Figure 3.

The permeability, P_lip, of the lipid layer as a function of the bilayer/water partition coefficient, K_i(bilayer, aq), for different structures. Solid line, the CLP model of the alveolar surfactant layer as depicted in figure 2a; dashed line, stack of bilayers separated by aqueous films of the same size as the CLP model as depicted in figure 2b; dotted and dash-dotted line, homogeneous aqueous and hydrocarbon phase, respectively. Partition coefficients for O₂ and CO₂ (estimated from octanol/water partition coefficient; Battino et al. 1968) are indicated by arrows.