Preparation and in vitro dissolution of salbutamol sulphate microcapsules and tabletted microcapsules.

Salbutamol sulphate is a sympathomimetic amine having a rather short plasma half-life. Aiming to achieve sustained release of this drug through microencapsulation, the coacervation method with a 1:1 core-shell ratio was used. In vitro release rate experiments were performed on the microcapsules prepared using ethyl cellulose as the coating agent and compared to the results of intact drug, the tabletted microcapsules and a commercial tablet. The release rate of salbutamol sulphate could be controlled through microencapsulation. The time for the 50% release of the drug was 15 and 90 min for the tabletted microcapsules and microcapsules respectively. The specific surface area of the intact drug was 0.35 m2/cc while it reduced to 0.06 m2/cc after encapsulation.