Construction of a label-free electrochemical immunosensor based on a Co9S8/Co3C@C dual-heterojunction for the detection of diethylstilbestrol

Abstract

Building heterogeneous structures can increase the rate of electron transport, generate synergistic effects, and get around the limitations of a single component. In order to create a label-free electrochemical immunological sensor, we created nanosheets with a dual-heterogeneous structure (Co₉S₈/Co₃C@C) using ZIF-67. Diethylstilbestrol (DES) was detected sensitively in environmental samples (groundwater and lake water). This sensor has an acceptable detection ability, a wide linear response (0.000384–6 ng mL⁻¹), and a low detection limit (3.24 fg mL⁻¹) due to the excellent conductivity of the nanosheets. The stability, selectivity, and sensitivity of the electrochemical immunosensor are satisfactory. It is an effective, practical, and quantitative detection technique.