上转换纳米材料在生物应用中的研究进展

上转换发光纳米材料(UCNPs)具有荧光寿命长、潜在生物毒性低、穿透深度大、对生物组织损伤小且几乎没有背景光等显著优点,近年来,在光动力治疗(PDT)、生物成像及生物检测等领域已经得到广泛应用.但在应用的过程中存在一些缺陷,如在PDT中UCNPs与光敏剂之间能量转移效率较低、正常组织过热;在生物成像中,荧光强度较弱、光敏剂和激活剂有能量回流、成像模式单一等问题.科研人员针对上述问题研究出了很多解决的方法,如缩短UCNPs与目标物之间的距离、改变照射激光的强度、改变UCNPs的结构、将UCNPs作为新型多功能平台整合成像与治疗于一体等,使部分问题得到了很好的解决.本文重点综述了UCNPs应用在PDT和生物成像中所出现的问题及解决方法,并对UCNPs在生物医学领域的应用发展趋势进行展望.

The Development and Application of Up-conversion Nanomaterials in Biomedical

Upconversion luminescent nanomaterials have the significant advantages of long fluorescence lifetime, low potential biotoxicity, large penetration depth, small damage to biological tissues and few background light. In recent years, photodynamic therapy, bioimaging and biological detection have been widely used, but in the process of application, there are some problems such as low efficiency of energy transfer between UCNPs and target, overheating of normal tissues. In biological imaging, the fluorescence intensity is weak, the photosensitizer and activator have energy reflow, and the imaging mode is single. Researchers have developed a lot of solutions to these problems, such as shortening the distance between UCNPs and targets, changing the intensity of laser irradiation and the structure of UCPs, integrating UCNPs as a new multifunctional platform for imaging and treatment, etc., so that some of the problems are well solved. This review focuses on the solutions to the problems that arised from the use of UCNPs in PDT and bioimaging. The future development of UCNPs in biomedicine is also discussed.