Synthesis of CuGa2O4/MoS2 nanocomposite and its electrogenerated chemiluminescent sensing application

In this work, spinel-type CuGa2O4 nanoparticles were incorporated with MoS2 nanosheets to obtain uniform CuGa2O4/MoS2 nanocomposite which could be used to fabricate high efficient electrochemical platform based on its synergetic effect. Strong anodic electrogenerated chemiluminescence (ECL) of Ru(bpy)32+ obtained at MoS2 nanosheets modified electrode was greatly inhibited in the presence of CuGa2O4 nanoparticles. The resonance energy transfer (RET) between Ru(bpy)32+ ECL and CuGa2O4/MoS2 nanocomposite should be responsible for the decrease of ECL signal. Peroxide oxidase-like properties of CuGa2O4 nanoparticles endowed its ability to interact with cholesterol and the pathway of RET was cut off, leading to the recovery of ECL signal. Under the optimal condition, cholesterol could be sensitively detected in the range of 0.5–6 μM, and the limit of detection was determined as 0.1 μM. The modified electrode exhibited excellently repeatability, reproducibility, and long-term stability, and could be used to detect cholesterol in serum samples. The result suggested that the incorporation of spinel-type metal oxide with 2D material will bring new progress in ECL biosensor.