Robust and specific ratiometric biosensing using a copper-free clicked quantum dot-DNA aptamer sensor.

ABSTRACT: We report herein the successful preparation of a compact and functional CdSe-ZnS core-shell quantum dot (QD)-DNA conjugate via highly efficient copper-free "click chemistry" (CFCC) between a dihydro-lipoic acid-polyethylene glycol-azide (DHLA-PEG-N3) capped QD and a cyclooctyne modified DNA. This represents an excellent balance between the requirements of high sensitivity, robustness and specificity for the QD-FRET (Förster resonance energy transfer) based sensor as confirmed by a detailed FRET analysis on the QD-DNA conjugate, yielding a relatively short donor-acceptor distance of ~5.8 nm. We show that this CFCC clicked QD-DNA conjugate is not only able to retain the native fluorescence quantum yield (QY) of the parent DHLA-PEG-N3 capped QD, but also well-suited for robust and specific bi

SUBMITTER: Zhang H 

PROVIDER: S-EPMC3814187 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature