Any problems with going directly from ethanol into carbon dioxide or is amyl acetate useful in between? My specimens look OK using just ethanol.

Also: I am experiencing a run of failing (most often between 400 and 800 psi) front window Dowty seals on my drying unit even if I do only 'dry' (carbon dioxide only) test runs. Is anyone else having this problem? This device has been operating for 17 years with few leaks. All sealing surfaces are smooth and clean.

Jim Romanow
bsgphy3@uconnvm.uconn.edu

Dear Jeff; I highly suggest the following general article on CPD:

"Critical Point Drying Techniques", E.R. Lewis and M.K. Nemanic, Scanning Electron Microscopy/1973. You can probably get this article through any search, and it's quite good. In fact, this article points out that amyl acetate is reported to dissolve some of the plastic substrates (polystyrene) used to culture cells.

I found the direct transition from EtOH to CO2 very useful when I first started using CPD on corneal tissues. This work is published in the EMSA proceedings for 1992, "Evaluation of the Biocompatibility of Polymer Surface Modifications with the Corneal Endothelium", R. Citron, et al. If you do not have a copy of those proceedings and would like a copy of the article, let me know.

Bob Citron
Bob_Citron@cc.chiron.com