[Measurement of the endogenous alloxane in human blood]

To determine the endogenous alloxane content in blood of healthy donors we stabilized it by rapid lowering of pH in the sample to 2.0. Alloxane was then allowed to form a colored product in a reaction with o-phenylenediamine and its content was measured by spectrophotometry using an internal calibration curve. The experiment showed that the concentration of alloxane in blood of most of the healthy donors varied from 41 to 265 micromol/l. However, a small group of healthy people was had their blood alloxane level greatly exceeding the above-mentioned values.