The Fabracation Of Gold Nanoparticle Decorated MoS₂ Nanocomposites-based Electrochemical Biosensor And Its Application

Mo S2 can be easily exfoliated to single-layer or few-layer sheets because of the weak van der Waals bonded sheets of S-Mo-S layers. Single-layer or few-layer Mo S2 nanosheets has been applied in many fields, such as field-effect transistors, photocatalysis for energy conversion and lithium batteries, which benefits from its unique properties. However, bare Mo S2 without decoration still cannot meet the needs in some areas. It is necessary for us to develop Mo S2-based functional nano materials.This essay synthesized gold nanoparticle functionalized Mo S2 with microwave-assisted method or electrodeposition method, combining the advantage of propoties of both Mo S2 and gold nanoparticle. For detecting different target objects, this thesis has designed three kinds of electrochemical biosensors based on the prepared nanocomposites:1. Gold nanoparticle functionalized Mo S2 films have provided a favorable microenvironment for glucose oxidase(GOx) to realize direct electrochemistry behavior. The sensor also has excellent stability and ideal reproducibility. At the same time, the sensor can realize the detection of glucose in real human serum sample.2. Two dopamine sensors have been developed based on Au NPs@Mo S2 nanocomposites, which have been synthesized by different methods. The Mo S2-based electrochemical sensors not only selectively determined dopamine in the presence of ascorbic acid, but also simultaneously detected ascorbic acid, dopamine and uric acid, respectively.3. The Mo S2-based aptasensor could individually and simultaneously detect adenosine triphosphate(ATP) and thrombin with high sensitivity and selectivity. Both linear range and detection limit are comparable or better than reported at present. Moreover, we used this aptasensor to construct an “AND” logic gate for ATP and thrombin detection.The designed sensors are very valuable in clinical diagnosis, biological molecule detection, protein determination and other fields. Therefore, the Mo S2-based nanocomposites maybe extended to construct other electrochemical biosensors for biological or chemical molecules detection.