微胶囊横断面的冷冻扫描电镜制备方法研究
莫家媚,张少鸿*,苏秋成
(中国科学院广州能源研究所分析测试中心,广东广州510640)
摘 要 不同结构的微胶囊具有不同功能与用途,冷冻扫描电镜(Cryo-SEM)不仅可以直接观察含水样品的表面形貌,还可以简单快速地对样品进行冷冻断裂,表征内部结构。本文以蛋白微胶囊为实验材料,应用Cryo-SEM探索微胶囊内部显微结构的分析表征方法。实验结果表明:采用铆钉法可以简单快速地制备出蛋白微胶囊的横断面,经过-90℃升华15 min处理后,可以清晰地观察到蛋白微胶囊内部实心、中空、疏松和多孔结构,实现了制备、观察一体化。该方法不需要任何化学试剂,操作简单,快速有效,不仅截面平整,轮廓清晰,孔洞结构不变形,而且成像立体感强,适用范围广,可用于内部实心、中空、疏松和多孔等不同类型蛋白微胶囊内部显微结构的观察。
关键词 蛋白微胶囊;冷冻扫描电镜;冷冻断裂
中图分类号:R944.5;R94;R98 文献标识码:Adoi:10.3969/j.issn.1000-6281.2022.03.013
Study on preparation of microcapsule cross section by Cryo-scanning electron microscopy
MO Jia-mei,ZHANG Shao-hong*,SU Qiu-cheng
(Analysis and Testing Center, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou Guangdong 510640, China)
Abstract The different structures of microcapsules have different functions and uses. Cryo-scanning electron microscopy (Cryo-SEM) could not only directly observe the surface morphological of without drying samples, but also obtain cross section of samples by freeze-fracture to analyze the internal structure. In this paper, protein microcapsules were used as experimental materials, the rivets method was used to obtain the cross section of the sample, and the effects of sublimation on the cross-section morphology of Cryo-SEM were discussed. The results showed that the rivets method could easily and quickly obtain the cross section of protein microcapsules. The ice around the sample by etching to make the sample show up. After sublimation at -90 ℃for 15 min, the filling, hollow, loose and porous structure of protein microcapsules could be clearly observed, which realizing the integration of preparation and observation. This method without any chemical reagents, operation simple and speed, three-dimensional imaging sense, and can be used to observe the internal microstructure of different types of protein microcapsules which flat section, clear contour, no deformation of the structure.
Keywords protein microcapsules; Cryo-scanning electron microscopy (Cryo-SEM); freeze-fracture
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