By Paulo Camuri on Friday, March 19, 2004 - 03:18 am:
Hi felows,
IŽd like to know how to convert the polarity of Methanol 90% : water 10% for acetonitrile and water, for exemple.
How much is it gonna be?
Is there some table?
Thaks,
By Bernd Mischke on Friday, March 19, 2004 - 03:58 am:
Hi Paulo,
try it with 70% ACN. But don't forget, that this solvent has other types of properties so like less proton donor and more proton acceptor function. Depending on Your samples You can get selectivity changes.
By HW Mueller on Friday, March 19, 2004 - 07:14 am:
You want to have the same elution power as with 90+10 MeOH+H2O? A nomograph in Snyder, Glajch, Kirkland, Practical HPLC Development, Wiley, 1988, p. 32 gives ~ 86+14 for ACN+H2O.
By Paulo Camuri on Monday, March 22, 2004 - 10:49 am:
Hi Mueller,
is this a monography (in a journal) or a book?
Anyway, I apreciate your help.
Paulo Camuri
By Tom Mizukami on Monday, March 22, 2004 - 12:00 pm:
See figure 3.
http://www.mac-mod.com/pdf/PolarEmbed3.pdf
By Uwe Neue on Monday, March 22, 2004 - 03:26 pm:
Schoenmakers rule:
f (MeCN) = 0.32 f (MeOH) ^2 + 0.57 F (MeOH)
Haddad rule:
f(MeCN) = 0.9 * f(MeOH)^2 -0.21 f(MeOH) +0.126
f is the volume fraction.
The truth is most of the time in between