Original articles
Ji Li, Yitian Du, Haitao Su, Shixuan Cheng, Yanxia Zhou, Yiguang Jin, Xian-Rong Qi. Interfacial properties and micellization of triblock poly(ethylene glycol)-poly(ε-caprolactone)-polyethyleneimine copolymers[J]. Acta Pharmaceutica Sinica B, 2020, 10(6): 1122-1133

Interfacial properties and micellization of triblock poly(ethylene glycol)-poly(ε-caprolactone)-polyethyleneimine copolymers
Ji Lia, Yitian Dua, Haitao Sua, Shixuan Chenga, Yanxia Zhoua, Yiguang Jinb, Xian-Rong Qia
a Key Laboratory of Molecular Pharmaceutics and New Drug Delivery System, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China;
b Department of Pharmaceutical Sciences, Beijing Institute of Radiation Medicine, Beijing 100850, China
This study aimed to explore the link between block copolymers' interfacial properties and nanoscale carrier formation and found out the influence of length ratio on these characters to optimize drug delivery system. A library of diblock copolymers of PEG-PCL and triblock copolymers with additional PEI (PEG-PCL-PEI) were synthesized. Subsequently, a systematic isothermal investigation was performed to explore molecular arrangements of copolymers at air/water interface. Then, structural properties and drug encapsulation in self-assembly were investigated with DLS, SLS and TEM. We found the additional hydrogen bond in the PEG-PCL-PEI contributes to film stability upon the hydrophobic interaction compared with PEG-PCL. PEG-PCL-PEI assemble into smaller micelle-like (such as PEG-PCL4006-PEI) or particle-like structure (such as PEG-PCL8636-PEI) determined by their hydrophilic and hydrophobic block ratio. The distinct structural architectures of copolymer are consistent between interface and self-assembly. Despite the disparity of constituent ratio, we discovered the arrangement of both chains guarantees balanced hydrophilic-hydrophobic ratio in self-assembly to form stable construction. Meanwhile, the structural differences were found to have significant influence on model drugs incorporation including docetaxel and siRNA. Taken together, these findings indicate the correlation between molecular arrangement and self-assembly and inspire us to tune block compositions to achieve desired nanostructure and drug loading.
Key words:   
Received: 2019-07-04     Revised: 2019-10-24
DOI: 10.1016/j.apsb.2020.01.006
Funds: We would like to acknowledge the NSFC (Nos. 81673365, 81973258 and 81473156, China), and the Fangzheng Foundation (China) for funding of the work. The authors also thank Prof. Xinjing Tang from State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University (Beijing, China) for his kind support for copolymer synthesis.
Corresponding author: Yiguang Jin, Xian-Rong Qi     Email:jinyg@sina.com;qixr@bjmu.edu.cn
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