Quantum dot-DNA bioconjugates for fluorescence resonance energy transfer-based biosensing

摘要

Semiconductor quantum dots (QDs) have unique photophysical properties which make them excellent fluorescence resonance energy transfer donors. However, lack of facile methods for conjugating biomolecules such as DNA, proteins and peptides to QDs have limited their applications. In this report, we describe a general procedure for the preparation of a synthetic peptide that can be covalently attached to DNA segments and used to facilitate the self-assembly of the modified DNA onto water soluble QDs. To characterize this conjugation strategy, dye-labeled DNA is first reacted with the synthetic peptide and the resulting peptide-DNA then self-assembled onto QDs. QD attachment is verified by monitoring resonance energy transfer efficiency from the QD donor to the dye-labeled DNA acceptor. QD-DNA bioconjugates assembled using this method may find applications as molecular beacons and hybridization probes.