Graphene oxide(GO)-AuNPs@Ru(bpy)_3~(2+)nanocomposite was prepared by electrostatic interaction of AuNPs and Ru(bpy)_3~(2+). GO-AuNPs@Ru(bpy)_3~(2+)further reacted with GO to form GO-AuNPs@Ru(bpy)_3~(2+)which was used as the substrate material for ECL detection.Streptavidin(SA)can strongly bind with 4biotin molecules to form SA-biotin.The enhanced electrochemiluminescence(ECL)signal was obtained by the combination of SA-biotin with the recognition element such as aptamer.An ECL aptasensor for sensitive detec...