The potential of electrochemical pesticide analyses by green synthesized waste olive leaves based-silver nanoparticles

Pesticides are chemicals that negatively affect human health and the environment. Unconscious use of pesticides creates residues in foods or agricultural products and it also cause water and soil pollution. Quick and easy determination of pesticide residues is important for environmental inspections. For this reason, it is necessary to develop alternative methods to traditional methods such as chromatography for the determination of pesticide residues. Electrochemical sensors are new generation analytical devices developed for the determination of pesticides that enable rapid and practical analysis. Carbon paste electrodes used in the design of electrochemical sensors are modified using different materials such as silver nanoparticles. Silver nanoparticles used for modification could be synthesized using chemical methods, but these methods are harmful to the environment because toxic chemicals are used in the synthesis procedure. For this reason, the green synthesis technique was developed as an alternative to chemical techniques. In this study, waste olive leaves were used in green synthesis of silver nanoparticle as an electron precursor, the nanoparticles (OL-AgNPs) were characterized and modified carbon paste electrodes were prepared. The prepared modified carbon paste electrodes were used in the determination of thiocholine (as a product of hydrolysis of acetyl thiocholine by enzymatic reactions), H2O2 (as a product of many oxireductase enzyme reactions) and the widely used pesticides cyprodinil and mepanipyrim. The results showed that the modified carbon paste electrodes were more sensitive than the carbon paste electrodes for all analytes. It was clear that the modified carbon paste electrodes could be used in pesticide determinations.