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Simplified Sample Embedding and Polishing Methods for Preparing Hydrophilic, Fragile, or Solvent-Susceptible Materials for Thin Sections for Microscopic Analyses

Part of: Micrographia Collection

Published online by Cambridge University Press:  13 February 2019

Masato Ueshima  and
Hirofumi Sakanakura
Masato Ueshima*
Affiliation:
Center for Material Cycles and Waste Management Research, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan
Hirofumi Sakanakura
Affiliation:
Center for Material Cycles and Waste Management Research, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan
*
*Author for correspondence: Masato Ueshima, E-mail: [email protected]
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Abstract

In the preparation of thin sections for microscopy, embedding and polishing processes in particular can change the composition and morphologies of samples. Soils and ashes are very fragile and solvent-susceptible, and appropriate sample preparation procedures have not been well-established. To improve the existing preparation methods and make them easier and faster, we embedded freeze-dried blocks, polished, and then examined these thin-section samples using polarization microscopy, laser microscopy, and field emission scanning electron microscopy with energy-dispersive X-ray spectrometry, and electron backscattered diffraction (EBSD). Appropriate thin-section samples can be prepared by: (1) rinsing with acetone and then embedding with Spurr resin along with repeated evacuation and ventilation, rather than conventional dehydration/replacement; (2) polishing using silicon carbide paper and diamond slurries, and then wiping with a cloth and a synthetic oil; and (3) slightly rinsing with 100% ethanol to remove the oil. The preparation method minimized contamination and pores, and showed flat surfaces and sometimes EBSD patterns. Freeze-drying has been claimed to cause the development of cracks due to ice crystal formation upon freezing, however, our method not only overcomes such problems for microscopic observation but saves substantial time, taking only 2 days in total to process a specimen, and requiring less than 1 g of resin and ~1 g of sample.

Keywords

laser microscopypolarization microscopySEMsolvent-susceptible specimensthin section preparation
Type
Micrographia
Information
Microscopy and Microanalysis , Volume 25 , Issue 1 , February 2019 , pp. 257 - 265
Copyright
Copyright © Microscopy Society of America 2019 

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References

Bayuseno, AP & Schmahl, WW (2010) Understanding the chemical and mineralogical properties of the inorganic portion of MSWI bottom ash. Waste Manage 30, 1509–1520.Google Scholar
Camuti, KS & McGuire, PT (1999) Preparation of polished thin sections from poorly consolidated regolith and sediment materials. Sediment Geol 128, 171–178.Google Scholar
Electron Microscopy Technology for Medicine and Biology (1997) Easy-to-understand Electron Microscope Technology, 5th ed. Hirano, H and Miyazawa, S (Eds.). Tokyo, Japan: Asakura Shoten Publisher, 309pp. (in Japanese).Google Scholar
Jongerius, A & Heintzberger, G (1975) Methods in soil micromorphology. A technique for the preparation of large thin sections, Netherlands. Soil Surv Inst, Wageningen, Soil Surv Pap 10, 15–19.Google Scholar
Kushida, H (1961) Propylene oxide as a dehydrating agent for embedding with epoxy resins. J Electron Microscopy 10, 203–204.Google Scholar
Kushida, H (1964) Glycol methacrylates as a dehydrating agent for embedding with polyester and epoxy resins. J Electron Microscopy 13, 200–203.Google Scholar
MacPherson, DR & Forbrich, LR (1937) Determination of uncombined lime in Portland cement. Ind Eng Chem 9, 451–453.Google Scholar
Morris, JE (1968) Dehydrated cysts of Artemia salina prepared for electron microscopy by totally anhydrous techniques. J Ultrastruct Res 25, 64–72.Google Scholar
Murphy, CP (1985) Faster methods of liquid-phase acetone replacement of water from soils and sediments prior to resin impregnation. Geoderma 35, 39–45.Google Scholar
Pease, DC (1966) The preservation of unfixed cytological detail by dehydration with inert agent. J Ultrastruct Res 14, 356–378.Google Scholar
Sekimoto, K, Endo, K & Shimizu, K (2008) Holocene deposits and the paleoenvironments in the Tokyo International Airport (Haneda), Northwest part of Tokyo Bay, Central Japan. Ann Rep Inst Nat Sci, Nihon Univ. 43, 337–345 (in Japanese).Google Scholar
Spurr, AR (1969) A low-viscosity epoxy resin embedding medium for electron microscopy. J Ultrastructure Res 26, 31–43.Google Scholar
Stein, O & Stein, Y (1967) Lipid synthesis intracellular transport storage and secretion. 1. Electron microscopic radioautographic study of liver after injection of tritiated palmitate or glycerol in fasted and ethanol-treated rats. J Cell Biol 33, 319–339.Google Scholar