title: Rare-Earth nanoparticles with enhanced upconversion emission and suppressed rare-Earth-ion leakage.
abstract: Upconversion emissions from rare-earth nanoparticles have attracted much interest as potential biolabels, for which small particle size and high emission intensity are both desired. Herein we report a facile way to achieve NaYF(4):Yb,Er@CaF(2) nanoparticles (NPs) with a small size (10-13 nm) and highly enhanced (ca. 300 times) upconversion emission compared with the pristine NPs. The CaF(2) shell protects the rare-earth ions from leaking, when the nanoparticles are exposed to buffer solution, and ensures biological safety for the potential bioprobe applications. With the upconversion emission from NaYF(4):Yb,Er@CaF(2) NPs, HeLa cells were imaged with low background interference.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Peking University, PR China.
authors.forename: Ye-Fu
authors.initials: YF
authors.lastname: Wang
authors.forename: Ling-Dong
authors.initials: LD
authors.lastname: Sun
authors.forename: Jia-Wen
authors.initials: JW
authors.lastname: Xiao
authors.forename: Wei
authors.initials: W
authors.lastname: Feng
authors.forename: Jia-Cai
authors.initials: JC
authors.lastname: Zhou
authors.forename: Jie
authors.initials: J
authors.lastname: Shen
authors.forename: Chun-Hua
authors.initials: CH
authors.lastname: Yan
mesh_terms: D006367:HeLa Cells; D006801:Humans; D007477:Ions / Q000737:chemistry*; D049408:Luminescent Agents / Q000032:analysis* / Q000737:chemistry; D008163:Luminescent Measurements; D008674:Metals, Rare Earth / Q000032:analysis* / Q000737:chemistry; D018613:Microscopy, Confocal; D053758:Nanoparticles / Q000032:analysis* / Q000737:chemistry / Q000648:ultrastructure; D010316:Particle Size
chemical_list: D007477:Ions; D049408:Luminescent Agents; D008674:Metals, Rare Earth