Modelling drug release from composite capsules and nanoparticles
We present a general mechanistic model of mass diffusion for a composite sphere placed in a large ambient
medium. The multi-layer problem is described by a system of diffusion equations coupled via interlayer
boundary conditions such as those imposing a finite mass resistance at the external surface of the sphere. While
the work is applicable to the generic problem of heat or mass transfer in a multi-layer sphere, the analysis and
results are presented in the context of drug kinetics for desorbing and absorbing spherical microcapsules.






