Highly-sensitive electrochemiluminescence biosensor for NT-proBNP using MoS2@Cu2S as signal-enhancer and multinary nanocrystals loaded in mesoporous UiO-66-NH2 as novel luminophore

Abstract

The accurate clinical diagnosis and prognosis keep ultrasensitive detection of NT-proBNP in a necessary topic. This work proposes a “signal-on” electrochemiluminescence (ECL) biosensor for ultrasensitive quantification of NT-proBNP with a newly designed luminophore. The luminophore is prepared by depositing Mn-doped ZnAgInS/ZnS nanocrystals in thermally-treated UiO-66-NH2 with mesoporous cages. Appropriate Mn doping enhances the stable luminescence, and the presence of ZnS shell reduces the surface defects to boost the quantum yield. The immunosensor is prepared by immobilizing the capture antibody on Au nanoparticles loaded MoS2@Cu2S modified electrode. The MoS2@Cu2S composite is synthesized by depositing MoS2 nanosheets on Cu2S snowflake, which forms distinct ripples on snowflake-like architecture to endow MoS2@Cu2S with considerable catalytic active sites as coreaction accelerator for amplifying the ECL signal. By labeling the detection antibody with the novel luminophore, a sandwich immunoassay is developed for ECL detection of NT-proBNP with a linear scope of 1 fg mL−1–100 ng mL−1 and a detection limit of 0.41 fg mL−1. Considering the excellent stability and selectivity, this paper exploits an innovative way to synthesize MOFs based luminophores and offers a powerful and responsible method for clinical assessment of biomarkers.