Interference in colorimetric reactions for measuring hydrogen peroxide.

We describe evidence that serum samples from patients with chronic renal failure possess a constituent that interferes with the measurement of uric acid when using a method employing uricase with peroxidase-assisted detection of the hydrogen peroxide generated. The interference is also reflected in reduced recovery of both hydrogen and sarcosine when added to serum from patients with chronic renal failure. The interferent may be protein in nature or protein bound, as the poor recovery of hydrogen peroxide is seen in patients' serum before and after haemodialysis.