Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721 302, India.
Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721 302, India.
J Colloid Interface Sci. 2017 Dec 1;507:1-10. doi: 10.1016/j.jcis.2017.07.108. Epub 2017 Jul 29.
Cholesterol (Chol) is a ubiquitous steroidal component of cell membrane and is known to modulate the packing of phospholipids within the bilayer. Thus, Chol has been frequently used in the formulation and study of artificial "model membranes" like vesicles and liposomes. In this work, we have developed a novel anionic surfactant by conjugating two biomolecules, cholesterol and γ-aminobutyric acid via a urethane linkage. We have studied its physicochemical behavior in aqueous buffer. The surfactant has been shown to spontaneously form small unilamellar vesicles above a very low critical concentration in aqueous neutral buffer at room temperature. The vesicle phase was characterized by use of fluorescence probe, transmission electron microscopy and dynamic light scattering (DLS) techniques. The vesicle bilayer was found to be much less polar as well as more viscous compared to the bulk water. The vesicle stability with respect to change of temperature, pH, and ageing time was investigated by fluorescence probe and DLS techniques. The loading efficiency of the vesicles for the hydrophobic drug, curcumin, was determined and its release under physiological condition was studied. The in vitro cellular uptake of curcumin-loaded vesicles to human breast cancer cell line (MDA-MB-231) also was investigated. The MTT assay showed that the surfactant was non-cytotoxic up to a relatively high concentration.
胆固醇（Chol）是细胞膜中普遍存在的甾醇成分，已知其可调节双层中磷脂的排列。因此，Chol 经常被用于人工“模型膜”（如囊泡和脂质体）的配方和研究。在这项工作中，我们通过氨基丁酸的尿烷键将两种生物分子胆固醇和γ-氨基丁酸偶联，开发了一种新型阴离子表面活性剂。我们研究了它在水缓冲液中的物理化学行为。结果表明，该表面活性剂在室温下的中性水缓冲液中，在非常低的临界浓度以上自发形成小单层囊泡。使用荧光探针、透射电子显微镜和动态光散射（DLS）技术对囊泡相进行了表征。与体相水相比，囊泡双层的极性更小，粘性更大。通过荧光探针和 DLS 技术研究了囊泡对温度、pH 值和老化时间变化的稳定性。测定了囊泡对疏水性药物姜黄素的载药量，并研究了其在生理条件下的释放情况。还研究了载有姜黄素的囊泡对人乳腺癌细胞系（MDA-MB-231）的体外细胞摄取情况。MTT 测定表明，该表面活性剂在相对较高的浓度下是非细胞毒性的。
