Shandong Key Laboratory of Molecular Engineering, State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Shandong Academy of Sciences, Jinan, 250353, China.
Shandong Key Laboratory of Molecular Engineering, State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Shandong Academy of Sciences, Jinan, 250353, China.
Carbohydr Polym. 2020 Jun 1;237:116112. doi: 10.1016/j.carbpol.2020.116112. Epub 2020 Mar 4.
Chitosan has attracted much attention in drug delivery, however, carboxymethyl chitosan (CMC)-based self-aggregated nanocarriers are seldom reported. In this paper, two kinds of CMC-based pH-responsive amphiphilic chitosan derivatives, N-2-hydroxylpropyl-3-butyl ether-O-carboxymethyl chitosan (HBCC) and N-2-hydroxylpropyl-3-(2-ethylhexyl glycidyl ether)-O-carboxymethyl chitosan (H2ECC), have been synthesized by the homogeneous reaction. The molecular structures were characterized by FTIR, H NMR and C NMR. The optimum reaction condition was obtained based on the data of H NMR spectrum: reaction time of 4 h, reaction temperature of 80 °C and nn of 3/1, respectively. The XRD patterns showed the crystallinity of HBCC and H2ECC decreased due to the introduction of hydrophobic segments. The thermostability of HBCC and H2ECC was improved for the formation of heat-resistant stereo-complexed structures. The intermolecular hydrophobic interaction hindered the intermolecular mobility by increasing glass transition temperature of ca. 10 °C. Both HBCC and H2ECC have very low critical aggregation concentrations (HBCC: 0.66-1.56 g/L, H2ECC: 0.57-1.07 g/L) and moderate aggregate particle size, which is advantageous for utilization as a drug carrier. The curcumin loaded HBCC and H2ECC aggregates showed nontoxicity, meanwhile, HBCC and H2ECC showed good antibacterial activity against Staphylococcus aureus and Escherichia coli. As a result of these two favorable properties, HBCC and H2ECC could be used as curcumin nanocarriers as well as antibacterial agents.
壳聚糖在药物传递中引起了广泛关注，然而，基于羧甲基壳聚糖（CMC）的自聚集纳米载体却很少有报道。本文通过均相反应合成了两种基于 CMC 的 pH 响应性两亲性壳聚糖衍生物，N-2-羟丙基-3-丁基醚-O-羧甲基壳聚糖（HBCC）和 N-2-羟丙基-3-（2-乙基己基缩水甘油醚）-O-羧甲基壳聚糖（H2ECC）。通过 FTIR、H NMR 和 C NMR 对其分子结构进行了表征。根据 H NMR 谱的数据，得到了最佳反应条件：反应时间 4 h、反应温度 80°C、n n 分别为 3/1。XRD 图谱表明，由于引入了疏水性片段，HBCC 和 H2ECC 的结晶度降低。HBCC 和 H2ECC 的热稳定性提高，是因为形成了耐热的立体复合物结构。分子间的疏水相互作用通过增加约 10°C 的玻璃化转变温度来阻碍分子间的迁移。HBCC 和 H2ECC 的临界聚集浓度（HBCC：0.66-1.56 g/L，H2ECC：0.57-1.07 g/L）都非常低，聚集颗粒适中，有利于作为药物载体使用。载姜黄素的 HBCC 和 H2ECC 聚集物表现出低毒性，同时 HBCC 和 H2ECC 对金黄色葡萄球菌和大肠杆菌表现出良好的抗菌活性。由于这两个有利的特性，HBCC 和 H2ECC 可以用作姜黄素纳米载体和抗菌剂。
