Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Optical characterization of colloidal CdSe quantum dots in endothelial progenitor cells | Molnár et al. Journal of Nanobiotechnology 2010 8 2 http content 8 1 2 JOURNAL OF NANOBIOTECHNOLOGY RESEARCH Open Access Optical characterization of colloidal CdSe quantum dots in endothelial progenitor cells Mátyás Molnár1 2 3 Ying Fu1 Peter Friberg2 3 Yun Chen2 3 Abstract We have quantitatively analyzed the confocal spectra of colloidal quantum dots QDs in rat endothelial progenitor cells EPCs by using Leica TCS SP5 Confocal Microscopy System. Comparison of the confocal spectra of QDs located inside and outside EPCs revealed that the interaction between the QDs and EPCs effectively reduces the radius of the exciton confinement inside the QDs so that the excitonic energy increases and the QD fluorescence peak blueshifts. Furthermore the EPC environment surrounding the QDs shields the QDs so that the excitation of the QDs inside the cells is relatively weak whereas the QDs outside the cells can be highly excited. At high excitations the occupation of the ground excitonic state in the QD outside the cells becomes saturated and high-energy states excited resulting in a large relaxation energy and a broad fluorescence peak. This permits in concept to use QD biomarkers to monitor EPCs by characterizing QD fluorescence spectra. Background The use of colloidal quantum dots QDs is one of the most exciting developments in nanobiotechnology. Because of their high durability and unique optical properties QDs are widely used as fluorescent labelling agents for in vitro and in vivo bioimagings such as cellular labeling deep tissue imaging and fluorescent resonance energy transfer donors 1 . Surface modified and water-soluble QDs open a new era in cell imaging and bio targeting as transport vehicles for therapeutic drug delivery to different diseases such as cancer and atherosclerosis 2-5 . Endothelial progenitor cells EPCs are heterogeneous groups of endothelial cell precursors which are circulating in the blood vessel. These cells play an important
