> > Where I can get non-cytotoxic mineral oil for live microscopy? (european
> > sources preferred)
> > Is there any noticeable gas exchange through a mineral oil layer (N2, O2,
> > CO2)?
> > Beat
> >

Good evening,

in the "old times", when synthetic immersionoil was not yet produced,
cedar-wood-oil was used as immersion medium. Its n(d) hardly differs from
that of synthetic immersion oil (1.51525 vs. 1.5150). If I remember
correctly, a TV-advertisement of some cosmetics some years ago proudly
announced a lotion containing cedar-wood-oil (because it would
give you a nicer skin or something like that). I therefore suppose that
a) cedar-wood-oil is not toxic and b) it might be available in the
pharmacy, drug-store or at a cosmetic-producing factory. Since you
probably won't need liters of it but some ccm, only, they perhaps
give it to you free of charge.
I do not know whether there is any noticeable gas-exchange through
cedar-wood-oil. Perhaps a botanist would know.
Unfortunately, I do not know either a factory by heart, but usually
these factories are indicated in the declaration of chemicals used to
produce a cosmetic article.

Best wishes

Johannes

PS: I beg your pardon for my ignorance in the english language, I
freely translated the german "Zedernholzoel" to "cedar-wood-oil",
since I did not find the expression in the dictionary. It might
be the english expression is totally uncommon or wrong, but
Beat perhaps understands anyway.

--
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Paul Johannes Helm

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