化学学报 ›› 2018, Vol. 76 ›› Issue (5): 393-399.DOI: 10.6023/A18010039 上一篇    下一篇

研究论文

Angiopep-2修饰的Ag2S量子点用于近红外二区脑胶质瘤成像

徐毅a,b, 赵彦b, 张叶俊c, 崔之芬b, 王丽华b, 樊春海b, 高基民a, 孙艳红b   

  1. a 温州医科大学 检验医学院、生命科学学院 温州 325000;
    b 中国科学院上海应用物理研究所 微观界面物理与探测重点实验室 物理生物学研究室 上海 201800;
    c 苏州影睿光学科技有限公司 苏州 215123
  • 收稿日期:2018-01-26 出版日期:2018-05-15 发布日期:2018-03-16
  • 通讯作者: 高基民,E-mail:jimingao64@163.com;孙艳红,E-mail:sunyanhong@sinap.ac.cn E-mail:jimingao64@163.com;sunyanhong@sinap.ac.cn
  • 基金资助:

    项目受国家自然科学基金(Nos.11575278,21675167,11675251,61475181,61378062)、国家重点研发计划(Nos.2016YFA0201200,2016YFA0400902)和中国科学院前沿科学重点研究(No.QYZDJ-SSW-SLH031-02)资助.

Angiopep-2-conjugated Ag2S Quantum Dot for NIR-II Imaging of Brain Tumors

Xu Yia,b, Zhao Yanb, Zhang Yejunc, Cui Zhifenb, Wang Lihuab, Fan Chunhaib, Gao Jimina, Sun Yanhongb   

  1. a School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou 325000;
    b CAS Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800;
    c Suzhou Near-Infrared Optics Technology Co., Ltd., Suzhou 215123
  • Received:2018-01-26 Online:2018-05-15 Published:2018-03-16
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Nos. 11575278, 21675167, 11675251, 61475181, 61378062), the Ministry of Science and Technology of China (Nos. 2016YFA0201200, 2016YFA0400902) and the Key Research Program of Frontier Sciences (No. QYZDJ-SSW-SLH031-02).

构建了一种近红外二区成像探针,能对脑部病变进行近红外二区荧光成像.利用脑靶向肽Angiopep-2对Ag2S量子点进行修饰,Ag2S量子点和Angiopep-2多肽经EDC和NHS介导,通过氨基和羧基的缩合反应进行连接,采用琼脂糖电泳、动态光散射及透射电镜等方法对材料进行表征,并观察了材料对脑胶质瘤细胞U87MG的细胞毒性、材料在该细胞中的分布、摄取以及在实体瘤荷瘤鼠中的分布情况.结果显示,Ag2S量子点水合粒径约为6 nm,经肽修饰后粒径约为8 nm,表面zeta电位正电性增强,在琼脂糖电泳中,肽修饰后Ag2S迁移距离较Ag2S短,表明Angiopep-2多肽修饰到了量子点上.经过细胞实验发现,修饰后的Ag2S量子点在100 μg/mL以下没有细胞毒性,脑胶质瘤U87MG细胞对Angiopep-2多肽修饰的Ag2S较Ag2S具有更高的摄取.经过初步的实体瘤动物实验发现,Angiopep-2修饰的Ag2S能在皮下瘤模型中出现分布和聚集,说明修饰后的Ag2S量子点具有一定脑胶质瘤细胞的靶向性.

关键词: 硫化银量子点, 脑靶向, Angiopep-2, 近红外二区成像

Ag2S quantum dot with excellent NIR-Ⅱ fluorescence can provide deeper tissue penetration (>1.1 cm) and higher spatiotemporal resolution (25 μm, 50 ms) in comparison to the conventional fluorophore. In this study, we designed a NIR-Ⅱ probe based Ag2S quantum dot for imaging of brain tumor. Angiopep-2 was used to modify Ag2S quantum dot, which is a 19-mer peptide exhibiting high binding efficiency with low-density lipoprotein receptor-related protein-1 (LRP-1) of blood brain barrier and glioma. Due to the surface of Ag2S quantum dots with carboxyl groups and angiopep-2 peptide with amino groups, Ag2S was conjugated with Angiopep-2 (Ag2S-ANG) through the condensation reaction of amino and carboxyl groups mediated by EDC and NHS. The structure, size and spectral properties of Ag2S-ANG were characterized by agarose electrophoresis, dynamic light scattering transmission, electron microscope (TEM), UV-vis spectrometer and NIR fluorescence spectrometer, respectively. Results showed that Ag2S-ANG had a short migration distance compared with Ag2S in the agarose gel electrophoresis. The hydrate particle size of Ag2S was approximately 6 nm, Ag2S-ANG was approximately 8 nm and its zeta potential exhibited electropositive reinforcement, zeta potential of Ag2S is -11.47±1.56 mV and Ag2S-ANG is +28.7±1.35 mV. Ag2S-ANG exhibited similar absorbance and fluorescence spectra to Ag2S, except a slight enhancement of emission peak. These results indicated that Ag2S-ANG was synthesized successfully. We further observed its cell cytotoxicity, distribution and uptake in Uppsala 87 Malignant Glioma cells(U87MG), and in vivo distribution in the solid tumor-bearing mouse. Ag2S-ANG had no obvious cytotoxicity when the concentration is inferior to 100 μg/mL and had more uptake in U87MG cells than that of Ag2S. In animal experiments, glioma tumor-bearing mice were used to investigate the distribution and tumor targeting of Ag2S-ANG. Results showed that Ag2S-ANG can distribute and accumulate in subcutaneous tumor site, indicating that Ag2S-ANG had the potential of targeting the glioma cells.

Key words: Ag2S quantum dot, brain-targeting, angiopep-2, NIR-II imaging References