FRET from CdSe/ZnS Core-Shell Quantum Dots to Fluorescein 27 Dye

Semiconductor QDs have emerged as a novel class of fluorophore with unique photoluminescence properties, in particular, CdSe/ZnS core-shell QDs have been successfully used as biocompatible fluorescence resonance energy transfer donors. Here we report FRET between CdSe/ZnS core-shell QDs (donor) and organic dye fluorescein 27 (F27) (acceptor). The results demonstrate the occurrence of efficient energy transfer in the system and the FRET efficiency is not only influenced by the spectral overlap between the QD donor emission and acceptor absorption, it might depend on QDs surface effect also. Efforts are made to correlate quantitatively spectral dependence of FRET rate with acceptor absorption spectrum, Forster distance, transfer efficiency (E) obtained employing steady-state & time-resolved technique.