L-GSH@AgNPs deprotonation hyperfine coupling with Ru(Ⅱ/Ⅲ) accelerated anode electrochemiluminescence of Ru/GO nanosheet for 8-OHdG immunoassay in cells.

BACKGROUND

Electrochemiluminescence (ECL) systems leveraging Ru(Ⅱ/Ⅲ) complexes often suffer from limited quantum yields. The mercaptan amino acid induced metal nanoparticles aggregation has potential to prominently enhance ECL efficiency by accelerating coreaction pathways. To explore this mechanism, a new nanohybrid that composed of l-Glutathione (L-GSH) and silver nanoparticles (AgNPs) was designed to profile the radical moiety process and employed to construct immunosensor for the 8-hydroxyguanosine (8-OHdG) immunoassay in HepG2 hepatocellular carcinoma cells (HCC).

RESULTS

The Electron paramagnetic resonance (EPR) data confirmed that while the rich-amino L-GSH deprotonation hyperfine coupling with Ru(Ⅱ) shifted to the paramagnetism resonance structures of Ru(Ⅲ), the AgNPs synergistically catalyzed the hydroxyl radical to avail for Ru2+∗ excited state, by which the nanohybrids accelerated 11-folds ECL quantum yields higher than that of Ru/GO nanosheet. The high ECL quantum yield of the promising nanohybrids pushed the immune detection limit of 8-OHdG down to 1.2 × 10-2 pmol/L with the precision of 3.02 % and the recovery rate of 89.00 %-129.70 %.

SIGNIFICANCE: The highly efficient aggregation induced enhancement electrochemiluminescence (AIECL) coreaction mechanism that an aminyl deprotonation hyperfine coupling worked in synergy with metal-catalyzed hydroxyl radical, hastened high ECL quantum yields of L-GSH@AgNPs nanohybrids in Ru-based ternary ECL system. With exceptional sensitivity, precision, and recovery rates, this approach paved the way for rapid, reliable diagnostics in cell or liquid biopsies.