6/16/96

HI MICRO-FANS, ATTEMPTS TO SECURE WAX SECTIONS FOR SEM-EDXA HAVE BEEN SOMEWHAT UNSUCCESFUL. AFTER CONDUCTIVE COATING SECTIONS CURL AND SOME- TIMES PARTLY DETACH. TECH INFO WOULD BE GREATLY APPRECIATED.

MATT KLEABONAS
KLEABONAS.MATTHEW_P+@ALBANY.VA.GOV

Matt: I had to do the same sort of thing on paraffin sections and I had our histologist cut the sections and place the sections on carbon planchets. I then deparaffinized the sections while they were still on the planchet. I looked at them uncoated in the SEM and did EDAX. I usd different tissues such as kidney, heart, brain, etc. I was looking for silicon particles coming from the tubing during cardio-pulmonary bypass operations. The sections seemed to adhere to the carbon planchets. Don't know if this will help or not with your applications, but you can give it a try.

rutledge phil
prutle1@gl.umbc.edu

Try poly-l-lysine or chromating the stubs--chrome albumin or chrome gelatin, as is done for slides.

Philip Oshel
oshel@ux1.cso.uiuc.edu

Matt - I have attached histological sections to graphite specimen holders routinely without problems. I cut the sections in the usual manner, floating them on a warm water bath. I coat the graphite holder (JEOL TEMSCAN type) with the regular histological albumin fixative (Poly Scientific Albumin Fixative "Mayer", Cat. #S110; 70 Cleveland Ave. Bay Shore, NY 11706). I pick up the floating paraffin section just like I was mounting it onto a glass slide, and let it dry. You might try warming it SLIGHTLY to improve adhesion. Then I soak it in xylene to remove the paraffin. Then I let the xylene evaporate over night. Sometimes I put the mounted specimens into the vacuum evaporator and pump it down over night to remove all traces of xylene before carbon coating them. Secondary electron imaging will give you an image that readily correlates with photographs of adjacent serial histo sections made with the light microscope. And backscatter imaging will show up exogenous mineral particles for EDS.

Joiner Cartwright, Jr., Ph.D.
Internet: joiner@bcm.tmc.edu

Dear Matt,
Recently I had to do a similar thing with lung tissue suspected of having asbestos particles. We couldn't risk having the particles fall out (in a water bath or deparaffinizing). I used a cambridge-type carbon stub, placed the section directly onto the stub and heated it in my paraffin oven. It adhered nicely, and as the paraffin melted the section was exposed. I then carbon-coated it. Hope this helps.

Kathy Walters
email: kwalters@emiris.iaf.uiowa.edu

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