Nanocomplexes with anchored Ru(bpy)²⁺ _3-tetraethylene pentamine electrochemiluminescence system: Self-enhanced coupled photothermal strategy detection of thyroglobulin

A synergistic amplified electrochemiluminescent (ECL) immunoassay was constructed by utilizing an efficiently self-enhanced signal tag and sensing substrate with satisfactory photothermal property for thyroglobulin ultra-sensitive detection. Concretely, tetraethylene pentamine (TEPA) was first attempted for the coreactant of Ru(bpy)2+ 3 , and mesoporous silica nanostars with large surface area and porous structure was designed as a support material to integrate Ru(bpy)2+ 3 and TEPA, forming a self-enhanced signal tag to improve ECL efficiency. Additionally, magnetic beads with excellent photothermal effect was used as ideal sensing substrate to obtain the further amplified ECL signal because of the accelerated electron diffusion and reaction process induced by increased electrode temperature under the near-infrared laser irradiation. With the self-enhanced and photo-thermal synergistic amplified strategy, the proposed ECL sensor showed a wide linear range from 10-5 to 10 ng/ mL with a low detection limit of 3.3 x 10-6 ng/mL. This work will provide a promising avenue to simplify the synthesis of self-enhanced ECL emitter complexes, and pave the avenue for achieving synergistic enhancement of ECL signals by incorporating probe substrates.