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文獻(xiàn)名： Influence of 2-(diisopropylamino)ethyl methacrylate on acid-triggered hydrolysis of cyclic benzylidene acetals and their importance in efficient drug delivery

 

作者： Minjie Tang,a   Zheng Yang, a   Zujian Feng, a   Junhui Zhou, a   Jinjian Liu,b   Jianfeng Liu, b   Weiwei Wang,c   Junqiang Zhao, a   Anjie Dong a d and    Liandong Deng a  

a Department of Polymer Science and Technology and Key Laboratory of Systems Bioengineering of the Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China 

bTianjin Key Laboratory of Molecular Nuclear Medicine, Institute of Radiation Medicine, Chinese Academy of Medical Science and Peking Union Medical College, Tianjin, China

cTianjin Key Laboratory of Biomaterial Research, Institute of Biomedical Engineering, Chinese Academy of Medical Science and Peking Union Medical College, Tianjin 300192, China

dCollaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China

 

摘要：The ability to tune the degradation rate of a biodegradable polymer, which can achieve precise spatiotemporal control of drug delivery, is of considerable interest for biomedical applications. In this study, a series of amphiphilic copolymers, methoxy poly(ethyleneglycol)-b-poly((2,4,6-trimethoxybenzylidene-1,1,1-tris(hydroxymethyl) ethane methacrylate)-co-2-(diisopropylamino)ethyl methacrylate) (mPEG-b-P(TTMA-co-DPA), PETD) with different numbers of DPA units, were synthesized by Reversible Addition Fragmentation Chain Transfer (RAFT) copolymerization, in which DPA containing tertiary amines were introduced to adjust the hydrolysis behavior of cyclic benzylidene acetals (CBAs). The molecular structure and the chemical composition of PETD were characterized by 1H NMR and gel permeation chromatography (GPC). PETD could self-assemble into stable nanoparticles with well-defined spherical morphology and displayed high drug loading capacity with doxorubicin (DOX) as the drug model. The hydrolysis behavior of CBAs in the PETD NPs was investigated by UV/vis spectroscopy under different pH values. Compared with PETD-0 bearing no DPA unit, the hydrolysis rate of PETD-3 with more DPA was faster, while PETD-1 with less DPA hydrolyzed much slower, which indicated that the introduction of DPA had an amphoteric effect on the hydrolysis behavior of CBAs under acidic conditions. In addition, the in vitro release of DOX was also investigated under different pH conditions and the result was in accordance with the hydrolysis result. Furthermore, the results of fluorescence microscopy demonstrated improved internalization of DOX-loaded PETD-3 NPs in HepG-2 cells with rapid DOX release intracellularly, which showed considerable cytotoxicity against HepG-2 cells.