Abstract：
Local drug delivery has generated considerable interest due to its controlled and sustained drug release at the target site on demand. Nanoaggregate-incorporated composite hydrogels are desirable as local drug delivery systems; however, it is difficult to achieve sustained and controlled hydrophobic drug release and superior mechanical properties in one system. Herein, a \"smart\" composite hydrogel was synthesized by incorporating hemicellulose-based nanoaggregates into a double network consisting of alginate/Ca2+ and polyacrylic acid-co-dimethylaminoethyl methacrylate [P(AA-co-DMAEMA)]. Hemicellulose-based nanoaggregates were assembled from xylan-rich hemicellulose laurate methacrylate (XH-LA-MA) polymers and entrapped into the hydrogel framework via chemical fixation. Another composite hydrogel with physically embedded hemicellulose laurate (XH-LA) nanoaggregates was prepared as a comparison. Accordingly, covalently cross-linked XH-LA-MA nanoaggregates in hydrogels resulted in a denser pore structure and reinforced mechanical properties. Nanoaggregate diffusion analysis revealed that covalent bonding between the nanoaggregates and the hydrogel framework contributed to prolonged diffusion behavior. Curcumin (Cur)-loaded XH-LA-MA composite hydrogels enabled sustained Cur release in simulated body fluid and showed stimulus responsiveness toward ethylenediaminetetraacetic acid (EDTA) and/or glutathione (GSH). All the composite hydrogels were biocompatible, as verified by Cell Counting Kit-8 (CCK-8) assay against NIH/3T3 cells. These composite hydrogels hold great potential as a promising dosage form for biomedical applications.
摘要：
局部药物递送由于其在靶位点的受控和持续的药物释放而产生了相当大的兴趣。掺入纳米聚集体的复合水凝胶作为局部药物递送系统是可取的;然而,很难在一个系统中实现持续和受控的疏水药物释放和优异的机械性能。在这里，通过将半纤维素基纳米聚集体掺入由藻酸盐/Ca2+和聚丙烯酸-共聚-甲基丙烯酸二甲基氨基乙酯[P(AA-co-DMAEMA)]组成的双网络中，合成了“智能”复合水凝胶。半纤维素基纳米聚集体由富含木聚糖的半纤维素月桂酸酯甲基丙烯酸酯(XH-LA-MA)聚合物组装,并通过化学固定包埋在水凝胶框架中。制备具有物理包埋的半纤维素月桂酸酯(XH-LA)纳米聚集体的另一种复合水凝胶作为对比。因此，水凝胶中共价交联的XH-LA-MA纳米聚集体导致更致密的孔结构和增强的机械性能。纳米聚集体扩散分析揭示纳米聚集体与水凝胶骨架之间的共价键合有助于延长的扩散行为。负载姜黄素（Cur）的XH-LA-MA复合水凝胶可在模拟体液中持续释放Cur，并显示出对乙二胺四乙酸（EDTA）和/或谷胱甘肽（GSH）的刺激反应。所有的复合水凝胶都是生物相容的，如通过针对NIH/3T3细胞的细胞计数试剂盒-8(CCK-8)测定所验证。这些复合水凝胶作为生物医学应用的有希望的剂型具有巨大的潜力。
