Design and Evaluation of an Oral Floating Matrix Tablet of Salbutamol Sulphate

Purpose: To develop floating matrix tablets of salbutamol sulphate using ethyl cellulose and acrycoat S-100 as polymers, and sodium bicarbonate, citric acid and tartaric acid as gas generating agents.
Methods: Twenty four formulations were prepared and segregated into four major categories, A to D. The floating tablets were prepared by wet granulation technique, and the granules were compressed at a pressure of 50 kg/cm². The tablets contained drug, ethyl cellulose and Acrycoat S-100 (as releaseretarding polymers), sodium bicarbonate, citric acid and tartaric acid (as gas formers) as well as various additives. The tablets were made by wet granulation technique. The formulations were evaluated for in vitro buoyancy, dissolution and in vitro drug release.
Results: All the formulations fulfilled the essential requirements for good floating systems. Formulation F8, containing citric acid and sodium bicarbonate, showed lower lag time and longer floating duration than the formulations containing only sodium bicarbonate. Formulation F8.2 (which contained citric and tartaric acid at a ratio of 1:1) showed longer floating duration (9 h) than F8. As the concentration of sodium bicarbonate increased in formulation F8.2, drug release decreased while floating duration increased.
Conclusion: Of all the 24 formulations, the one containing tartaric acid and citric acid in ratio 1:3 and 12 mg sodium bicarbonate showed the highest floating duration and least lag time.

Keywords
Salbutamol sulphate, Ethyl cellulose, Acrycoat S-100, Sodium bicarbonate, Citric acid, Tartaric acid