Energy Transfer from C-Phycocyanin to Single-Walled Carbon Nanotubes

The energy transfer from C-phycocyanin (C-PC) to single-walled carbon nanotubes (SWNTs) in SWNT/C-PC hybrids is investigated using optical absorption and fluorescence spectroscopy. A suspension-dialysis method is used to assemble the SWNTs and C-PC proteins. The proteins cover partially the SWNT length as observed on atomic force microscopy images and transmission electron microscopy micrographs. Photoluminescence measurements show a strong enhancement of emission intensity of several SWNT species, while a strong decrease of the C-PC emission occurs in the presence of SWNTs. Our data suggest that a nonradiative resonance energy transfer takes place after the excitation of the C-PC with a high efficiency.