Etching Triangular Silver Nanoparticles by Self-generated Hydrogen Peroxide to Initiate the Response of an Electrochemiluminescence Sensing Platform.

Abstract

This work outlines a versatile and high-performance electrochemiluminescence (ECL) platform that uses complex luminescent molecules [Ru(II) complex] formed by carbohydrazide (CON4H6) and tris(4,4'-dicarboxylicacid-2,2'-bipyridyl)ruthenium(II) dichloride [Ru(dcbpy)32+] as emitters to facilitate the intramolecular ECL mechanism for reducing the response distance and interference, and they were kept immobilized on a porous bismuth vanadate nanoarray (BiVO4 NA) to improve the orderliness of electron transfer. In addition, the detection was made depending on the etching of triangular silver nanoparticles (T-Ag NPs) by self-generated hydrogen peroxide (H2O2) to initiate the recovery response of the originally quenched ECL due to ECL-RET between the Ru(II) complex (donor) and T-Ag NPs (receptor). Because of the antibacterial application of dopamine, its own redox ability could produce more H2O2 for etching receptor T-Ag NPs under near-infrared (NIR) stimulation. Notably, in this system, the specific binding of antigens and antibodies with the autogenesis process of H2O2 and the ECL detection procedure are independent. Therefore, the proposed system can avert the impact of complex biological samples effectively, and the ECL efficiency of the Ru(II) complex can be readily utilized. On this basis, a biosensor is explored for the primary diagnosis of squamous cell carcinoma by detecting the biomarker named after cytokeratin fragment 19 (CYFRA21-1), from which an excellent linearity from 0.1 pg/mL to 50 ng/mL is achieved with a detection limit of 0.058 pg/mL. All of these results confirmed that this strategy can be a promising candidate for fabricating an ECL-based biosensor.