question

[MR MIKE]

	I have a general question for the community. It concerns
the vapor diffusion/hanging drop method of growing crystal of 
proteins. When the drop is set up vapor diffuses out of the drop
until equalibrium is reached. What is an accurate method for 
determining the final buffer concentration, while accounting for
any other solutes that are present; like, protein, salts ? 
	Let me state this in another way. Given that the well
solution and the drop have all the same components except that the
drop has protein, how can we estimate the final solutes concentra-
tions in the drop? 

Mr Mike    O O
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