A sensitive immunosensor via Pd@Au < sub > 0.85 < /sub > Pd < sub > 0.15 < /sub > in situ electrocatalysis generating H < sub > 2 < /sub > O < sub > 2 < /sub > for quenching electrochemiluminescence of Ir(pbi) < sub > 2 < /sub > (acac)@Ti < sub > 3 < /sub > C < sub > 2 < /sub > T < sub > x < /sub > MXene-PVA

Talanta. 2024 Apr 24;275:126125. doi: 10.1016/j.talanta.2024.126125. Online ahead of print.ABSTRACTThe establishment of rapid target analysis methods for cytokeratin fragment antigen 21-1 (CYFRA 21-1) is urgently needed. [Ir(pbi)2(acac)] (pbi = 2-(4-bromophenyl)-1-hydrogen -benzimidazole, acac = acetylacetonate) as traditional electrochemiluminescence (ECL) luminophores has been confined due to its non-negligible dark toxicity and poor water solubility leading to poor biocompatibility and electrical conductivity as an organic molecule. Hence, to overcome this limitation, [Ir(pbi)2(acac)] can be effectively loaded on the polyvinyl alcohol hydrogel modified Ti3C2Tx MXene surface (Ir@Ti3C2Tx-PVA) as sensing platform which can emit high ECL signals. Then, a quenching strategy was proposed to fabricate an ECL sandwich immunosensor using H2O2 as quencher molecules which can generated by Pd@Au0.85Pd0.15. Especially, the generation of O2 to H2O2 can be achieved through a two-electron (2e-) reaction pathway by Pd@Au0.85Pd0.15, to overcome the restriction that the H2O2 was virtually impossible to label or immobilize on the non-enzyme nanomaterials. The proposed ECL assay achieves a response to CYFRA 21-1 within the range of 0.1 pg/mL-100 ng/mL, with a detection limit of 8.9 fg/mL (S/N = 3). This work provided a feasible tactic to seek superior-performance ECL luminophore and quencher consequently set up a novel means to makeup ultrasensitive ECL biosensor, which extended the utilizatio...
Source: Talanta - Category: Chemistry Authors: Source Type: research