Figure 6.2 Release profiles ofantimicrobial agents from various systems. A, unconstrained free diffusion from packaging materials, or fast dissolution from antimicrobial tablets, B, slow diffusion of very low solubility agents from monolithic packaging materials; C, membrane (reservoir) system with constant flux of permeation, slow dissolution from antimicrobial powder/tablets or gaseous agent release from concentrated antimicrobial sachets/tablets with constant volatility in a closed packaging system. Dashed lines and arrows indicate the minimum inhibitory concentration (m.i.c.) of a target micro-organism, and the period of shelf life maintaining the surface concentration over the mic respectively