Influence of growth factor on internalization pathway of quantum dots into cells: PDGF effects internalization of QDs

The development of high-sensitivity and specificity probes that lack the intrinsic limitation of organic fluorescent dyes and sensitizers is of considerable interest in many areas of research, from cellular biology to molecular imaging and diagnostics. Quantum dots (QDs) are stable, bright fluorophores that can give high quantum yields, narrow emission bands, intense absorbance, very large Stokes shifts, high photostability and provide several emission colours under single excitation wavelength. In cell studies QD were observed to end up eventually in intracellular vesicles that could be identified in some cases as endosomes or lysosomes by organelle-speciflc labelling, or in a perinuclear region compatible with endosomal/lysosomal localisation. Real time and long term observations revealed that translation of these vesicles was possible in some cases, however the pathways of internalization and intracellular transport of QD in cells is still dim.