Amplified electrochemiluminescence detection of DNA-binding protein based on the synergy effect of electron and energy transfer between CdS nanocrystals and gold nanoparticles

In this work, we firstly enunciated the presence of synergy effect between the electron and energy transfer in an electrochemiluminescence (ECL) system involving the CdS NCs and Au NPs, based on which an amplified ECL biosensor was constructed for sensitive detection of DNA–protein interactions. Specifically, Au NPs modified on electrode, following by assembled probe DNA . Then the modified GCE was hybridized with SiO 2 @CdS/DNA conjugates. With DNA duplex as a rigid spacer, Au NPs could not only accelerate the electron transfer but also produce the surface plasma resonance upon excited ECL of CdS NCs. However, the enhanced ECL could be greatly suppressed by the binding of target protein. The prepared biosensor possesses excellent analytical performance with the linear range of target protein from 0.015 to 150   nM.