Acta Chim. Sinica ›› 2016, Vol. 74 ›› Issue (3): 234-240.DOI: 10.6023/A15120787 Previous Articles     Next Articles



赵文静a, 乔增莹b, 段中余a, 王浩b   

  1. a. 河北工业大学 化工学院 天津 300130;
    b. 国家纳米科学中心 纳米科学卓越创新中心 纳米生物效应与安全性重点实验室 北京 100190
  • 投稿日期:2015-12-19 发布日期:2016-02-23
  • 通讯作者: 段中余, 王浩;
  • 基金资助:

    项目受国家自然科学基金(Nos. 21374026, 51373046, 51473045)和河北省自然科学基金(B2014202209)资助.

Synthesis and Self-assembly of pH and ROS Dual Responsive Poly(β-thioester)s

Zhao Wenjinga, Qiao Zengyingb, Duan Zhongyua, Wang Haob   

  1. a School of Chemical Engineering, Hebei University of Technology, Tianjin 300130;
    b CAS Center for Excellence in Nanoscience, CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology (NCNST), Beijing 100190
  • Received:2015-12-19 Published:2016-02-23
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Nos. 21374026, 51373046, 51473045) and Hebei Provincial Natural Science Foundation of China (B2014202209).

The Michael addition reaction, which is a mild reaction between activated olefins and nucleophiles, has been widely used in synthesis of tailored macromolecular architectures. We designed a copolymer nanoparticle to obtain the ROS and pH dual responsive capability. We synthesized the amphiphilic poly(β-thioester)s copolymers (D-D-P) composed of di(ethylene glycol) diacrylate (DEDA), DL-dithiothreitol (DTT), acryloyl chloride (AC) and hydrophilic PEG-SH with average Mn=2000 g·mol-1 via Michael addition reaction. The reactions are facile and controllable, and the structures of acquired copolymers are well characterized. The structures of the polymers were confirmed by 1H NMR, and the number molecular weight and distribution of the copolymer D-D-P was measured by GPC (Mn=50400). D-D-P could self-assemble into nanoparticles with core-shell structures by dialysis method due to the composition of hydrophilic side chains and hydrophobic polymer backbones. After the preparation of ROS and pH dual responsive D-D-P nanoparticles in phosphate buffer solution, the morphology and size of D-D-P nanoparticles were observed by transmission electron microscopy (TEM) and dynamic light scattering (DLS) showed that the number size distribution of nanoparticles was around 280 nm. Nile Red (NR) is a unique neutral hydrophobic molecule, which shows very weak fluorescence in aqueous solution and can emit strong fluorescence in the hydrophobic environment. NR absorption and emission spectra are strongly dependent on environment polarity, which make it as a probe molecule that is widely used in the evaluation of microenvironment polarity. The disassembly behaviors of D-D-P nanoparticles were investigated by the change of the nanoparticle size and NR fluorescence spectra. The diameter of nanoparticle decreased under pH 5 and ROS environment conditions, and the NR fluorescence also became weak under pH 5 and ROS environment conditions, which could be attributed to the gradual dissociation of nanoparticles, proving the ROS and pH dual responsive properties of the poly(β-thioester)s. The release behaviors of the DOX encapsulated D-D-P nanoparticles in acidic and oxidative condition were studied by the UV absorption and were further proved in MCF-7 cells.

Key words: poly(β-thioester)s, nanoparticles, pH-responsive, ROS-responsive, self-assembly