Vezočnik Valerija, Rebolj Katja, Sitar Simona, Ota Katja, Tušek-Žnidarič Magda, Štrus Jasna, Sepčić Kristina, Pahovnik David, Maček Peter, Žagar Ema
University of Ljubljana, Biotechnical faculty, Department of Biology, Večna pot 111, 1000 Ljubljana, Slovenia.
National Institute of Chemistry, Laboratory for Polymer Chemistry and Technology, Hajdrihova 19, 1000 Ljubljana, Slovenia.
J Chromatogr A. 2015 Oct 30;1418:185-191. doi: 10.1016/j.chroma.2015.09.048. Epub 2015 Sep 29.
Asymmetric-flow field-flow fractionation technique coupled to a multi-angle light-scattering detector (AF4-MALS) was used together with dynamic light-scattering (DLS) in batch mode and transmission electron microscopy (TEM) to study the size characteristics of the trioleoylglycerol lipid droplets covered by a monolayer of sphingomyelin and cholesterol, in water phase. These lipid droplet nanoemulsions (LD) were formed by ultrasonication. In parallel, the size characteristics of large unilamellar lipid vesicles (LUV) prepared by extrusion and composed of sphingomyelin and cholesterol were determined. LD and LUV were prepared at two different molar ratios (1/1, 4/1) of sphingomyelin and cholesterol. In AF4-MALS, various cross-flow conditions and mobile phase compositions were tested to optimize the separation of LD or LUV particles. The particle radii, R, as well as the root-mean-square radii, Rrms, of LD and LUV were determined by AF4-MALS, whereas the hydrodynamic radii, Rh, were obtained by DLS. TEM visualization revealed round shape particles of LD and LUV.
采用不对称流场流分馏技术结合多角度光散射检测器（AF4-MALS），并与批式动态光散射（DLS）和透射电子显微镜（TEM）一起，研究水相中由单层鞘磷脂和胆固醇覆盖的三油酰甘油脂质滴的尺寸特征。这些脂质滴纳米乳液（LD）通过超声处理形成。同时，测定了通过挤压制备的、由鞘磷脂和胆固醇组成的大单层脂质囊泡（LUV）的尺寸特征。LD和LUV在鞘磷脂和胆固醇的两种不同摩尔比（1/1、4/1）下制备。在AF4-MALS中，测试了各种错流条件和流动相组成，以优化LD或LUV颗粒的分离。通过AF4-MALS测定LD和LUV的颗粒半径R以及均方根半径Rrms，而通过DLS获得流体动力学半径Rh。TEM观察显示LD和LUV为圆形颗粒。
