▎ 摘　　要

An electrochemical sensor that can sensitively detect levodopa without fragile and expensive antibodies has been prepared on the basis of indium sulfide and graphene. The indium sulfide nanospheres synthesized by a hydrothermal method were grown on the surface of three-dimensional graphene prepared by chemical vapor deposition. The graphene maintains a good 3D structure and the indium sulfide nanospheres increases the specific surface area of graphene. The composite possesses a low detection limit of 87 nM (S/N = 3) and the sensitivity of it reaches 1.98 mu A mu M-1 cm(-1). Also, good electrochemical performance, selectivity, and stability make it available to be used for detecting real biomolecules.