Facilitated Diffusion of CO and Oxygen in the Presence of Hemoglobin or Myoglobin

Abstract

Kreuzer and Hoofd (1970, 1972) presented an approximate analytical solution of the basic equations of facilitated diffusion including chemical reactions for the systems Hb + O₂ and Mb + O₂, and investigated the effects of various factors of possible importance including the values of the diffusion coefficients, the chemical reaction rates, the actual diffusion path length, a possible back pressure of oxygen on the low-pressure side, and nonequilibrium versus equilibrium approach. They assumed the presence of three regions in the layer: a middle core very near equilibrium and two marginal regions not at equilibrium (similar treatment by Smith et al., 1973). In their recent review Schultz et al. (1974) showed that this analysis leads to solutions which are valid over a wide range of Damköhler numbers (which, in diffusion-reaction problems, is the ratio of certain characteristic times for diffusion to certain characteristic or relaxation times for chemical reaction).