Determination of pesticide residues in food by electrochemical sensors based on nanoparticles-modified screen printed electrodes a review

Miniaturization, portability, high sensitivity, and selectivity, as well as a wide linear range, are characteristics of electrochemical sensors. In screen-printed sensors SPEs, electrode system consist of working, reference, and auxiliary electrodes are printed on a single substrate. SPEs can be the most suitable sensors for in-situ analysis, due to the fast and linear responses, low energy requirement, easy to prepare and ability to work at room temperature. The surface of SPEs can be modified with noble metals, inorganic or carbon nanoparticles, enzymes, DNA sequences, and molecularly imprinted polymers to improve their performance. A variety of bio-sensors are developed based of SPEs modified with enzymes for detection of pesticides. The electro active species are generated via enzymatic reactions and can be determined by electrochemical reactions. At the presence of pesticides, as inhibitor, the enzyme activity and electrical current are decreased, proportionally.