> From: kraushaa at hotmail.com (Udo Kraushaar)
> Message-Id: <kraushaa.21.005566F0 at hotmail.com>
> I'd like to perform perforated patches with Gramicidin. Actually I
> tried out a receipe where G. is solved in DMSO (5 mg/1ml). when I
> add this stock to my pipette solution the G. falls out. Using
My ancient Merck [7th Ed!] lists two forms, a `D' and `S' form. G. D is
soluble in lower alcohols, acetic acid and pyridine, moderately soluble in
_dry_ acetone and dioxane and practically insoluble in ether and
hydrocarbons. It is stated to form colloidal suspensions in water. The `S'
[also given as `C'] form is freely soluble in alcohol, slightly soluble in
acetone and insoluble in water, acids and alkalis.
It seems that whenever your stock is added to your polar solution, the
DMSO is going to run off and dance with the large crowd of promiscuous
ions, leaving the G. unloved and unwelcome. Have you searched the
literature to see what studies have been made of its somatic transport? -
You may need to form a colloid with lipids. The best you will get
otherwise is 0.6 mg/100 ml using Gramicidin D (Dubos).
Source: Merck Index [7th Ed.](1960) pg:497.
Terry "Nothing like a biochemist, but I'll play anything on the Net"
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