Wang Hongcai, Chen Xiuqiong, Wen Yanshi, Li Dongze, Sun Xiuying, Liu Zhaowen, Yan Huiqiong, Lin Qiang
Key Laboratory of Tropical Medicinal Resource Chemistry of Ministry of Education, College of Chemistry and Chemical Engineering, Hainan Normal University, Haikou 571158, China.
Key Laboratory of Natural Polymer Functional Material of Haikou City, College of Chemistry and Chemical Engineering, Hainan Normal University, Haikou 571158, China.
Polymers (Basel). 2022 Apr 21;14(9):1679. doi: 10.3390/polym14091679.
Oxidized sodium alginate (OSA) is selected as an appropriate material to be extensively applied in regenerative medicine, 3D-printed/composite scaffolds, and tissue engineering for its excellent physicochemical properties and biodegradability. However, few literatures have systematically investigated the structure and properties of the resultant OSA and the effect of the oxidation degree (OD) of alginate on its biodegradability and gelation ability. Herein, we used NaIO as the oxidant to oxidize adjacent hydroxyl groups at the C-2 and C-3 positions on alginate uronic acid monomer to obtain OSA with various ODs. The structure and physicochemical properties of OSA were evaluated by Fourier transform infrared spectroscopy (FT-IR), H nuclear magnetic resonance (H NMR), X-ray Photoelectron Spectroscopy (XPS), X-ray Diffraction (XRD), and thermogravimetric analysis (TGA). At the same time, gel permeation chromatography (GPC) and a rheometer were used to determine the hydrogel-forming ability and biodegradation performance of OSA. The results showed that the two adjacent hydroxyl groups of alginate uronic acid units were successfully oxidized to form the aldehyde groups; as the amount of NaIO increased, the OD of OSA gradually increased, the molecular weight decreased, the gelation ability continued to weaken, and degradation performance obviously rose. It is shown that OSA with various ODs could be prepared by regulating the molar ratio of NaIO and sodium alginate (SA), which could greatly broaden the application of OSA-based hydrogel in tissue engineering, controlled drug release, 3D printing, and the biomedical field.
氧化海藻酸钠（OSA）因其优异的物理化学性质和生物降解性，被选为一种适用于再生医学、3D打印/复合支架和组织工程的材料。然而，很少有文献系统地研究所得OSA的结构和性能，以及海藻酸钠氧化度（OD）对其生物降解性和凝胶化能力的影响。在此，我们使用NaIO作为氧化剂，氧化海藻酸醛酸单体C-2和C-3位上相邻的羟基，以获得具有不同OD的OSA。通过傅里叶变换红外光谱（FT-IR）、氢核磁共振（H NMR）、X射线光电子能谱（XPS）、X射线衍射（XRD）和热重分析（TGA）对OSA的结构和物理化学性质进行了评估。同时，使用凝胶渗透色谱（GPC）和流变仪来测定OSA的水凝胶形成能力和生物降解性能。结果表明，海藻酸醛酸单元的两个相邻羟基成功氧化形成醛基；随着NaIO用量的增加，OSA的OD逐渐增大，分子量减小，凝胶化能力持续减弱，降解性能明显提高。结果表明，通过调节NaIO与海藻酸钠（SA）的摩尔比，可以制备出具有不同OD的OSA，这可以大大拓宽基于OSA的水凝胶在组织工程、控释药物、3D打印和生物医学领域的应用。
