Silver nanowires-based signal amplification for CdSe quantum dots electrochemiluminescence immunoassay

Abstract

A novel silver–cysteine hybrid nanowires (SCNWs) with many reactive carboxyl and amine groups were prepared, which enable them to be used as idea signal amplifying labels in bioassays. A large number of CdSe quantum dots (QDs) were loaded on the SCNWs to develop amplified SCNWs–QDs electrochemiluminescence (ECL) signal probe. The PAMAM dendrimer-SCNWs nanohybrids covered on the electrode constructed an effective antibody immobilization matrix and made the immobilized biomolecules hold high stability and bioactivity. Based on the specific sandwich immunoreaction strategy, the detection antibody (Ab2)-SCNWs–QDs ECL signal probe was applied to the sensitive signal-on ECL immunoassay of human IgG. The SCNWs–QDs ECL not only opens promising new ECL emitting species, but also promotes the development of novel ECL signal-transition platforms for biosensing devices.