A Label-Free Interdigitated Microelectrodes Immunosensor for Pesticide Detection

Abstract

[EN] A sensitive, simple and label-free immunosensor for atrazine detection was developed. The immunosensor was based on antibody physisorption as immobilization technique. This technique was proposed as a cost-effective gold immuno-functionalization strategy alternative to SAM-based strategy for pesticide detection. Each step of immunosensor construction was characterized by electrochemical impedance spectroscopy, and the antibody-atrazine interaction was measured in a dynamic range from 10 to 150 ng/mL. This method was highly selective for atrazine and propazine, showing weak or no cross-reactivity to other similar compounds like terbutylazine. A limit detection of 10 ng/mL of atrazine was detected in PBS buffer with a good reproductibility. Lower limit detection in tap water was obtained.