[Functional adjuvant for stored red blood cells: ascorbate or oxalate?]

In stored blood cells the p50 and the 2,3-DPG concentration drop rapidly. To compensate the functional resultant weakness, many different additives have been proposed, in particular ascorbate, which is very unstable, and ascorbate-2-phosphate (AsP), which is a little more stable. We have studied the effect of two commercially available AsP whose impurity content was different. It was found that the more the substance was impure the more it was effective. This led as to doubt the effectiveness of ascorbate itself and to try the impurity (oxalate) with which we have obtained the results published with AsP.