Department of Chemistry & Institutes of Biomedical Sciences, Fudan University, Shanghai 200433, PR China.
Chem Soc Rev. 2012 Feb 7;41(3):1323-49. doi: 10.1039/c1cs15187h. Epub 2011 Oct 19.
Rare-earth upconversion nanophosphors (UCNPs), when excited by continuous-wave near-infrared light, exhibit a unique narrow photoluminescence with higher energy. Such special upconversion luminescence makes UCNPs promising as bioimaging probes with attractive features, such as no auto-fluorescence from biological samples and a large penetration depth. As a result, UCNPs have emerged as novel imaging agents for small animals. In this critical review, recent reports regarding the synthesis of water-soluble UCNPs and their surface modification and bioconjugation chemistry are summarized. The applications of UCNPs for small-animal imaging, including tumor-targeted imaging, lymphatic imaging, vascular imaging and cell tracking are reviewed in detail. The exploration of UCNPs as multifunctional nanoscale carriers for integrated imaging and therapy is also presented. The biodistribution and toxicology of UCNPs are further described. Finally, we discuss the challenges and opportunities in the development of UCNP-based nanoplatforms for small-animal imaging (276 references).
稀土上转换纳米荧光粉（UCNPs）在连续波近红外光激发下，表现出独特的窄光致发光，具有更高的能量。这种特殊的上转换发光使 UCNPs 有望成为生物成像探针，具有吸引人的特点，如生物样品无自发荧光和较大的穿透深度。因此，UCNPs 已成为小动物成像的新型造影剂。在这篇重要综述中，总结了最近关于水溶性 UCNPs 的合成及其表面修饰和生物缀合化学的报道。详细综述了 UCNPs 在小动物成像中的应用，包括肿瘤靶向成像、淋巴成像、血管成像和细胞跟踪。还介绍了 UCNPs 作为多功能纳米级载体用于集成成像和治疗的探索。进一步描述了 UCNPs 的生物分布和毒理学。最后，我们讨论了基于 UCNP 的纳米平台在小动物成像方面的发展所面临的挑战和机遇（276 篇参考文献）。
