光动力疗法（PDT）以其毒性小、疗效快、靶向性强等优点成为肿瘤治疗的重要方法，如何发现合适的光敏剂是该疗法的关键。传统中药成分姜黄素（Cur）是目前研究的热点光敏剂之一，课题组的前期工作研究了姜黄素固体脂质纳米粒（Cur-SLN）的制备、表征和光动力机理，发现Cur-SLN是一种非常优秀的光敏剂。但该体系只能在组织穿透力差的450nm蓝光激发。为了克服这些缺点，本课题组拟将上转换发光纳米材料引入Cur-SLN内部，同时将叶酸等肿瘤靶向分子连接到纳米颗粒表面，构成一个能被穿透力强的980nm红外光高效激发，且具有肿瘤靶向性PDT纳米载药的新剂型。在细胞和动物水平上评价新剂型的安全性和抗肿瘤效果，探讨上转换的特性、效率与抗肿瘤细胞增殖的机制，为寻找具有新的PDT候选光敏剂及剂型提供理论依据，获得一种高效、安全用于肿瘤光动力治疗的姜黄素新剂型，并建立一套用于PDT载药体系筛选和研究的平台。

Photodynamic therapy has become an important method for cancer treatment due to low-toxicity, rapid efficacy, strong targeting ability etc. It is a key point to find a suitable photosensitizer for this therapy. Curcumin (Cur), the composition of the traditional Chinese medicine, is one of the hot photosensitizers on research at present. Our previous studies, including the preparation of Cur-loaded solid lipid nanoparticles (Cur-SLN), its characterization, and its mechanism of the photo-toxicity to tumor cells, indicated that Cur-SLN is an excellent photosensitizer. But it was only excitated by blue light (λ= 450 nm) with a poor tissue penetration. Besides, it lacks the tumor targeting. In order to overcome these shortcomings, we plan to incorporate upconversion luminescent nanoparticles (UCNPs) into Cur-SLN, as well as graft the tumor targeting molecules such as folic acid to the surface of nanoparticles, so that constitute a new PDT drug nano-carrier system with a powerful tissue penetration (λex= 980 nm) and a high tumor targeted property. Furthermore, we will evaluate its security and anti-tumor effects in vitro and in vivo. Additionally, it is essential to discuss the characteristics and efficiency of its upconversion, as well as the mechanism of its inhibition on the proliferation of tumor cells. All together, these experiments would provide theoretical basis for looking for new PDT photosensitizer candidates and its formulations. Meanwhile, we would obtain a new kind of efficient and safe formulations of Cur that can be applied for the photodynamic therapy of cancer. Besides, we also would establish a new platform that can be used to screen and research PDT drug carrier system.