Re: [ccp4bb] Vapor diffusion calculator

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CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: Re: Vapor diffusion calculator
From: "Edward A {- dot -} Berry" BerryE {- at -} UPSTATE {- dot -} EDU
Date: 2010-02-02

Next message:
Subject: Re: Vapor diffusion calculator - better measure it !
From: Boaz Shaanan bshaanan {- at -} BGU {- dot -} AC {- dot -} IL
Date: 2010-02-03

Subject: Re: Vapor diffusion calculator
From: Jose Antonio Cuesta Seijo jose {- at -} KEMI {- dot -} KU {- dot -} DK
Date: 2010-02-03

I would like to add that contrary to popular belief, MPD would have to be
treated as a volatile in the example you give below. It vaporizes, although
very slowly, as can be proven by leaving a 1uL drop of it in open air for a
couple of days.

Cheers,

Jose Antonio Cuesta Seijo.

"Jacob Keller" wrote:
> Dear Crystallographers,
>
> Is anybody aware of a calculator for vapor diffusion experiments to plot
> concentrations of various solvent components as a function of time? For a

> simple example, what happens when I mix a protein solution containing
50mM
> NaCl 1:1 with a reservoir containing 50% MPD but no salt? Where is the
vapor
> diffusion equilibrium, and how does the drop composition change as a
> function of time? More complicated would be experiments involving
volatile
> components other than water, as I think, for example, ethanol would
almost
> instantly equilibrate, then the water diffusion would kick in over a
longer
> time scale. Even more complicated would be pH-dependent volatilities such
as
> acetate. I don't think this would be impossible to figure out, but it
would
> be nice if there were a pre-existing tool/server to do such.
>
> Regards,
>
> Jacob Keller
>
>
> *******************************************
> Jacob Pearson Keller
> Northwestern University
> Medical Scientist Training Program
> Dallos Laboratory
> F. Searle 1-240
> 2240 Campus Drive
> Evanston IL 60208
> lab: 847.491.2438
> cel: 773.608.9185
> email: j-keller2@northwestern.edu
> *******************************************
>

--
***************************
Jose Antonio Cuesta-Seijo

Biophysical
Chemistry Group
Department of Chemistry
University of Copenhagen
Tlf:
+45-35320261
Universitetsparken 5
DK-2100 Copenhagen,
Denmark
***************************

CCP4bb navigation

CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: Re: Vapor diffusion calculator
From: "Edward A {- dot -} Berry" BerryE {- at -} UPSTATE {- dot -} EDU
Date: 2010-02-02

Next message:
Subject: Re: Vapor diffusion calculator - better measure it !
From: Boaz Shaanan bshaanan {- at -} BGU {- dot -} AC {- dot -} IL
Date: 2010-02-03