Thiol-ene click chemistry for the fabrication of Ru(bpy) 3 2+-based solid-state electrochemiluminescence sensor

A novel method based on click chemistry for the immobilization of Ru(bpy)32+ derivative on electrode to fabricate a solid state electrochemiluminescence (ECL) sensor was reported. Pentenyl functionalized Ru(bpy′)3Cl2 was synthesized and immobilized on a (3-mercaptopropyl) trimethoxysilane (MPTMS) pretreated indium tin oxide (ITO) substrate via thiol-ene click chemistry reaction between its alkenyl group and the sulfhydryl group of MPTMS. The immobilization method is simple, fast, and efficient. More importantly, the resulting Ru(bpy′)32+ monolayer film exhibited excellent stability in organic solvent, which is superior to many previously reported methods. Using tri-n-propylamine (TPrA) as a model analyte, the ECL sensor gave a wide linear range over 5×10−6 to 5×10−3M, with a satisfactory detection limit of 1×10−6M (S/N=3).