Hi conch,
Yes, that's righ Paul. I am agree. I have been the same results.
David.
David Maceira F.
Malacologist.
Centro Oriental de Ecosistemas y Biodiversidad. BIOECO.
Museo de Historia Natural "Tomas Romay".
Enramadas 601 esq. Barnada.
90100. Santiago de Cuba.
e-mail : [log in to unmask]
On Fri, 13 Mar 1998, Paul Monfils wrote:
> Hi Marlo,
>
> Either isopropyl alcohol (= isopropanol) or ethyl alcohol (= ethanol)
> can be used as a dehydrant/dessicant with equal success. I use
> ethanol (about 3-4 gallons a week) here in the tissue laboratory
> where I work, for dehydration of tissue samples prior to histological
> studies. Ethanol is the most commonly used dehydrant in this kind of
> work; however some laboratories do prefer isopropanol, and I myself
> have substituted isopropanol on occasion, when ethanol was out of
> stock. Ethanol has a greater affinity for water, and a somewhat
> smaller molecular size, so theoretically it may penetrate and
> dehydrate tissues somewhat faster than isopropanol, but the
> differences are not major. Otherwise, they should work equally well.
> Either can be purchased in a pharmacy as "rubbing alcohol". Read the
> label - some rubbing alcohols are made from ethanol, some from
> isopropanol. For dessicating samples, the concentration of alcohol
> is more important than the specific alcohol used. You mentioned
> using 70-75% alcohols. These do a pretty good job, but of course
> they will not completely dessicate a sample, since they contain
> 25-30% water (which subsequently evaporates when you dry the shells).
> However, dessication would be more thorough, and drying faster, if
> you used a stronger concentration of alcohol. 90% isopropyl alcohol
> is often available in the pharmacy.
> The hydrogen peroxide recommended by Jim and Bobbi should do a good
> job of deodorizing, but not in the same way as alcohols. Peroxide
> works more like bleach. They are both in a category of chemicals
> known as strong oxidants. They can destroy odoriferous compounds,
> and even dissolve soft tissues of a mollusk. But they do not
> dessicate, since they are aqueous solutions (almost 100% water).
> Alcohols on the other hand, dessicate tissues, but will not dissolve
> them no matter how strong the solution or how long the exposure.
>
> Paul M.
>
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