Analysis of intestinal membrane permeability by transport equation
1988 Volume 3 Issue 3 Pages 359-367
Details
1988 Volume 3 Issue 3 Pages 359-367
The membrane permeability of rat intestine was estimated by using the transport equation in cylindrical coordinate.
?? +Vz ?? =Dr ?? r ?? −PwCw
Four fluid flow profiles were assumed. 1) Mixing tank model, 2) Complete radial mixing model, 3) Plug flow model, and 4) Laminar flow model. Laminar flow model that has a parabolic velocity profile (Vz=Umax{1-(r/R)2}) was found to be the best to correlate with the drug concentration change in the intestine. The differential equation was solved to obtaine the exit cup-mixing concentration profile at non-steady state after pulse input. The finite difference analysis and least squares method were used to estimate the permeability coefficient and the diffusion coefficient, and to simulate the concentration distribution in the intestine.
