摘要
不同二价金属离子交联剂与海藻酸钠具有不同交联机制,可形成结构与性能具有显著差异的海藻酸盐凝胶。价键理论分析结果表明,Ca2+、Zn2+、Ba2+三种金属离子与海藻酸钠分子分别以dsp2、sp3、sp3d2方式配位杂化,形成平面正方形、正四面体和正八面体构型。采用扫描电子显微镜、电感耦合全谱等离子体发射光谱仪和热失重分析仪等表征金属离子交联凝胶的微观形貌、金属含量、热稳定性等与结构的相关性。以牛血清白蛋白(Mw=67 kDa)为模型,考察了三种交联凝胶的结构对其扩散传递行为的影响。在此基础上,对三种金属离子交联凝胶与壳聚糖(Mw=100kDa)扩散反应成膜行为进行了考察。结果表明,Ca2+、Zn2+、Ba2+与海藻酸钠交联后,凝胶中结合的金属元素含量依次增加,凝胶结构趋于致密且热稳定性增加,对牛血清白蛋白分子的扩散阻力依次增大,致密的凝胶结构有利于壳聚糖在凝胶表面形成稳定连续的膜层。
Alginate gels（SA） with different structure and properties can be formed when crosslinking with different divalent metal ions. The hybrid orbital theory indicates that Ba2＋, Zn2＋, Ca2＋ coordinate with SA via sp3 d2, sp3 and dsp2 and form octahedron, tetrahedron and planar square configurations, respectively. Micromorphology, metal contents and thermal stability of different metal ion crosslinked gels were characterized by scanning electron microscopy（SEM）, inductively coupled plasma-optical emission spectrometer（ICP） and thermogravimetic analysis（TGA）. Bovine serum albumin（BSA, Mw = 67 kDa） was selected as a model protein to investigate diffusion behaviors of molecule in alginate gels. Moreover, membrane formation between alginate gels and chitosan（CS, Mw = 100 kDa） was discussed. The results show that structure density, thermal stability and BSA diffusion resistance increase in an order of Ca2＋, Zn2＋, Ba2＋. In addition, crosslinking also helps to form continuous membranes.
作者
徐佳桐
温惠云
黄赛朋
潘士印
刘先宁
许宁侠
贾朝
薛伟明
XU Jia-tong;WEN Hui-yun;HUANG Sai-peng;PAN Shi-yin;LIU Xian-ning;XU Ning-xia;JIA Zhao;XUE Wei-ming(College of Chemical Engineering,Northwest University,Xi＇an 710069,China;Shaanxi Institute of Ophthalmology,Xi＇an 710002,China;Medical College,Xi＇an International University,Xi＇an 710077,China;College of Biology Pharmacy and Food Engineering,Shangluo University,Shangluo 726000,China)
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
2018年第5期1194-1202,共9页
Journal of Chemical Engineering of Chinese Universities
基金
陕西省自然科学基金(2015JM2044
2014JQ2067)
陕西省教育厅专项科研计划项目(16JK1770)
关键词
海藻酸盐
金属离子交联剂
杂化轨道
凝胶结构
扩散
alginate
metal ion crosslinkers
hybrid orbital
hydrogel structure
diffusion
