Page 38 - controlled drug delievery
P. 38

Diffusion controlled S.
                       1-B- Matrix type

• The diffusion process in matrix controlled systems is governed by
   Higuchi diffusion law:

Mt = (2DC0Cst) 1/2  Mt = K (t) 1/2

Mt : Amount of drug released per unit area exposed to the release
    medium at time t

D: Diffusion coefficient of the dug
C0 : Initial total drug concentration in the matrix
Cs : Saturation solubility of the drug
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