中国科学院深圳先进技术研究院生物医药与技术研究所（筹）蔡林涛研究员带领的纳米医学研究小组近期在癌症诊断技术研究上取得重要进展。
在癌症诊断的研究中，近红外荧光纳米检测技术可以实现癌症原位、实时、靶向的无损监测。吲哚菁绿（ICG）是一种具有近红外特征吸收峰的三碳花菁染料，是唯一一种被美国食品药品监督管理局（FDA）批准的可用于临床诊断的近红外荧光染料。但是ICG的稳定性很差，在极性溶剂中会迅速聚集并分解，且在光照环境下会加速分解，这给储存和应用带来了困难。同时，ICG在水溶液中的不稳定性及在血浆中的快速清除率限制了它在荧光成像、目标组织定位方面的应用。
蔡林涛课题组以ICG为荧光材料，聚合物磷脂纳米颗粒为载体，叶酸为靶向分子，通过纳米沉淀与自组装的一步合成法成功开发了一种荧光性能稳定且对乳腺癌肿瘤细胞具有特异识别功能的近红外荧光纳米探针。研究表明，通过裸鼠尾静脉注射ICG纳米探针能够靶向识别肿瘤且在体内的循环时间显著长于游离ICG，表明该纳米探针可用于肿瘤实时检测，为肿瘤的早期诊断和药物递送系统的研究奠定了基础。
相关成果发表在近期出版的Biomaterials上。（生物谷Bioon.com）
doi:10.1016/j.biomaterials.2012.04.044
PMC:
PMID:
Indocyanine green-loaded biodegradable tumor targeting nanoprobes for in vitro and in vivo imaging
Cuifang Zhenga, Mingbin Zhenga, b, Ping Gonga, Dongxue Jiaa, Pengfei Zhanga, Bihua Shia, Zonghai Shenga, Yifan Maa, Lintao Caia, ,
Indocyanine green (ICG) is a near-infrared (NIR) fluorescence dye for extensive biological application, but limited by its poor aqueous stability in vitro, concentration-dependent aggregation, rapid elimination from the body, and lack of target specificity. In this paper, to overcome these limitations, folate receptor-targeted, ICG dye-doped poly(d,l-lactide-co-glycolide) (PLGA) lipid nanoparticles (FA-ICG-PLGA-lipid NPs) were constructed by a single-step self-assemble and nanoprecipitation method. The prepared FA-ICG-PLGA-lipid NPs exhibited good biocompatibility, monodispersity, excellent NIR penetration ability, significant stability against photobleaching and long circulation time. The intracellular uptake experiment proved the targeting efficacy of the FA-ICG-PLGA-lipid NPs was more effective in folate receptor over-expressing MCF-7 cells than folate receptor negative A549 cells. Furthermore, the in vivo experiments showed the FA-ICG-PLGA-lipid NPs were specifically targeted to the tumor, and its circulation time was much longer than free ICG. These biocompatible and biodegradable NIR-NPs prove a potential application in tumor diagnosis and targeted imaging due to its high aqueous stability, excellent NIR optical properties and significantly targeting property in vivo
