Influence of ozone on the rheological and electrical properties of stored human blood

Blood stored in a blood bank undergoes a series of chemical changes and storage lesions. The purpose of this study was to assess the effect of ozone on the rheological and electrical properties of stored human blood. Venous blood samples, obtained from three healthy humans, were treated with different concentrations of ozone (30, 50, 70 and 80 µg/mL) for three weeks in vitro. Ozone was generated from portable medical-grade oxygen using elec-trical corona arc discharge. The ultraviolet-visible absorption of hemoglobin in the wavelength of 300–700 nm showed that ozone in this range did not interact with iron ions and it was not toxic below the concentration of 80 μg/mL. The changes of blood viscosity were also measured. The electrical conductivity and permittivity, in the frequency range from 5 to 50 MHz, were measured in the control and treated samples subjected to different con-centrations of ozone at different stored periods. The results showed that the conductivity and permittivity meas-urements may serve as a useful indicator in the quality assessment of blood samples stored in the blood bank.