Question
Posted on: March 6 2013How to prepare oxygen water now that phenacetine is no longer available?
Answer
Phosphoric acid is a possibility. Another mentioned is Napyrophosphate, which is not mentioned in the product list of the distributors of pharmaceutical raw materials in Belgium. But we can assume that napyrosphate, dissolved in water, hydrolyzes to 2 molecules of disodium hydrogen phosphate. So there is the possibility to use this salt that is available. The concentration, which is used for napyrophosphate is 0.05%. This concentration corresponds to this of phosphoric acid. For disodium hydrogen phosphate, this is 0.05% x 284/266 = 0.054% I suspect there will be a difference in acidity between the 2 possibilities. I would prefer that solution, which is the least acidic.