Abstract
Facilitated transport of oxygen through hemoglobin has been studied by use of a membrane sandwich of hemoglobin, Teflon, and water. Transport is enhanced only when there is a hemoglobin-bound-02 gradient in the pigment. When passing through a fully oxygenated layer, the accelerated transport is carried by an increased diffusion gradient of oxygen pressure through the solvent. The results substantiate experimentally the diffusion gradients proposed by Zilversmit.