Supravital lanthanoid staining for scanning electron microscopy of biological objects

Abstract

Since modern scanning electron microscopes are capable of low-vacuum mode and back-scattered electron detection, no other sample preparation, except for heavy metal staining, is necessary. Rare earth chlorides were used as contrast agents to study ocular tissues, cell cultures, and small invertebrates. It has been shown that supravital lanthanoid staining, if adjusted to meet the requirements of modern technology, significantly increases contrast of back-scattered electron images along with their informative value. Not only the microrelief but also internal structures (5-10 μm beneath the surface) of the samples can be visualized without 'classical' sample preparation. Selective accumulation of lantanoids in cell membranes is likely to be due to their binding to calcium ATPases. The developed method of lanthanoid staining enables the use of scanning electron microscopy for subsurface examination of biological objects

Keywords

scanning electron microscopy / lanthanoids / contrast agent / cell culture

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