LAUSR

MoS2 nanosheets can be applied as electrochemical biosensors to selectively and sensitively respond to the surrounding environment and detect various biomolecules due to their large specific surface area and unique physicochemical properties. In this paper, single-layer or few-layer MoS2 nanosheets were prepared by an improved liquid phase stripping method, and then combining the unique material characteristics of MoS2 and the metallic property of Au nanoparticles (AuNPs), Au@MoS2 composite nanosheets were synthesized based on MoS2 nanosheets. Then, the structure and properties of MoS2 nanosheets and Au@MoS2 composite nanosheets were comprehensively characterized. The results proved that AuNPs were successfully loaded on MoS2 nanosheets. At the same time, on the basis of the successful preparation of Au@MoS2 composite nanosheets, an electrochemical biosensor targeting dopamine was successfully constructed by cyclic voltammetry. The linear detection range was 0.5–350 μM, and the detection limit was 0.2 μM. The high-sensitive electrochemical detection of dopamine has been achieved, which provides a new idea for the application of MoS2-based nanomaterials in the biosensing of neurotransmitters. In addition, density functional theory (DFT) was used to explore the electrochemical performance of Au@MoS2 composite nanosheets. The results show that the adsorption of Au atoms on the MoS2 2D structure improves the conductivity of MoS2 nanosheets, which theoretically supports the possibilities of its application as a platform for the ultrasensitive detection of neurotransmitters or other biomolecules in the field of disease diagnosis.