[Jazzified]

In a mixture of glucose-1-phosphate and glucose-1,6-diphosphate, how could you determine the amount of each in the mixture?

I was thinking of using a strong acid to separate the phosphate from the glucose and use Fiske-Subbarow assay to determine the amount of glucose-1-phosphate, but won't this also affect the glucose-1,6-diphosphate?  I am having trouble figuring out how to determine the amount of glucose-1,6-diphosphate in the mixture.

[Rabn]

you could try selective recrystallization. it wouldn't be as destructive. Using the right solvent you can probably selectively recrystallize one of them. It may be a lot easier. Either that or use glucose-6-phosphatase. It will convert all of the glucose-6-phosphate to glucose which you can then reduce. By measuring absorbance with spectrophotometer you can determine the concentration of glucose, I don't believe the diphosphate is a reducing sugar. Those are my thoughts. I like easy, recrystallization or digestion with the enzyme are likely pretty easy. heck you may even be able to salt out one of them.

[sjb]

What else is in the mixture? What analytical techniques do you have access to?

Could you run a ³¹P-NMR ?

S

[Yggdrasil]

What about trying some type of liquid chromatography with an ion exchange resin.