脂质体结构特性的原子力显微镜研究

Structures and properties of liposome by atomic force microscope

用原子力显微镜 (AFM)研究了 1,2 二油酸甘油 3 磷酸 1 甘油 (DOPG)脂质体胞囊的形态和脂双层膜结构 .报道了AFM探针与吸附在氧化硅膜上脂质体的相互作用结果 .实验结果表明 ,在液晶态的DOPG中 ,AFM图像是一些球形或椭球形颗粒 .这些球形或椭球形颗粒与液晶态的DOPG脂质体的结构特性有关 .当AFM的探针与脂质体表面相互作用力超过某临界值时 ,脂质体胞囊破裂 ,变成脂双层结构 .从图上可以看到 ,第二层的DOPG膜吸附在第一层上 ,膜的厚度约为 5nm .

Bilayer structure and morphology of 1,2-Dioleoy-sy-Glycero-3-[phospho-rac-1-Glycerol] (DOPG) liposomes has been investigated by atomic force microscope(AFM). Results of studies on the interaction between the tip of an atomic force microscope and the liposomes adheres on the silicon wafers are also reported. Experiments demonstrated that there are some spherical and elliptic relief in the AFM image, which they can be regarded as the vesicles of DOPG liposome in the liquid crystalline state. When the operating force of interaction between AFM tip and the surface of liposome are beyond critical values, the liposomes rupture into bilayers. Experiments show that a single DOPG second layer adhered on the DOPG first layer. The membranous thickness in the topographic image is about 5 0 nm.