Multi-functional NaErF4:Yb nanorods: enhanced red upconversion emission, in vitro cell, in vivo X-ray, and T2-weighted magnetic resonance imaging.
In this paper, multi-functional hexagonal phase NaErF4:Yb nanorods were synthesized by a facile hydrothermal method. The upconversion luminescence (UCL) intensity and red to green ratio of the multi-functional NaErF4 nanorods can be improved by Yb(3+) doping. More importantly, owing to the decreased distance of Er and Yb, the significant enhancement of red UCL can be obtained, which is different to the usual green UCL of Yb/Er doped NaYF4 host. In addition, the intensity of UCL is strongest when the Yb(3+)-doped concentration reached 30%. The in vitro cell imaging and localized UCL spectra taken from HeLa cells revealed that these NaErF4: 30% Yb(3+) nanorods are ideal nanoprobes with absence of autofluorescence for optical bioimaging. Moreover, these nanorods possess large X-ray absorption ions (Er(3+) and doped Yb(3+)), and were successfully used as contrast agents for in vivo X-ray bioimaging for the first time. In addition to the excellent UCL and X-ray absorption properties, these nanorods present significant paramagnetic properties and can be used as T2-weighted magnetic resonance imaging (MRI) agents. Therefore, these enhanced red UCL NaErF4 nanocrystals with excellent paramagnetic properties and X-ray absorption properties can be used as promising multi-modal nanoprobes for optical bioimaging, MRI, computed X-ray tomography (CT), and may have potential applications in bioseparation.
College of Physics and Information Science, Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of the Ministry of Education, Hunan Normal University, Changsha, Hunan, China. songjunz@hunnu.edu.cn.
Haibo
H
Wang
Wei
W
Lu
Tianmei
T
Zeng
Zhigao
Z
Yi
Ling
L
Rao
Hongrong
H
Liu
Songjun
S
Zeng
D000818:Animals; D003287:Contrast Media / Q000737:chemistry*; D004871:Erbium / Q000737:chemistry*; D005459:Fluorides / Q000737:chemistry*; D006367:HeLa Cells; D006801:Humans; D008279:Magnetic Resonance Imaging; D051379:Mice; D018613:Microscopy, Confocal; D043942:Nanotubes / Q000737:chemistry*; D011859:Radiography; D012867:Skin / Q000000981:diagnostic imaging
D003287:Contrast Media; D004871:Erbium; D005459:Fluorides