Enhancement effect of CdTe quantum dots–IgG bioconjugates on chemiluminescence of luminol–H 2O 2 system

Abstract

In this paper we developed an entirely new and highly sensitive luminol–H 2O 2 flow injection chemiluminescence system using the enhancement effect of CdTe quantum dots–IgG bioconjugates. Immunoglobulin G (IgG) as a kind of bio-molecule was conjugated to different sized CdTe semiconductor quantum dots (QDs). Using PL spectra and CL intensity profiles, it was found that chemiluminescence resonance energy transfer (CRET) was possibly occurring between CdTe–IgG bioconjugate and luminol. Under optimum conditions, increase of IgG concentration in CdTe–IgG bioconjugate resulted enhancing effect on CL intensity of luminol–H 2O 2 system. Moreover quenching effects on CL intensity by addition of different proteases can construct turn off biosensor for these proteases with low detection limits and wide linear range. Furthermore, the effects of various organic and inorganic species on CdTe–IgG bioconjugates enhanced luminol–H 2O 2 CL system were also studied in this paper.