title: Tracer diffusion and unidirectional fluxes.
abstract: Available experimental data have been utilized to examine the effects of cross-coefficients on tracer diffusion and on the estimation of unidirectional fluxes from observations on tracer flow. In free solution or in a nonselective membrane, the interaction between the flows of tracer and the unlabelled substance are small at concentrations of biological interest for the nonelectrolytes urea, alanine, and beta-alanine, and for sodium and chloride ions. Under these conditions, measurement of tracer flow can be used to predict flow of the bulk substance to an accuracy of a few per cent.
authors.affiliation: Biophysical Laboratory, Harvard Medical School, Boston, MA 2115, USA; and Department of Physiology, Yale University School of Medicine, New Haven CT, 06510, USA.
authors.forename: P F
authors.initials: PF
authors.lastname: Curran
authors.forename: A E
authors.initials: AE
authors.lastname: Taylor
authors.forename: A K
authors.initials: AK
authors.lastname: Solomon