title: O2 transfer kinetics in a whole blood unicellular thin layer.
abstract: A planar monocellular layer of whole blood (WB) sandwiched between two Gore-Tex membranes is used to study O2 uptake and release kinetics at 37 degrees C. Gore-Tex, a highly gas-permeable open mesh of Teflon fibrils (78% porosity, 0.2-microns pore size, 75-microns thick), constrains WB to form a thin film without imposing an appreciable gas diffusion barrier. WB layer thickness, measured by isotope dilution, is 1.7 +/- 0.2 microns. WB films are mounted between fiber optics in a gas flow tube for dual-wavelength (536/558 nm) oxyhemoglobin saturation measurements after a step change in PO2. For isocapnic (6% CO2) step changes in PO2 between 0 and 104 Torr, WB O2 uptake half time is 10.4 +/- 0.9 ms; WB O2 release half time is 20.6 +/- 2.4 ms. Half-time values are half of those previously reported. The thin-layer method reduces erythrocyte diffusion boundary layer error and thereby offers an attractive alternative to classical rapid fluid-mixing techniques.
authors.affiliation: Department of Physiology, School of Medicine, State University of New York, Buffalo 14214.
authors.forename: E
authors.initials: E
authors.lastname: Heidelberger
authors.forename: R B
authors.initials: RB
authors.lastname: Reeves
mesh_terms: D000328:Adult; D001693:Biological Transport, Active; D004912:Erythrocytes / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D007700:Kinetics; D008567:Membranes, Artificial; D008954:Models, Biological; D010100:Oxygen / Q000097:blood*; D011138:Polytetrafluoroethylene
chemical_list: D008567:Membranes, Artificial; D011138:Polytetrafluoroethylene; D010100:Oxygen