Quasi-Photonic Crystal Light-Scattering Signal Amplification of SiO2-Nanomembrane for Ultrasensitive Electrochemiluminescence Detection of Cardiac Troponin I

Signal amplification for electrochemiluminescence (ECL) plays a significant role in ultrasensitive detection of disease biomarkers. We report herein a new signal amplification strategy – quasi-photonic crystal nanomembrane-based light scattering enhancement for ECL signal amplification, via fabricating a novel close-packed monolayered SiO2-nanomembrane as solid-state ECL electrodes. In the system, the quasi-photonic crystal structure of the monolayered SiO2-nanomembrane led to intense light scattering within the nanofilm, which significantly increases the photon flux and then definitely improves the excitation number of the luminescent molecules (Ru(bpy)32+). Reinforced by the nanostructured electrode surface of the nanomembrane, the as-prepared ECL electrode exhibited significant ECL enhancement, ~ 77-fold enhancement in the classic Ru(bpy)32+-TPrA system. We further constructed a sandwich-type SiO2-nanomembrane based solid-state ECL immunobiosensor for ultrasensitive detection of cardiac troponin I (cTn...