Early results using high-resolution, low-voltage, low-temperature SEM.

J B Pawley; P Walther; S J Shih; M Malecki

doi:10.1111/j.1365-2818.1991.tb03093.x

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Early results using high-resolution, low-voltage, low-temperature SEM.

J B Pawley·P Walther·S J Shih·M Malecki

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Abstract

Recent advances in the design of the scanning electron microscope (SEM) column, such as the coupling of a field-emission gun to a low-aberration immersion lens and the availability of a high-stability cryo-transfer stage, make low-temperature, low-voltage SEM (LTLVSEM) possible at very high resolution. We have used this combination to obtain results with uncoated biological specimens. The trichocyst from a Paramecium was used as a test specimen to observe the shrinkage of this structure as the temperature is raised from 170 K to room temperature following freeze-drying. High-magnification stereo images were obtained of trichocysts that had been prepared by freezing, freeze-substitution and critical-point drying and which were subsequently viewed by LTLVSEM to reduce beam damage and contamination.

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Animals Cryopreservation Freeze Drying Microscopy, Electron, Scanning Paramecium Temperature Journal Article Research Support, U.S. Gov't, P.H.S.

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J B Pawley, P Walther, S J Shih, M Malecki. 1991. Early results using high-resolution, low-voltage, low-temperature SEM.. https://doi.org/10.1111/j.1365-2818.1991.tb03093.x

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