Lei Pengpeng, Liu Xiuling, Dong Lile, Wang Zhuo, Song Shuyan, Xu Xia, Su Yue, Feng Jing, Zhang Hongjie
State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, China.
Dalton Trans. 2016 Feb 14;45(6):2686-93. doi: 10.1039/c5dt04279h. Epub 2016 Jan 8.
Water-soluble lanthanide (Ln(3+)) doped Bi2O3 nanospheres have been successfully prepared through a solid-state-chemistry thermal decomposition process. The nanospheres exhibit intense upconversion luminescence (UCL) by doping the Ln(3+) (Ln = Yb, Er/Ho/Tm) ions into the Bi2O3 host matrix under 980 nm excitation. The ratio of red/green emission of Bi2O3:Yb(3+)/Er(3+) nanospheres exhibits a significant change as the calcination temperature increases and the value could reach 105.6. Moreover, the UCL of Bi2O3:Yb(3+)/Tm(3+) nanospheres are temperature-sensitive, where the intensity ratios of 799 and 808 nm emissions increase monotonously with temperature. The MTT assay reveals that Bi2O3:Yb(3+)/Tm(3+) nanospheres exhibit good biocompatibility by grafting citric acid molecules on the surface. The application possibility of Bi2O3:Yb(3+)/Tm(3+) nanospheres as bioprobes for optical imaging in vivo is also confirmed by the high-contrast photoluminescence images between the background and the UCL imaging area.
通过固态化学热分解过程成功制备了水溶性镧系元素（Ln(3+)）掺杂的Bi2O3纳米球。在980 nm激发下，通过将Ln(3+)（Ln = Yb、Er/Ho/Tm）离子掺杂到Bi2O3主体基质中，纳米球呈现出强烈的上转换发光（UCL）。随着煅烧温度升高，Bi2O3:Yb(3+)/Er(3+)纳米球的红/绿发射比发生显著变化，该值可达105.6。此外，Bi2O3:Yb(3+)/Tm(3+)纳米球的UCL对温度敏感，其中799和808 nm发射的强度比随温度单调增加。MTT分析表明，通过在表面接枝柠檬酸分子，Bi2O3:Yb(3+)/Tm(3+)纳米球表现出良好的生物相容性。背景与UCL成像区域之间的高对比度光致发光图像也证实了Bi2O3:Yb(3+)/Tm(3+)纳米球作为体内光学成像生物探针的应用可能性。
