为了获得靶向人体消化道下端的功能因子微囊薄膜载体材料，本研究通过改变辛烯基琥珀酸淀粉酯（OSAS）的取代度、分子量及海藻酸钠复合比例调控OSAS/海藻酸钠复合薄膜的载体性能，利用傅里叶变换红外光谱（FTIR）、X射线衍射（XRD）、小角X射线散射（SAXS）系统探讨了海藻酸钠复合比例、OSAS取代度和分子量对复合薄膜结构和载体性能的影响规律。结果发现，海藻酸钠通过氢键与OSAS分子发生相互作用，海藻酸钠复合比例和OSAS取代度的提高及OSAS分子量的适度降低可促进复合薄膜有序微区的形成，诱导复合薄膜在胃液中的溶解率降低12.10%~18.90%；此外，提高海藻酸钠复合比例和OSAS取代度可诱导复合膜材的快消化成分降低3.6%~18.5%、抗消化成分提高11.1%~29.9%。研究结果为OSAS/海藻酸钠复合薄膜作为小肠末端或结肠靶向功能因子递送系统的载体材料奠定了基础。

In order to obtain film carrier materials for microencapsulating the functional factors targeting the lower end of the human digestive tract, this study regulated the carrier performance of octenyl succinate starch (OSAS)-sodium alginate composite film by changing the substitution degree of OSAS, molecular weight of OSAS, and sodium alginate-to-OSAS ratio of the composite. The effects of sodium alginate-to-OSAS ratio of the composite, and the substitution degree and molecular weight of OSAS on the film structure and carrier properties of OSAS-alginate composite films were studied by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and small-angle X-ray scattering (SAXS). Results indicated that sodium alginate interacted with OSAS molecules via hydrogen bonding. The increase in the proportion of sodium alginate and the degree of OSAS substitution along with a moderate decrease in the molecular weight of OSAS could promote the formation of ordered microdomains of the composite film and induce a decrease of the dissolution rate for the composite film in gastric juice by 12.10%~18.90%. In addition, increasing the proportion of sodium alginate and OSAS substitution could induce the reduction of the fast-digested components of the composite film by 3.6%~18.5% and the increase of the anti-digestion components by 11.1%~29.9%. The results laid the foundation for the OSAS-sodium alginate composite film as a carrier material of the delivery systems for functional factors targeting the end of the small intestine end or the colon.

国家自然科学基金项目（31771930）；广东省“扬帆计划”引进创新创业团队专项资助（2014YT02S029）