I consider this chapter to be one of the most important chapters in the book. We know that a drug has to form a solution in an aqueous medium if it will be administered IV. We also know that drugs can cross membrane barriers only as molecular dispersions. Therefore, they can get absorbed and distributed in the body only if they mix and dissolve in biological fluids. Drug dissolution and membrane crossing occur by diffusion. Through nice descriptions and activities related to the phenomenon of diffusion and osmosis, you will understand the process of dissolution and you will relate it to drug absorption and distribution into tissues. You will correlate the physicochemical properties of drugs to their ability to cross cell plasma membranes and will understand the effect of food and gastrointestinal motility on drug absorption.
KeywordsSolution Molecular dispersion Absorption Dissolution Convection Advection Diffusion Diffusion coefficient Noyes–Whitney equation Concentration gradient Permeability Osmosis Flux Drug transport Transporters
- M.L. Raff, Principles of Physical Chemistry, 1st edn. (Prentice Hall, Upper Saddle River, 2001)Google Scholar