Fluoro-coumarin silicon phthalocyanine sensitized integrated electrochemiluminescence bioprobe constructed on TiO2 MOFs for the sensing of deoxynivalenol

Abstract

Herein, an effective integrated electrochemiluminescence (ECL) bioprobe was constructed based on F-couSiPc as co-reaction accelerator of tris (2,2′-bipyridine-n,n’)-, dichloride, hexahydrate (II) (Ru(bpy)32+) and TiO2 MOFs as carrier for developing a competitive-type ECL strategy for the sensing of deoxynivalenol (DON). Initially, TiO2 MOFs with high specific surface area and regular pore structure was employed to immobilize Ru(bpy)32+ and Mercapto-beta-cyclodextrin (β-CD), then sensitizer of F-couSiPc was introduced into the system by encapsulating into the cup-shaped cavity of β-CD, which mainly ascribed to the supermolecular self-assembly behavior, perfectly avoiding the aggregation of F-couSiPc. Due to the shortened electronic transmission distance, reduced energy loss and less reagent consumption, the integrated ECL reaction pattern between the luminescent Ru(bpy)32+ and sensitizer of F-couSiPc has shown improved luminous efficiency compared with the common intermolecular ECL reactions. Meanwhile, the (3-Aminopropyl) triethoxysilane (APTES), perylene-3,4,9,10-tetracarboxylic acid (PTCA) and carbon nanohorn (CNHs) nanohybrid (APTES-PTCA@CNHs), combing the remarkable advantages of CNHs with the desirable electronic and optical properties of PTCA, served as matrix to immobilize antigen (DON) with an increasing amount, and on account of the high affinity between the APTES and DON, a stable ECL performance was obtained. Based on the competitive immunoreactions, a facile and sensitive ECL immunosensor was constructed for the detection of DON, with excellent linear range from 0.1 pg/mL to 20 ng/mL and a detection limit of 0.03 pg/mL (S/N = 3).