Thiol-ene click chemistry for the fabrication of Ru(bpy)32+-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− 3 M, with a satisfactory detection limit of 1 × 10− 6 M (S/N = 3).

► For the first time thiol-ene click chemistry was used for the immobilization of Ru(bpy)32+. ► The immobilization method is simple, fast, and efficient. ► The ECL sensor exhibited excellent stability in organic solvent and good reproducibility.