Content Uniformity of Ethinyldestradiol Tablets 10 μG: Effect of Variations in Processing on the Homogeneity After Dry Mixing and After Tableting

Abstract

The effect of numerous processing factors such as mixer geometry and design, power input, time of dry and wet mixing on the content uniformity of tablets containing potent drugs have been studied. Cohesive drug powders and excipients have been used. Results show that pharmaceutically acceptable hamageneity is achieved after dry mixing far 7 hours in the Lödige-Marton mixer. It is shown that there is no significant improvement of homogeneity on increasing the time of wet mixing in excess of 5 minutes, and the rate of breakdown of the drug agglomerates and dispersion of individual particles, under the experimental conditions, is very slow. The high energy input exerted by ball milling markedly improves the homogeneity of the powder mixes and the content uniformity of tablets. After 15 minutes of dry mixing, the state of homogeneity of the powder mix containing cohesive drug powder in minute amounts in cohesive excipient is not influenced by the type of mixer.