Controlled long-term sustained release of poly(lactic acid) composite microspheres with dual-responsive cellulose nanocrystals
作者：Mingxin Wang, Somia, Ruixin Gong, Haibin Ji, Ying Zhou, Hou-Yong Yu, et al.
關鍵字：polymer microspheres, cellulose nanocrystals
論文來源：期刊
具體來源：DOI: 10.1039/D3CE00440F
發表時間：2023年
Recently, polymer composite microspheres have attracted substantial concerns due to excellent biodegradable and long-controlled-release characteristics. However, it remains a major challenge to produce polymer microspheres with controlled properties and customizable drug release. To achieve controlled long-term sustained release, polylactide composite microspheres (PLA-C) with dual-responsive cellulose nanocrystals(C-PMA) were engineered by radical polymerization and double emulsion(W/O/W) solvent evaporation. The C-PMA nanoparticles are obtained by grafting Poly[2-(N,N-dimethyl amino) ethyl methacrylate](PDMAEMA)onto cellulose nanocrystals (CNC), which not only possess the advantages of CNC but also inherit the excellent temperature and pH responsiveness of PDMAEMA, and used as a dual functional nano reinforcement in polylactic acid microspheres.As expected, 5wt% C-PMA enhanced the crystallization and hydrophilic properties of PLA-C microspheres.Furthermore, the incorporation of dual-responsive C-PMA nanoparticles, controlled and long-term sustained release behavior of composite microspheres could be achieved.The cumulative release profiles of PLA-C20 composite microspheres loaded with tetracycline hydrochloride(TCH) exhibited low levels of drug release at pH=7.4 and 8, while at lower pH (5.0) and higher temperatures (43°C), the drug release rate was significantly accelerated, and the cumulative drug release rate reached 82%, demonstrating a temperature and pH dual-responsive controlled drug release capability of the composite microspheres. Moreover, the four drug release models are presented to demonstrate different drug release mechanisms of dual-responsive PLA-C microspheres, which indicate the dual-responsive PLA-C composite microspheres with potential multifunctional drug delivery systems for promising medical applications.