Non-steady-state O-2 diffusion in metmyoglobin solutions studied in a diffusion chamber

In this study, we studied the "passive" diffusion through myoglobin solutio ns by determining the oxygen diffusion coefficient (DO,) and the oxygen per meability (rho O-2) of metmyoglobin (metMb) solutions (3-33 g . 100 mL(-1)) at 25 degrees C. These oxygen diffusion parameters were determined in a di ffusion chamber using a non-steady-state method and were also determined of albumin solutions (4-32 g . 100 mL(-1)) and distilled water for comparison . From these parameters, the oxygen solubility (alpha O-2) could be calcula ted, because alpha O-2 = rho O-2/DO2. Both DO2 and rho O-2, decreased with increasing metMb and albumin concentration. The values of DO2, rho O-2 and alpha O-2 of both metMb solutions and albumin solutions were comparable wit h literature values of methemoglobin (metMb) and serum protein solutions. T he values of the metMb solutions can be used in following studies of facili tated oxygen diffusion through myoglobin solutions. (C) 2000 Academic Press .