Efficient electrochemiluminescence of perylene nanocrystal entrapped in hierarchical porous Au nanoparticle-graphene oxide film for bioanalysis based on one-pot DNA amplification

Abstract

Although the perylene (Pe) affords the high quantum efficiency, its electrochemiluminescence (ECL) depends on organic solvents because of the serious aggregation-caused quenching effect in aqueous media, which impedes its application in ECL biological analysis. In this work, the hierarchical porous Au nanoparticle-graphene oxide nanocomposites(Au-GO) were prepared by using oleylamine as a reductant to generate Au nanoparticles which are intercalant to extend the intersheets distance of graphene oxide. Then the Au-GO could act as matrix for perylene nanocrystals (PeNCs) to load via π-π stacking which could prevent PeNCs from the self-aggregation to achieve an intense ECL of PeNCs in aqueous media. Consequently, a novel ternary ECL system was established with the perylene nanocrystals entrapped in Au-GO as ECL emitter, H2O2 as coreactant and hemin/G-quadruplex as a coreaction accelerator. Furthermore, combined with the one-pot target-catalyzed hairpin assembly induced strand displacement amplification strategy, we proposed a sensitive sensing method to achieve microRNA (miRNA) promising detection with a limit of detection down to 3.3 aM and a wide detection range from 0.01 fM to 10 pM. Importantly, this work provides a new direction for solving the self-aggregation of organic ECL luminophores.