BEH.462/3. 962J Molecular Principles of Biomaterials Spring 2003 Hydrogels in drug delivery o What Control of drug release kinetics by hydrogel structure6, o Release from stable hydrogels is controlled by diffusion of solute through the network o Diffusion is described by Fick's second law o Recall the solution to Fick's second law for a semi-infinite slab contacting a perfect sink Egn 2 ID C(XI Increasing time enf(z) solution L o Diffusion of drugs through a network is controlled by the mesh size) Lecture 10-Bioengineering Applications of Hydrogels 6of12BEH.462/3.962J Molecular Principles of Biomaterials Spring 2003 Hydrogels in drug delivery o What Control of drug release kinetics by hydrogel structure6,7 o Release from stable hydrogels is controlled by diffusion of solute through the network o Diffusion is described by Fick’s second law: ∂C ∂ 2 C Eqn 1 ∂t = Dgel ∂x 2 o Recall the solution to Fick’s second law for a semi-infinite slab contacting a perfect sink: Eqn 2 c0 − c(x) =1 − erf    2 tD x    c0 c(x) c0 Increasing time erf(z) solution x o Diffusion of drugs through a network is controlled by the mesh size (ζ) Free s urface Lecture 10 – Bioengineering Applications of Hydrogels 6 of 12