What is the function of NADPH in the reaction system? - (Jan/24/2007 )

I used NADPH in my assay.
For the first time, I used fresh-made NADPH and got a good result.
But for the second time, I used NADPH which was made about 1 hour before I add it into the reaction system. Then, the result is bad. There are almost no product.
So I am thinking about 1). the function of NADPH and try to figure out 2). if the time when NADPH is made is the reason of failure.

nadph is a hydrogen (proton) donor for some enzyme reactions. it is very labile, so if it is not stored or handled properly then it will decompose (to nadp and h2). if the solution is strong enough then you may be able to see that it turned orange.

you should hold it on ice for short periods (an hour should be okay). you can store it frozen for longer periods, but, it will still decompose while frozen. we just made it fresh when we needed it.

Got it !
Thank you!