Photodynamic Properties of CdSe/CdS Quantum Dots in Intracellular Media

Abstract

CdSe/CdS quantum dots (QDs) were seeded into Jurkat cells using polyethylene glycol (PEG-1500) at different treatment times. Fluorescence microscopy images show that some QDs stick to the surface of the cells, while others appeared to be inside the cells. As it is difficult to ascertain whether the QDs are indeed inside the cells or just behind the cells, additional spectroscopic studies were performed. Photoluminescence spectra show that the fluorescence intensities of the CdSe/CdS QDs are different between samples at different treatment times. Interestingly, the fluorescence lifetimes are also different. This confirms the interaction between the CdSe/CdS QDs and the intracellular media and that the QDs were successfully seeded into the cells.