An Approach to Modeling Protein Release from Lipid Implants

A new approach to modeling protein release kinetics from lipid implants is presented. The recently offered model for prediction of protein transfer out of the lipid implant simultaneously with two water soluble excipients release is improved. Appropriate expressions for concentrations dependent diffusion coefficients are introduced taking into account the initial and current implant porosity. A numerical scheme for solving the arisen highly nonlinear model problem is also developed on the basis of Finite Element (FE) domain approximation and time difference scheme. The new approach and created software are validated using available experimental data for protein release, under different initial content of the drug release modifier. A good correspondence is obtained and a numerical simulation of the effect of the initial implant porosity on drug release profiles is performed.