Atomic force microscope study of the isolation and reconstruction of the structure of lipid rafts in erythrocyte
HAO Changchun, WANG Jiajing, ZHU Lingqing, MU Wenning, SUN Runguang
(School of Physics and Information Technology, Shaanxi Normal University, Xi′an 710119, Shaanxi, China)
Abstract:
Using the atomic force microscope(AFM) the human red blood cells were observed. Lipid rafts, which do not dissolve in detergent Triton X—100 components, were extracted by the sucrose density gradient centrifugation at 4 ℃. Langmuir-Blodgett (LB) monolayers of erythrocyte ghost were prepared and observed by the AFM. The experimental results show that the red blood cells took on double-concave disc-shaped with the size of 7.5 μm and lipid rafts showed a small granules structure with the size of 210 nm. The monolayer structure and morphology changed with increasing surface pressure. At the low surface pressure, there was liquid disordered and liquid-ordered coexisting phase structure. When continuing to compress the monolayer, the fluid ordered phase fused to form large flat platform structure with the height of 1.55 nm.
KeyWords:
erythrocyte; lipid rafts; atomic force microscope; Langmuir-Blodgett monolayers
