Stability of DTT in Solution - Storage? (Dec/28/2007 )

hallo,

stupid or not. some say DTT isn´t stable in solution and should be made fresh. why you then can by DTT solution?
this is curious to me.

any experiences with DTT? informations about storage conditions are helpful. the best is to make it fresh, but is there any recommendation to store DTT solution?

thanks

Our lab has some DTT solution, obtained as part of a kit. (I do not know the concentration offhand.) It is kept in a -80 freezer- persons wishing to use DTT make their own working solutions which are kept at -25. Of course, that may be merely custom here, and not correct...but, Invitrogen says Invitrogenthat a 1M stock solution is stable for 1yr at -20 and is good for a couple freeze/thaws. At 4, it is good for <1 week.

This link (Sigma) has a little table showing the half-life at different pH's and a couple of temperatures. Sigma

we prepare a 1M stock in dw and store in the -20C freezer in aliquots (~10 ml). we freeze-thaw as necessary (we normally use at least 2 ml at a time).

We do it as mdfenko described it.

1M stock solution and store in -20C. Have small aliquots. Thaw and use as necessary.