IN-VITRO EVALUATION OF LIPID MATRICES FOR THE DEVELOPMENT OF A SUSTAINED-RELEASE SULFAMETHAZINE BOLUS FOR LAMBS

The aim of this study is the development of a high-density bolus to be given to lambs in order to release sulfamethazine during 4 days after a single oral administration. The suitability of 12 lipid matrix form ulations was assessed in order to maintain the integrity of the tablet even after complete dissolution of the active substance. The influenc e of both nature and concentration of the lipid excipient on the in vi tro release of sulfamethazine was investigated. The influences of the granulation method and of the compression force were assessed on a for mulation containing Cutina(R) HR as a binding and sustained-release ag ent. Finally, stability tests showed that the in vitro release charact eristics remain unchanged during storage.