Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Size-dependent endocytosis of gold nanoparticles studied by three-dimensional mapping of plasmonic scattering images | Wang et al. Journal of Nanobiotechnology 2010 8 33 http content 8 1 33 JOURNAL OF NANOBIOTECHNOLOGY RESEARCH Open Access Size-dependent endocytosis of gold nanoparticles studied by three-dimensional mapping of plasmonic scattering images Sheng-Hann Wang1 2t Chia-Wei _ee1 3t Arthur Chiou2 Pei-Kuen Wei1 2 Abstract Background Understanding the endocytosis process of gold nanoparticles AuNPs is important for the drug delivery and photodynamic therapy applications. The endocytosis in living cells is usually studied by fluorescent microscopy. The fluorescent labeling suffers from photobleaching. Besides quantitative estimation of the cellular uptake is not easy. In this paper the size-dependent endocytosis of AuNPs was investigated by using plasmonic scattering images without any labeling. Results The scattering images of AuNPs and the vesicles were mapped by using an optical sectioning microscopy with dark-field illumination. AuNPs have large optical scatterings at 550-600 nm wavelengths due to localized surface plasmon resonances. Using an enhanced contrast between yellow and blue CCD images AuNPs can be well distinguished from cellular organelles. The tracking of AuNPs coated with aptamers for surface mucin glycoprotein shows that AuNPs attached to extracellular matrix and moved towards center of the cell. Most 75-nm-AuNPs moved to the top of cells while many 45-nm-AuNPs entered cells through endocytosis and accumulated in endocytic vesicles. The amounts of cellular uptake decreased with the increase of particle size. Conclusions We quantitatively studied the endocytosis of AuNPs with different sizes in various cancer cells. The plasmonic scattering images confirm the size-dependent endocytosis of AuNPs. The 45-nm-AuNP is better for drug delivery due to its higher uptake rate. On the other hand large AuNPs are immobilized on the cell membrane. They can be used to reconstruct the cell morphology. Background Gold nanoparticles AuNPs are .
