Size and shape determination of fixed chylomicrons and emulsions with fluid or solid surfaces by three-dimensional analysis of shadows.
Size and shape determination of fixed chylomicrons and emulsions with fluid or solid surfaces by three-dimensional analysis of shadows.
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DOI：
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发表时间：
1990
影响因子：
6.5
通讯作者：
Donald L. Gantz;S. B. Clark;Arie Derksen;Donald Small
中科院分区：
文献类型：
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作者：
Donald L. Gantz;S. B. Clark;Arie Derksen;Donald Small
乳胶粒和乳胶粒大小的乳液是悬浮液中的球形颗粒，但它们的形状和表观尺寸可能会因电子显微镜处理而扭曲。为了评估对网格的吸附、扁平化和收缩，乳胶粒和乳胶粒用四氧化二臭氧固定，并与聚苯乙烯珠子一起用铂遮盖。从粒子阴影投射的垂直剖面图显示，乳胶粒和乳胶粒略有缩小，略有截断，呈扁球形，而聚苯乙烯微珠则为球形。通过假设网格表面扁平球体的体积等于原始脂质悬浮液中球体的体积，对颗粒直径进行了修正。由于收缩(缩径)和展平(增径)的补偿作用，测量直径的平均值与校正直径之间的差异小于或等于5%。
Chylomicrons and chylomicron-sized emulsions are spherical particles in suspension but their shape and apparent size may be distorted by electron microscopy processing. To assess adsorption to grids, flattening, and shrinkage, chylomicrons and emulsions were fixed with osmium tetroxide and together with polystyrene beads were shadowed with platinum. Vertical profiles projected from particle shadows indicated that the chylomicrons and emulsions were slightly shrunken, slightly truncated, oblate spheroids while the polystyrene beads were spheres. Particle diameters were corrected by assuming that volumes of oblate spheroids on the grid surface were equal to volumes of spheres in the original lipid suspension. Because of the compensating effects of shrinkage (decreases diameter) and flattening (increases diameter) the differences between the means of measured diameters and corrected diameters were less than or equal to 5%.