不同厚度细胞薄切片对AFM图像反差的影响  

Effect of The Thickness of Cell Ultrathin Sections on The Topographical Contrast in Atomic Force Microscopy

作　　者：李鑫辉[1] 季彤[2] 孙洁林[1] 张陈平[2] 胡钧[1] 

机构地区：[1]上海交通大学Bio-X生命科学研究中心纳米生物学实验室,上海200030 [2]上海第二医科大学附属第九人民医院,上海200011

出　　处：《生物化学与生物物理进展》2005年第6期562-567,共6页Progress In Biochemistry and Biophysics

基　　金：国家自然科学基金资助项目(30300389);上海交通大学-上海第二医科大学合作研究基金资助~~

摘　　要：利用原子力显微镜(AFM)观察超薄切片的表面,探索表面形貌与切片厚度、朝向等因素的关系以及对图像反差的影响.选择三种不同类型的细胞,培养后按电镜超薄切片法固定、包埋并切片后,将不同厚度的切片区分上下表面转移到云母上,AFM在空气中以接触模式进行观察.结果发现,切片表面细胞相对包埋介质的凸起与凹陷与切片本身的厚度密切相关,并随切片厚度的不同呈现有规律的变化.实验统计结果显示这种现象可能具有普遍性.The effect of the thickness of ultrathin sections on the topographical contrast in the images of atomic force microscopy (AFM) had been studied. Three different cell lines, Tca8113, C6 and ECV-304 were treated with conventional TEM fixation and embedment techniques. Cut by ultramicrotomy and collected with mica pieces, thin sections with different thickness were imaged by AFM on both sides. The images observed from the lower surfaces showed that the cell regions were always concave compared to the epoxy resin regions, and the concavity was increased with the increase of the ultrathin section thickness. Interestingly, the images from upper surfaces showed a peculiar convexness in the cell regions when the thickness is small, and achieved a maximum when the thickness was about 80 mu, and finally became concave when the thickness was larger than 120 nm. Statistic analysis showed that this trend was a general phenomenon. The relevant mechanism has been discussed.

关 键 词：表面形貌 图像反差 超薄切片 原子力显微镜 

分 类 号：Q6-3[生物学—生物物理学]