The effects of polymorphism, particle size and compression pressure on the dissolution rate of phenylbutazone tablets

Abstract

The dissolution rate of phenylbutazone from tablets after disintegration has been used to determine whether the drug particles underwent crushing or bonding during compression. Two polymorphic forms of the drug were used and the predominant effect for high drug concentration (60%), during compression was dependent upon the original particle size of the drug and its polymorphic form. With a low drug concentration (10%) in the tablet, the diluent protected the drug particles from bonding together. The particle size change of the drug during compression was affected by the nature of the diluent present. Lactose had an abrasive action on Form A phenylbutazone compared with Avicel but had little effect on the more ductile Form B. When the contact time of compression was decreased from 29 to 0.26 s, the 6 microns particles of drug showed less bonding at the shorter time (faster rate of compression) but the effect observed with the larger particles was independent the compression rate.

Effect of Compression Force on Agglomeration of Micronized Active Pharmaceutical Ingredients: Techniques to Prevent API Agglomeration During Compression

“…Tuladhar et al described the change in the API particle size during compression was affected by nature of the diluents present in the formulation and also found that the agglomeration of fine particles during compression was independent of rate compression. 95 Highly homogenous blend for highly cohesive micronized API can be achieved by blending the formulation with highly porous and freely flowing diluents. However, some diluents with highly indented surface may entrap the micronized drug and forms pockets of agglomerates which hamper the dissolution.…”