Fan Ye, Fang Yun, Ma Lin
The Key Laboratory of Food Colloids and Biotechnology, Ministry of Education; School of Chemical and Material Engineering, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, PR China.
The Key Laboratory of Food Colloids and Biotechnology, Ministry of Education; School of Chemical and Material Engineering, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, PR China.
Colloids Surf B Biointerfaces. 2014 Nov 1;123:8-14. doi: 10.1016/j.colsurfb.2014.08.028. Epub 2014 Aug 29.
Unsaturated fatty acid liposomes (Ufasomes) have attracted interests because of the ready availability of unsaturated fatty acids and the simple assembly strategy. However, the colloidal instability of the ufasomes hinders them from applying in the fields of drug delivery and food additives. In the present work, conjugated linoleic acid (CLA) with triple activities of bioactive, assembling and crosslinking was employed as a new molecular building block to construct ufasome and afterwards crosslinked ufasome. First, CLA ufasome was self-assembled from CLA molecules in response to pH variation, and the suitable CLA concentrations and pH ranges were determined by surface tension measurement and acid-base titration. Subsequently, the self-crosslinked CLA ufasome was prepared by intra-ufasomal crosslinking of conjugated double bonds in the CLA molecules. The morphologies of the self-crosslinked CLA ufasomes were imaged using transmission electron microscopy (TEM), from which the size of 20-50 nm and the bilayer thickness of 2.7±0.5 nm were detected. Most importantly, based on the comparison of the bilayer thicknesses of the different fatty acids, the molecular arrangement in the bilayer membrane of the self-crosslinked CLA ufasome is named "side-by-side" model contrary to the ordinary "tail-to-tail" model. The pH stability of the self-crosslinked CLA ufasome was examined in virtue of dynamic light scattering tests. Finally, in vitro release results of 5-fluorouracil from the self-crosslinked CLA ufasome showed that the process was slow and sustainable.
不饱和脂肪酸脂质体（Ufasomes）因其不饱和脂肪酸易于获取以及组装策略简单而备受关注。然而，Ufasomes的胶体不稳定性阻碍了它们在药物递送和食品添加剂领域的应用。在本研究中，具有生物活性、组装和交联三重活性的共轭亚油酸（CLA）被用作一种新的分子构建块来构建Ufasome以及随后的交联Ufasome。首先，CLA Ufasome由CLA分子响应pH变化自组装而成，通过表面张力测量和酸碱滴定确定了合适的CLA浓度和pH范围。随后，通过CLA分子中共轭双键的脂质体内交联制备了自交联CLA Ufasome。使用透射电子显微镜（TEM）对自交联CLA Ufasomes的形态进行成像，从中检测到尺寸为20 - 50 nm，双层厚度为2.7±0.5 nm。最重要的是，基于不同脂肪酸双层厚度的比较，自交联CLA Ufasome双层膜中的分子排列与普通的“尾对尾”模型相反，被命名为“并排”模型。通过动态光散射测试考察了自交联CLA Ufasome的pH稳定性。最后，自交联CLA Ufasome对5 -氟尿嘧啶的体外释放结果表明该过程缓慢且持续。
