On the action of ozone on methaemoglobin

The reaction of ozone with methaemoglobin in formic acid, 6 M urea solution, NaOH 0.1 M and in acetic/acetate buffer at pH = 5 has been studied. Electronic absorption data, polarimetric and viscometric measurements clearly show that ozone destroys the haeme prosthetic groups of methaemoglobin and causes a strong denaturation of this protein. Furthermore, also by electronic and by FT-IR spectroscopy it is presented the evidence of the oxidation and denaturation of methaemoglobin caused by O-3 of methaemoglobin. The results of the study, and the associated risks and concerns are briefly discussed in the context of the auto-haemotherapy, a medical practice which involves the treatment with ozone and the re-injection of an aliquot of blood taken from a "patient". (C) 2004 Elsevier Ltd. All rights reserved.