目的制备一种水溶性稀土上转换荧光纳米探针NaYF4∶Yb3+/Er3+,用于动物活体荧光成像。方法采用三氟乙酸盐热分解法合成油溶性稀土上转换荧光纳米探针NaYF4∶Yb3+/Er3+,然后选用柠檬酸或L-半胱氨酸作为修饰剂,置于油-水两相中加热到100℃进行配体交换,离心纯化得到水溶性产物。并对所制备的上转换荧光纳米微粒进行X射线衍射测试(XRD)、X射线光电子能谱分析(XPS)、透射电子显微镜及红外和荧光光谱等表征,确定稀土上转换荧光纳米探针的组成、形态及修饰后该纳米探针的性质。最后将修饰后的水溶性稀土上转换荧光纳米探针作为探针应用于小鼠的活体成像。结果制备的稀土上转换荧光纳米探针NaYF4∶Yb3+/Er3+为立方相、平均粒径约21.3 nm的多边形结构,分别在540 nm和660 nm处发出荧光。用柠檬酸或L-半胱氨酸修饰后的稀土上转换荧光纳米探针可以稳定地分散在水中;并且修饰后的稀土上转换荧光纳米探针的粒径、晶相及荧光性质没有发生改变;红外光谱表明,该纳米探针的表面成功引入了修饰剂;该荧光纳米探针用于小鼠活体成像荧光信号清晰可见。结论研制出了一种用柠檬酸或L-半胱氨酸表面修饰的、水溶性稀土上转换荧光纳米探针NaYF4∶Yb3+/Er3+,表现出了较好的动物活体成像应用前景。 Aim To prepare NaYF4: Yb3 + / Er3 +, a water-soluble rare earth up-converting fluorescent probe for in vivo fluorescence imaging. Methods NaYF4: Yb3 + / Er3 +, an oil-soluble rare earth up-converting fluorescent probe, was synthesized by thermal decomposition of trifluoroacetate. Then, citric acid or L-cysteine ​​was used as a modifier to heat oil- Ligand exchange was carried out at 100 ° C to obtain water-soluble product by centrifugal purification. The prepared up-conversion fluorescent nanoparticles were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy and infrared and fluorescence spectroscopy to determine the composition of the rare earth up-conversion fluorescent nano-probes , Morphology and properties of the modified nano-probe. Finally, the modified water-soluble rare earth up-converting fluorescent nano-probe was used as a probe for in vivo imaging of mice. Results The rare earth up-conversion fluorescent probe NaYF4: Yb3 + / Er3 + was cubic with a mean diameter of about 21.3 nm. The fluorescence was detected at 540 nm and 660 nm, respectively. The rare earth up-converting fluorescent nano-probes modified with citric acid or L-cysteine ​​can be stably dispersed in water, and the particle size, crystal phase and fluorescence property of the modified rare earth up-converting fluorescent nano-probe have not changed ; Infrared spectroscopy showed that the surface of the nano-probe was successfully introduced into the modifier; the fluorescent nano-probe was used to clearly visualize the fluorescence signal of mouse live imaging. Conclusions A kind of NaYF4: Yb3 + / Er3 +, a kind of water-soluble rare earth up-conversion luminescent nano-probe modified with citric acid or L-cysteine, has been developed, which has shown a promising prospect in animal biopsy.