Mathematical Treatments and Early Models of Skin Permeability
(3.1) where the terms used are shown in Fig. 3.1. This expression indicates that, at long times, there is a steady-state flux of (A 1 k 12 k 23)/(k 21 + k 23)…
Finite-Dose Models of Transient Exposures and Volatile Formulation Components
Fig. 8.1 Schematic representation of flux and cumulative absorption profiles for a finite-dose application to human skin (© Williams (2003), used with permission) Designing in vitro experiments that accurately reflect this…
Squiggly Lines and Random Dots—You Can Fit Anything with a Nonlinear Model
(7.1) where (7.2)is the permeation coefficient of the lipid fraction of the stratum corneum, (7.3)is the permeation coefficient of the protein fraction of the stratum corneum, and (7.4)where K ow…
Other Approaches to Modelling Percutaneous Absorption
(6.1) where P is the partition coefficient of the permeant between the membrane and the donor vehicle; C is the concentration (in this case, the solubility) of the permeant in…
Algorithms for Estimating Permeability Across Artificial Membranes
(5.1) where J mss is the maximum steady-state flux (μ mol/s/cm2); J mss is the maximum steady-state flux (μ mol/s/cm2); e H is the charge value on a hydrogen with charge higher…
Skin Structure and Physiology
Fig. 1.1 Schematic diagram of the skin (© Williams (2003), used with permission) On average, human skin contains 40–70 hair follicles and 200–250 sweat ducts per square centimetre of skin. The…
The Devil is in the Detail…
Fig. 9.1 A comparison of experimental permeability for a series of captopril carboxyl ester prodrugs with the QSAR models of skin permeability proposed by Moss and Cronin (2002), Potts and Guy…
Conclusions and Recommendations for Model Development and Use
Essential properties Desirable properties A well-defined and readily measurable endpoint (i.e. permeability, k p, or flux (J max or J ss) Do not extrapolate or use the model beyond its…
Methods for the Measurement of Percutaneous Absorption
Fig. 2.1 Examples of commonly used diffusion cells (© Williams (2003), used with permission) There are two main types of diffusion cells: static and flow-through cells. The vast majority of in…
Allergenic Sensitisation Mediated by Wolfberry
Classification of plant food allergens Superfamily Family Biological function Common allergens Prolamin 2S albumins Seed storage Wheat, peanut (Ara h 2, Ara h 6, Ara h 7), walnut (Jug r…
