Questions? 800-523-5874 | [email protected]
A selection of published work covering a range of applications using plasma chemistry as a preparation technique.
Use of oxygen plasma for differential etching of ordered and disordered regions in organic specimens. Rates of etching reduced from lower molecular weight substances through disordered (amorphous) regions to ordered (crystalline) regions. This allowed identification by replica EM of simultaneous presence of single crystals and spherilites in Polamide 68.
Using replica EM and oxygen ashing it was shown that latex particles of Polyalkylacrylates and Alkylacrylate-Methacrylic Acid Copolymers are aggregates of primary globules, the size of the globules depends upon the polymer.
Oxygen ashing in conjunction with replica EM revealed supra molecular structure with correlation between EM and x-ray diffraction data. Oxygen ashing followed by SEM examination allowed identification of three types of internal flaw in bright fibers. Results showed high concentrations of titanium dioxide in regions containing voids, and highly ordered polymers which had previously been assumed to be defusants.
100um sections of Wistar rat hearts were oxygen plasma ashed and then dissolved and sprayed onto grids. The droplets were then individually analyzed. The method was found to retain volatiles such as sulphur and possibly chlorine. Ashing times when compared to high temperature ashing are considerably reduced.
A review of high temperature ashing and plasma ashing of various materials.
Among many applications the following are highlighted: microelectronic failure analysis; grain boundary composition in mineralogical specimens containing silicates and carbonaceous material; discovery if microvoids and flaws in carbon reinforcing fibers; differential etching of polymers; formation of 3D ash skeletons; studies of modular graphite inclusions in cast iron; mineral staining of brain tissue followed by oxygen ashing.
Plasma incineration used to determine the morphological localization of structure bound mineral and metallic elements within biological cells at TEM levels.
1um sections of fixed and embedded kidney tissue when surface etched by oxygen plasma, allowed etch resistant cell components to be imaged with clarity. Resolution was better that other preparation technique for SEM of internal structures of cells and organelles in bulk specimens of tissue.
A comparison of preparation methods, including plasma ashing, to determine amounts of silicon in cell wall material.
Oxygen ashing of insects allowed the removal of organic material but left the structure intact. This allowed area sectioning for subsequent analysis.
Improved X-ray detectability of elements retained in ash by lowered background counts. Method removes osmium fixative and chlorine to reveal hidden phosphorous peak; pattern fidelity allows micro analytical resolution of 0.1um.
Oxygen plasma used to remove high levels of airborne organic contaminants and to remove filter paper prior to TEM sizing.
As a general technique for SEM, oxygen plasma etching thick sections of a wide variety of different types of embedded tissue yields specimens that show a resolution that is considerably better than that obtainable by most other methods; particularly for viewing internal structure of cells and organelles in bulk structure.
Methods are described whereby asbestos fibers can be counted by phase contrast microscopy and identified on the same membrane filter by optical and SEM techniques. Airborne concentration of different asbestos types in mixed clouds can therefore be estimated.
Improved gas-discharge etching techniques in the Electron Microscope studies of Polyamide structures.
L I Bezruk. Vysokomol. Soyed. A10: No. 6 1434-1437, 1968
Particle and film structures of films of some latexes of acrylic copolymers
V I Yeliseyeva. Vosokomol. Soyed A9: No 11 2478-2481, 1967
Oxygen etching method of making an Electron Microscopy study of Polyethylene Tetraphthalate films
K Z Gumargaliveva. Vosokomol. Soyed. 8: No. 10 1742-1744, 1966
Studies of plasma-etched Polyethylene Terephthalate fibres by SEM and energydispersive X Ray microanalysis
P R Blakey & M O Alfy. Letter to Journal of Textile Institute 1978 No 1
Detection of inorganic materials in biological specimens
Source unknown
Microincineration techniques for electron-microscopic localization of biological minerals
Richard S Thomas. W Region Research Lab, Agricultural Research Service, US Dept, of Ag.
Albany Ca. USA
Use of chemically reactive gas plasma in preparing specimens for SEM and Electron Probe Microanalysis
Richard S Thomas. SE.M/1974 part I proc 7th SEM Symph –April/1974
Low temperature ultra-microincineration of thin section tissue
Wayne Hohman & Harold Shraer. Journal of Cell Biology, Volume 55 1972 pp 328-354
Ultra-microincineration of thin-sectioned tissue
Principles and Techniques of EM-1976
Ultrastructure of cell organelles by Scanning Electron Microscopy of thick sections surface-etched by an Oxygen plasma
W J Humphreys. Journal of Microscopy Vol 116 July 1979
Silica in the mesophyll cell walls of Italian Rye Grass
D Dinsdale Ann. Bot 44 73-77 1979
Ashing moths and various insects
J Bowden (pr comm) Rothampstead Research Station. July 1979
X-ray microanalysis of Epon sections after Oxygen plasma microincineration
Tudor Barnard and R S Thomas Journal of Microscopy Vol 113 Pt 3 Aug 1978. pp269-276
Scanning Electron Microscopy of biological specimens surface-etched by an Oxygen plasma
W J Humphreys. Scanning Electron Microscopy 1979/11. Asbestos counting method using
TEM. Ontario Research Foundation.
In situ identification of Asbestos fibres collected on membrane filters for counting
N P Vaugham and S J Rooker. Ann. Occup. Hyg. Vol 24 No 3 pp281-290 1981.
Plasma Etching and Ashing Principles