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:[EMAIL PROTECTED] On Behalf Of Ray Changrui Lu Sent: Wednesday, November 07, 2007 2:48 AM To: CCP4BB@JISCMAIL.AC.UK 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
