Page 37 - controlled drug delievery
P. 37
Diffusion controlled S.
1-B- Matrix type
• The drug is dissolved or dispersed homogenously throughout an
insoluble matrix.
• The rate of drug release is controlled by diffusion through the matrix.
• The diffusion process in matrix controlled systems is governed by
Higuchi diffusion law:
Mt = (2DACst) 1/2 Mt = K (t) 1/2
