分子动力学模拟研究不同乳化剂稳定的纳米乳液油/水界面行为  

Molecular Dynamics Simulation to Study the Oil/Water Interfacial Behavior of Nanoemulsions Stabilized by Different Emulsifiers

作　　者：杨怡霜 熊厚盛 解新安[1] 黎攀 杜冰[1] 李璐[1] YANG Yishuang;XIONG Housheng;XIE Xin’an;LI Pan;DU Bing;LI Lu(College of Food Science,South China Agricultural University,Guangzhou 510642,China)

机构地区：[1]华南农业大学食品学院,广东广州510642

出　　处：《食品科学》2024年第23期35-45,共11页Food Science

基　　金：广东省自然科学基金面上项目(2023A1515011359)。

摘　　要：为揭示辛烯基琥珀酸酯化(octenyl succinic anhydride,OSA)改性淀粉、吐温80/司盘80(Tween-80/Span-80,T/S80)和卵磷脂3种乳化剂构建的纳米乳液在油/水界面行为上的差异,采用流变仪和接触角测量仪分析三者构建的乳液体系的剪切流变特性和界面吸附动力学,并运用分子动力学模拟对其微观油/水界面行为机制进行深入探究。结果发现:OSA分子在油/水处界面张力最低,而T/S80在油/水界面层的扩散速率最大,这与以碳链为骨架的T/S80易分散在水中有关。OSA乳液与水产生的氢键数最多,达到1300左右,展现出更强的疏水作用,同时也解释了其液滴形态为何最接近球形。以碳链为基本骨架的OSA改性淀粉分子和T/S80分子倾向于与水分子形成范德华力;而以甘油为骨架的卵磷脂的两条碳链有一定的相互排斥作用,表现出更为多样的弱相互作用。To reveal the difference in the oil/water interfacial behavior of nanoemulsions prepared separately with three emulsifiers,octenyl succinic anhydride(OSA)-modified starch,Tween-80/Span-80(T/S80),and lecithin,this study employed a rheometer and a contact angle meter to analyze the shear rheological properties and interfacial adsorption dynamics of the emulsion systems.Furthermore,molecular dynamics simulation was utilized to delve into the underlying mechanisms of their microscopic oil/water interfacial behavior.The findings revealed that OSA exhibited the lowest interfacial tension at the oil/water interface,while T/S80 demonstrated the highest diffusion rate within the oil/water interfacial layer.This was primarily attributed to the carbon chain-based structure of T/S80,which facilitated its dispersion in water.The number of hydrogen bonds formed between the OSA-modified starch-stabilized emulsion and water molecules was the largest,approximately 1300,indicating stronger hydrophobic effect and explaining why the emulsion droplets were the closest to a sphere in shape.OSA-modified starch and T/S80 molecules tended to form van der Waals force with water molecules.In contrast,the two carbon chains of lecithin,with glycerol as its backbone,showed a more diverse range of weak interactions because of their mutual repulsion.

关 键 词：分子动力学模拟 辛烯基琥珀酸酯化改性淀粉 吐温80/司盘80 卵磷脂 界面行为 纳米乳液 

分 类 号：TS201.7[轻工技术与工程—食品科学]