A photoelectrochemical aptasensor for tetracycline based on the self-assembly of 2D MoS2 on a 3D ZnO/Au/ITO electrode

Two-dimensional (2D) layered MoS2 has good dispersion and adsorption properties, but being a narrow bandgap semiconductor limits its application in photoelectric sensing. In this study, a homogeneous photoelectrochemical sensor based on three-dimensional (3D) ZnO/Au/2D MoS2 is proposed for the ultrasensitive detection of tetracycline (TET). MoS2 is uniformly embedded on the 3D ZnO/Au surface by ordered self-assembly. The physical method of π–π interaction of MoS2 replaces the conventional use of chemically modifying aptamers on the electrode material surface. Under optimal conditions, this method has been successfully applied to the detection of TET in milk, honey, pig kidney and pork samples with reliable results. We believe that this study presents a method for the preparation of sensing carriers and target detection with great potential for application.