title: Imaging the cellular uptake of tiopronin-modified gold nanoparticles.
abstract: Well-dispersed gold nanoparticles (NP) coated with tiopronin were synthesized by X-ray irradiation without reducing agents. High-resolution transmission electron microscopy shows that the average core diameters of the NPs can be systematically controlled by adjusting the tiopronin to Au mole ratio in the reaction. Three methods were used to study the NP uptake by cells: quantitative measurements by inductively coupled plasma mass spectrometry, direct imaging with high lateral resolution transmission electron microscopy and transmission X-ray microscopy. The results confirmed that the NP internalization mostly occurred via endocytosis and concerned the cytoplasm. The particles, in spite of their small sizes, were not found to arrive inside the cell nuclei. The synthesis without reducing agents and solvents increased the biocompatibility as required for potential applications in analysis and biomedicine in general.
authors.affiliation: Institute of Physics, Academia Sinica, Nankang, Taipei 11529, Taiwan.
authors.forename: Xiaoqing
authors.initials: X
authors.lastname: Cai
authors.forename: Hsiang-Hsin
authors.initials: HH
authors.lastname: Chen
authors.forename: Cheng-Liang
authors.initials: CL
authors.lastname: Wang
authors.forename: Shin-Tai
authors.initials: ST
authors.lastname: Chen
authors.forename: Sheng-Feng
authors.initials: SF
authors.lastname: Lai
authors.forename: Chia-Chi
authors.initials: CC
authors.lastname: Chien
authors.forename: Yi-Yun
authors.initials: YY
authors.lastname: Chen
authors.forename: Ivan M
authors.initials: IM
authors.lastname: Kempson
authors.forename: Yeukuang
authors.initials: Y
authors.lastname: Hwu
authors.forename: C S
authors.initials: CS
authors.lastname: Yang
authors.forename: G
authors.initials: G
authors.lastname: Margaritondo
mesh_terms: D002470:Cell Survival; D002477:Cells / Q000000981:diagnostic imaging / Q000378:metabolism; D002478:Cells, Cultured; D004705:Endocytosis; D006046:Gold / Q000378:metabolism*; D006801:Humans; D013058:Mass Spectrometry; D053768:Metal Nanoparticles / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D011859:Radiography; D017356:Synchrotrons; D008625:Tiopronin / Q000138:chemical synthesis / Q000737:chemistry*; D014965:X-Rays
chemical_list: D006046:Gold; D008625:Tiopronin