Page 39 - controlled drug delievery
P. 39
Formulation of Matrix Diffusion type
1. Insoluble matrix forming materials include:
i. Insoluble polymers e.g. Ethylcellulose, Eudragit RL & RS,
polyvinyl acetate ,polyvinyl alcohol (PVA), polyethylene (PE)
ii. Fatty compounds e.g. Carnuba wax, microcrystalline wax
2. Channeling agents e.g. NaCl, sugars, polyols
3. Solubilizers & pH modifiers
4.
The release rate from inert matrix can be modified by varying:
i.
ii.
iii.
