I am working on rose bengal stained sediment samples and when I tried to deep freeze the sample at -27C it wouldn't freeze because ethanol, which is used for rose bengal staining, doesn't freeze at -27C (Having freezing point -117C). So I have to remove it. If I directly decant it then some ethanol must be in sediment pore spaces and it causes problem to freeze dryer, and if I use distilled water to dilute it, it removes the salt content from sediment which I don't want to lose.
Ethanol is used for preparing rose bengal solution (2 gram RB + 1 liter ethanol). It is standard protocol for preparing RB solution (Walton, 1952). I really don't have any idea how tetra butyl alcohol (TBA) will perform in yhis manner.
Have you tried to evaporate it? I`m sure that ethanol evaporates propertly at room temperature. You just have to extend the samples to get the maximum surface of evaporation (for instance in opened petri plates) and just wait. Or you also can try to freeze your samples with liquid nitrogen and then keep at -27ºC. We had tried this technique and chemical composition is not affected by liquid nitrogen (See the publication attached).
Good luck!
Article Sediment integrative assessment of the Bay of Cadiz (Spain):...
Ethanol have boiling point 78.37C, so it is not going to evaporate any how at room temperature. Treating with liquid nitrogen will able to freeze ethanol but the freeze dryer I'm using have chamber temperature -45C. So again it is not going to escape samples.
Patrick Druggan is right. Dry the samples in a dry warm place and it should work.
Dear Dharmendra, To stain the forams in order to distinguish live and dead, we use 1 gm RB powder mixed with i litre of water and soak for 2-4 hours.
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