Enhancing the photoluminescence of peptide-coated nanocrystals

The high quantum yield (QY) of water-soluble peptide-coated nanocrystals with graded cadmium sulfide/zinc sulfide shells, which can be further enhanced by ultraviolet radiation, is demonstrated. The peptide-coated nanocrystals which also show redshifts in their emissions due to peptide binding, suggests about a coupling between the excitons of the nanocrystals and the molecular orbitals of the peptides. Results of fluorescence correlation spectroscopy (FCS) shows large saturation intensities, small hydrodynamic radii, little aggregation in nanocrystals, and demonstrates the high luminescent behavior of the nanocrystals. The observed linearly polarized emissions of peptide-coated nanorods shows their potential use in conformational dynamics.