Enhanced red emission from GdF3:Yb3+,Er3+ upconversion nanocrystals by Li+ doping and their application for bioimaging.
Under 980 nm near-infrared (NIR) excitation, upconversion luminescent (UCL) emission of GdF(3):Yb,Er upconversion nanoparticles (UCNPs) synthesized by a simple and green hydrothermal process can be tuned from yellow to red by varying the concentration of dopant Li(+) ions. A possible mechanism for enhanced red upconverted radiation is proposed. A layer of silica was coated onto the surface of GdF(3):Yb,Er,Li UCNPs to improve their biocompatibility. The silica-coated GdF(3):Yb,Er,Li UCNPs show great advantages in cell labeling and in vivo optical imaging. Moreover, GdF(3) UCNPs also exhibited a positive contrast effect in T(1)-weighted magnetic resonance imaging (MRI). These results suggest that the GdF(3) UCNPs could act as dual-modality biolabels for optical imaging and MRI.
Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, PR China.
Wenyan
W
Yin
Lina
L
Zhao
Liangjun
L
Zhou
Zhanjun
Z
Gu
Xiaoxiao
X
Liu
Gan
G
Tian
Shan
S
Jin
Liang
L
Yan
Wenlu
W
Ren
Gengmei
G
Xing
Yuliang
Y
Zhao
D003952:Diagnostic Imaging / Q000379:methods; D005682:Gadolinium / Q000737:chemistry*; D008094:Lithium / Q000737:chemistry*; D049449:Luminescence; D008279:Magnetic Resonance Imaging; D053758:Nanoparticles / Q000737:chemistry; D019265:Spectroscopy, Near-Infrared / Q000379:methods; D015018:Ytterbium / Q000737:chemistry*; D015019:Yttrium / Q000737:chemistry*
D015019:Yttrium; D008094:Lithium; D005682:Gadolinium; D015018:Ytterbium