Analysis of Facilitated Oxygen Transport in a Liquid Membrane of Hemoglobin

A liquid membrane containing bovine hemoglobin (Hb) as an oxygen carrier was prepared, and oxygen permeation through the membrane was measured by the electrochemical reduction of the permeated oxygen. The oxygen permeation was facilitated, as analyzed by a dual-mode model, to give permeation parameters of the membranes such as the diffusion coefficient (D_Hb) of the mobile carrier Hb and the solution-diffusion coefficient of oxygen (D_o2). The facilitated permeation was the product of the Hb concentration ([Hb]₀) and D_Hb in the membrane solution. D_Hb decreased with [Hb]₀ or the solution viscosity; the maximum of the oxygen permeability (6.2 × 10^-8 cm³(STP)cm cm^-2s^-1 cmHg^-1 at the feed stream oxygen pressure of 0.54 cmHg) was observed at [Hb]₀ = 12.8 g dl^-1, where the facilitation factor and the oxygen/nitrogen permselectivity were ca. 10 and 18, respectively.