上转换发光纳米材料在生物成像领域的应用及进展

Applications of upconversion nanoparticles in bioimaging

上转换发光（UCL）是用低能量光激发出高能量光的过程，由于其所需激发光能量低、无自发荧光干扰、无光漂白且物理化学性质稳定，近年来广泛应用于生物成像。将基于上转换纳米粒子（UCNP）制得的显像剂，应用于UCL、CT、MR、PET等多模态显像中，可获得高信噪比的清晰图像。本文主要对UCNP在生物成像方面的应用作一综述。

Upconversion luminescence （UCL） is a process during which low-energy light was converted （excitation） to high-energy light. Due to the characteristics of low excitation power density, negligible autofluorescence, lack of photobleaching and high stability, UCL has been increasingly applied for bioimaging. Using the upconversion nanoparticles （UCNP） as agents in multimodality molecular imaging （UCL imaging, CT, MR, PET, etc）, we could obtain clear images with high signal to noise ratio. This review summarizes the applications of UCNP in the field of bioimaging.