Nano-structure of octenyl succinic anhydride modified starch micelle
Nano-structure of octenyl succinic anhydride modified starch micelle
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DOI：
10.1016/j.foodhyd.2012.11.033
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发表时间：
2013-07
影响因子：
10.7
通讯作者：
Jie Zhu;Lin Li;Ling Chen;Xiaoxi Li
中科院分区：
文献类型：
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作者：
Jie Zhu;Lin Li;Ling Chen;Xiaoxi Li
研究了不同重均相对分子质量的辛烯基丁二酸酐(OSA-淀粉)变性淀粉在水溶液中的胶束纳米结构。用广义间接傅立叶变换(GIFT)对距离分布函数p(R)计算的胶束聚集观察、最大尺寸(Rmax)和小角X射线散射数据的Guinier拟合得到的回转半径(Rg)表明，不同OSA-淀粉来源的胶束存在明显的几何差异。胶束在浓度较高的水溶液中表现出较高的单分散性。相对分子质量最高的OSA-淀粉分子形成的胶束最大。相对分子质量最大的胶束动态光散射的流体动力学半径(Rh)有较大幅度的减小(从80 nm减小到46 nm)，Rg/Rh随浓度的增加变化更加明显，说明相对分子质量较大的胶束构象更灵活，对粒子间的静电斥力更敏感。相对分子质量最高的胶束内部结构最致密。P(R)图显示了由小亚单位的扁椭球、有限截面尺寸的长棒和扁平的长椭球所产生的典型轮廓。可以预见，这些纳米结构的差异可能与应用于水包油体系的OSA-淀粉的稳定性和其他性质密切相关。
The micelle nano-structures of octenyl succinic anhydride (OSA-starch) modified starches with different Mw(weight average molecular mass) in aqueous solution were studied. The micelle aggregates observation, maximum dimension (rmax) calculated from Pair Distance Distribution Function p(r) using General Indirect Fourier Transformation (GIFT) and radius of gyration (Rg) obtained from Guinier fitting of the small angle X-ray scattering data indicated the obvious geometric disparity of micelles originated from different OSA-starches. The micelle presented increased monodispersity in more concentrated aqueous solution. The OSA-starch molecules with the highest Mwformed the largest micelle. Hydrodynamic radius (Rh) via dynamic light scattering of the micelle with the highest Mwdecreased in larger extent (from 80 nm to 46 nm), as well as more distinct change of Rg/Rhwith increasing concentration, from which it could be deduced that the micelle conformation with higher Mwwas more flexible and more sensitive to the interparticle electrostatic repulsion. Moreover, the most compact interior structure formed within the micelle with the highest Mw. The p(r) plots show typical profiles yielded from some oblate ellipsoid with a small subunit, long rod with a limited cross-section dimension and flattened prolate ellipsoid. It is anticipated that these nano-structures differences could be close related to stability and other properties of OSA-starch applied in oil-in-water system.