1/21/99
I am attempting to examine embrylogical samples of a marine bivalve
using SEM. But any containers I have used during the processing
proceedure have proved indequate. I need containers which will hold
samples down to a size of 30um. I have used filters placed in processing
capsules but they are very awkward, and the sample has more often than
not been lost during the proceedure.
Any ideas would be greatly appreciated.
Jean Raleigh,
Marine Zoology Dept.,
Natioal University Galway
Ireland
Jean.Raleigh@nuigalway.ie
I routinely refer to two articles regarding this type of SEM prep.
Preparation of Microbiological Specimens for Scanning Electron Microscopy,
L.P. Watson, A.E. Mckee, and B.R. Merrell. Scanning Electron
Microscopy/1980/II, pages 45-56.
Specimen Preparation Techniques for Aquatic Organisms, T.K. Maugel, D.B.
Bonar, W.J. Creegan and E.B. Small. Scanning Electron Microscopy/1980/II,
pages 57-77.
Hope this helps,
Louie
Louie Kerr
lkerr@mbl.edu
put nets made of metal or nylon, meshs 20 µm, in our holder for CPD.
For very small things, e.g. bacteria, zoospores, we introduce the
samples with syringe and needle into LUMitainers. Lumitainers are
little balls D=2,5-3,5 mm made of a kind of cellulose. They are
useful for both SEM and TEM. In Germany you can buy them by Plano W.
Planet GmbH, Marburgerstr. 90, 35043 Marburg, Fax 06425-51173. They
are not cheap! I do not know where to get it abroad?
Good luck!
Anne Heller
_____________________
Dr. Anne Heller
Institut fuer Botanik (210)
Universitaet Hohenheim
Garbenstr.30
D-70593 Stuttgart
Tel.0049-711-459-2180
Fax 0049-711-459-3355
heller@Uni-Hohenheim.DE
Try folding small (10 x 10 mm) envelopes from lens tissue. Close
with a small staple. These envelopes are permeable enough for
processing. They work very well for pollen and erythrocyte
samples.
Some types of lens tissue have rather large pores - I have seen
holes up to 30 microns in some makes of tissue - check yours
before using.
Jan Coetzee
Microscopy & Micro-analysis UP
janc@ccnet.up.ac.za
This is easy and cheap to make:
_ /_____\ _
| | | |
| | | | <-- BEEM capsule
|_|_____ |_|
\ /
^ ^
|____|__ plankton netting
(I hope the ascii "art" survives the 'net...)
Cut out the center of the lid of a BEEM capsule, leaving a ring that still
snaps onto the body of the capsule as usual. Close the lid, trapping a taut
bit of plankton netting under it.
Cut off the lid from a second BEEM capsule and cut out its center as above.
Cut of the pyramidal end from the first BEEM capsule, and snap the cut-off
end over the new end of this capsule, again trapping a bit of plankton
netting.
The netting comes in various sizes, so you can get one small enough for
your needs, but use the largest size mesh you can to ease fluid flow.
Problem: when changing solutions before drying, the mesh will trap air. The
best way to deal with this is to leave the 2nd end of the capsule open, and
place the capsule mesh-end down in a 4mL Wheaton vial or similar. Change
solutions by sucking out the old solution from the vial outside the
capsule, and pipetting in the new solution into the open end of the
capsule. Don't fill the capsule/vial completely, or the specimens might
float out into the vial.
When ready to dry, snap on the 2nd lid with netting, suck some of the final
fluid change into the capsule so there is no air bubble, then CPD.
I've also dried marine gastropod larvae from HMDS, no CPD with good
results. These capsules work well for that also, and don't need the 2nd lid
then.
Phil
oshel@terracom.net
Philip Oshel