode shows a wide range of concentration linearity with current, the detection limit and the quantitation limit were estimated respectively LOD ​= ​2,01 ​× ​10−7 ​M and LOQ ​= ​7,83 ​× ​10−7M, according to the cyclic voltammetry method. The morphology and chemical composition of the manufactured electrode paste were characterized by SEM and X-ray diffraction. Suggesting the formation of silver micro-particles on the carbon sheets. The size of the silver micro-particles synthesized at 200 ​°C was of the order of 2 ​μm. The electrochemical parameters diffusion coefficient (D) and catalytic rate constant (k) were calculated respectively Ddiff ​= ​1,335 ​× ​10−4 cm2/s and kcat ​= ​5, 214 ​× ​103 ​mol ​l−1 ​s−1. The proposed sensor was successfully tested for the determination of Dimetridazole in real samples like clearly commercial milk, tomato juice and human urine; the results found were very satisfactory.