Drug Release from Viscoelastic Swelling Polymeric Platforms

AbstractWe consider a polymeric spherical platform containing a solid dispersed drug that is in contact with a solvent fluid.While swelling, a non-Fickian sorption of the solvent molecules occurs induced by the effect of the viscoelasticproperties of the polymer. The solid drug in contact with the solvent fluid dissolves and a Fickian release of dissolveddrug takes place. The fluid entrance, the drug dissolution, and the drug release to an external environment are describedby a system of PDEs complemented with an equation for the swelling front, initial, and boundary conditions. The modelincludes the two major factors that govern a swelling process of a polymeric platform within a release medium: thecross-link density and the concentration of the external medium. Energy estimates for the mass of solvent fluid and ofundissolved and dissolved drug in the polymeric platform are established. Numerical simulations that illustrate thetheoretical results are also included.