Theresa,
In addition to the comments provided, you do need to consider the vapor
diffusion experiment process as a whole. The primary reasons why we put the
precipitant mixture in the reservoir, aside from being lazy, is (1) it provides
a straight forward and partially accurate starting point
Dear all
In *initial screening* using vapor diffusion crystallization, does it matter
whether the reservoir buffer is also the precipitant in the drop or just a high
salt solution like 5 M NaCl?
Thank you.
Theresa
You should and can try, but I guess 5 M NaCl will dry your drop quite fast,
unless in your drop NaCl concentration is ~2,5 M :-) That is why first mixture
of well and protein solution is 1:1 v/v.
Other variations such as 1:9, 9:1 etc sometimes help.
Dr Felix Frolow
Professor of Structural
:17 PM
To: CCP4BB@JISCMAIL.AC.UK
Subject: Re: [ccp4bb] Reservoir buffer
You should and can try, but I guess 5 M NaCl will dry your drop quite fast,
unless in your drop NaCl concentration is ~2,5 M :-) That is why first mixture
of well and protein solution is 1:1 v/v.
Other variations such as 1:9, 9
Dear Theresa,
an interesting question, I think the answer is yes it does, very
much. Using Raoult's law we can calculate the equilibrium vapour
pressure above a 5M NaCl solution, it is a relative humidity of 82.6%.
This is much lower than say a solution of 20% PEG 4000, here we can
again
