ADP solution - Checking the ATP contamination (Jun/17/2009 )

hi everybody,
I have to solve this point, please help me!

In my experiment I have to prepare some reagents that have not been contaminated by ATP. I need the pure ADP solution, therefore, I used Lr/L reagent in the ATP assay (Promega) to check the ATP contamination in both of water and ADP solution.
I used the Luminometer to measure the presence of ATP in ADP solution. The control is only water. Unfortunately, the value got from the sample containing ADP solution is very high comparing to the control. I don’t know why the ADP solution containing ATP? because the water used as its solvent was not contaminated by ATP. And ADP solution making condition is not ATP-contaminated.
Could any one help me explain why in the ADP solution (using water as a solvent), the ATP component is appeared?

Thank a lot!
Chimse

chimse,

I don't know what the source would be, but I do know that you can remove ATP contamination with Hexokinase. Motojima & Yoshida (2003) did something very similar to what I believe you need to do...

http://www.ncbi.nlm.nih.gov/pubmed/12736270

Cheers,
-Carlton