4/24/97
I am still having problems with my cpd efforts giving me 'raisins'
especially on young plant tissue. Has anyone used HMDS? How do the
results compare to CPD, or Freon (I know I can't use freon, but it used to
be the standard)?
Are there any tricks I should know before embarking on a HMDS experiment?
Thanks for letting me pick your brains.
Paula Sicurello
UC Berkeley
Electron Microscope Lab
psic@uclink4.berkeley.edu
sure that ou have gotten ridof all the water and solvent before drying
Sniff the chamber when you open and see if you still smell solvent. If yes
you need longer or more changes during CPD
G.W. Erdos, Ph.D. Phone: 352-392-1295
Scientific Director,
ICBR Electron Microscopy Core Lab
218 Carr Hall Fax: 352-846-0251
University of Florida E-mail: gwe@biotech.ufl.edu
Gainesville, FL 32611
Dr. Beverley Giamarra has done a lot of work with HMDS.
Below is a bibliography of HMDS work I am familiar with:
If you hear of any others I'd appreciate your forwading them to me.
HMDS
Adams JL, Battjes DA, and Buthala DA. (1987). Biological Specimen
Preparation for SEM by a Method Other Than Critical Point Drying. Proc.
EMSA. 45, 956-957.
Giammara B, Baker R, Burkes E, Malangoni M, Evers B, and Hanker J.
(1987a). Hexamethyldisilazane for Rapid Scanning Electron Microscopic
Examination of Implant Specimens. (abs) J. Dent. Res. 66, 187.
Giammara B, DeVries W, Baker R, Dobbins J, and Hanker J. (1987b).
Hexamethyldisilazane Drying for Rapid Detection of Bacteria in Implant
Specimens. Proc. EMSA. 45, 878-879.
Giammara B and Hanker J. (1988a). Ruthenium Red-Osmium Bridging with TCH:
New Technique to Stain Biological Specimens for Light and TEM and to Coat
for SEM. Proc. EMSA. 46, 20-21.
Giammara BL and Hanker JS. (1988b). New Ruthenium Red Bridging Technique
with Thiocarbohydrazide to Stain Polyanionic Biomacromolecules for Light
and Electron Microscopy and to Coat Biological Specimens for Scanning
Electron Microscopy. Proc. 9th Eur. Cong. Elec. Mic.
Giammara B, Washburn M, Malangoni M, Evers B, Baker R, Burkes EJ, and
Hanker J. (1987c). Rapid Scanning Electron Microscopic Examination of
Implant Specimens with Hexamethyldisilazane Drying. Soc. for Biomaterials
Trans. X, 103.
Lamoreaux W. (1988). Prevention of Outgassing When Coating Tissues Dried
with Hexamethyldisilazane (HMDS). EMSA Bull. 18, 91.
Nation JL. (1983). A New Method Using Hexamethyldisilazane for
Preparation of Soft Insect Tissue for Scanning Electron Microscopy. Stain
Technol. 58, 347-351.
HMDS SAFETY NOTES
HMDS is flammable, use in a flammables rated exhaust hood. Avoid breathing
vapors. It is toxic by inhalation, toxic sin contact with skin, or if
swallowed. I have observed that HMDS seems to produce an ammonia compound
when mixed with ethanol.
Other than the above common sense precautions, it is very easy to use as a
final solvent treatment after fixation, post-fixation and dehydration. I
have not used it myself with plant material.
good luck
Edward J. Basgall, PhD
The Pennsylvania State University
Surface Chemistry Group ejb11@psu.edu
Materials Research Institute Building Ph: 814-865-0493
University Park, PA 16802-7003 FAX: 814-863-0618