Measurement of endogenous alloxan in human blood

For determination of endogenous alloxan content in blood of healthy donors it was stabilized by rapid lowering pH in a sample to 2.0. Alloxan was then allowed to form a colored product in a reaction with [ital]o-phenylenediamine and its content was measured by spectrophotometry using an internal calibration curve. Analysis of 75 blood samples of healthy volunteers has shown that in most donors alloxan concentrations vary from 41 to 265 μmol/l. However, in a small group of healthy people alloxan levels greatly exceeded the above-mentioned limit.