Investigations of tablets prepared from pellets produced by extrusion and spheronisation Part I: The application of canonical analysis to correlate the properties of the tablets to the factors studied in combination with principal component analysis to select the most relevant factors

Abstract

Three different types of pellets prepared by extrusion and spheronisation were mixed and tabletted by a mechanical press and by a tabletting machine. The objective was to prepare tablets of drug containing pellets which would disintegrate into the pellets from which they were made on adding to fluid. Several factors involved in the production of the tablets were analysed by canonical analysis, which identified relationships between the drug loading in the pellets, the proportion of pellets without the drug, the compression pressure used to prepare the tablets, the size of the pellets, the diameter of the die, the concavity of the punch and the density, the porosity, the crushing force to break the tablets, the tensile strength, the friability, the disintegration time of the tablets and the mean dissolution time of the drug. On one hand, the results have shown that the glyceryl monostearate within the pellets interacted with the barium sulphate pellets regarding the disintegration times of the tablets. The glyceryl monostearate was important as a lubricant, whereas the barium sulphate was important for the disintegration of the tablets. The pressure applied and the size of the pellets were not major factors to be considered. However, the shape of the tip of the punch and the diameter of the punches were very important for the properties of the tablets. By combining the Principal Component Analysis with the Canonical Analysis, it was possible to select the variables which had a greater effect on the properties of the tablets.