title: Endocytosis, intracellular transport, and exocytosis of lanthanide-doped upconverting nanoparticles in single living cells.
abstract: Lanthanide-doped upconverting nanoparticles (UCNPs) have recently attracted enormous attention in the field of biological imaging owing to their unique optical properties (near-infrared excitation followed by photoluminescence in the visible spectral range). For biological applications, it is critical to understand the interaction between these nanoparticles and biological systems at the cellular level. In this paper, using epi-fluorescence microscopy with 980-nm excitation, a full intracellular pathway composed of endocytosis, active transport, and exocytosis was clearly visualized for PEG-phospholipid-coated UCNPs in single HeLa cells, which was experimentally feasible mostly thanks to the excellent photostability and low cytotoxicity thereof. Each step in the pathway was characterized and identified by various chemical inhibition studies and spectroscopic measurements.
authors.affiliation: Laboratory for Advanced Molecular Probing, Research Center for Convergence Nanotechnology, Korea Research Institute of Chemical Technology, Daejeon 305-600, Republic of Korea.
authors.forename: Yun Mi
authors.initials: YM
authors.lastname: Bae
authors.forename: Yong Il
authors.initials: YI
authors.lastname: Park
authors.forename: Sang Hwan
authors.initials: SH
authors.lastname: Nam
authors.forename: Jeong Hyun
authors.initials: JH
authors.lastname: Kim
authors.forename: Kyunghee
authors.initials: K
authors.lastname: Lee
authors.forename: Hyung Min
authors.initials: HM
authors.lastname: Kim
authors.forename: Byeongjun
authors.initials: B
authors.lastname: Yoo
authors.forename: Joon Sig
authors.initials: JS
authors.lastname: Choi
authors.forename: Kang Taek
authors.initials: KT
authors.lastname: Lee
authors.forename: Taeghwan
authors.initials: T
authors.lastname: Hyeon
authors.forename: Yung Doug
authors.initials: YD
authors.lastname: Suh
mesh_terms: D003952:Diagnostic Imaging / Q000379:methods; D004705:Endocytosis; D005089:Exocytosis; D006367:HeLa Cells; D006801:Humans; D028581:Lanthanoid Series Elements / Q000737:chemistry*; D008163:Luminescent Measurements; D008856:Microscopy, Fluorescence; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure
chemical_list: D028581:Lanthanoid Series Elements