Hi Ray,
I've got a similar concern and contacted SIGMA for advice. I got the following response:
"We test routinely solubility in water (100 mg/ml). A clear to slightly hazy light yellow solution is yielded.
This material is 80-90% pure when prepared, but is very unstable. As much as 10% purity loss per day at 25 °C has been noted. Further it reacts with water.
Solution Stability according to Data for Biochemical Research, 3rd ed., p. 2 (1987):
S-adenosylmethionine is relatively stable in acid solutions and very unstable under alkaline conditions. Stock solutions should be stable when stored at -20° C at pH 2.5-4.0 for one month.The solutions should be warmed up just before use. In addition, solutions after 24 hours at 30°C decomposed 10% at pH 6.6, 32% at pH 7.8 and 70% at pH 8.8."
The above is for SAM I'm still waiting for a response regarding SAH.
Ralf
-----Original Message-----
From: CCP4 bulletin board [mailto:[log in to unmask]] On Behalf Of Ray Changrui Lu
Sent: Wednesday, November 07, 2007 2:48 AM
To: [log in to unmask]
Subject: [ccp4bb] Dissolving s-adenosylhomocysteine
Hi all,
I am in the process of obtaining crystals in complex with
s-adenosylhomocysteine but this compound doesn't dissolve in normal
pH. The final concentration needs to be in mM range so the stock
ideally needs to be at least 50mM. I know SAH is quite soluble in DMSO
but is there anyway to get it in aqueous solution without organic
solvent or strong acid? Thank you very much in advance.
Ray
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