Supplementary Information from The influence of drug solubility and sampling frequency on metformin and glibenclamide release from double-layered particles: experimental analysis and mathematical modelling

To better appreciate the theories used to explain the impact of sampling frequency on drug release from microparticles and overall, the diffusion of active ingredient from two-layered particles into continuously stirred fluid, the mathematical equations used and how they were derived are shown in this supplementary information.