Compaction properties of microcrystalline cellulose and sodium sulfathiazole in combination with talc or magnesium stearate.

The dynamic indentation hardness, tensile strength, bonding index, and brittle fracture index were employed to investigate the compaction properties of a plastic excipient, microcrystalline cellulose, and a brittle drug, sodium sulfathiazole, in combination with different levels of either magnesium stearate or talc. These parameters were also used to quantitate properties of various combinations of microcrystalline cellulose and sodium sulfathiazole in order to illustrate the effects of combining a plastic excipient and a brittle drug. It was shown that the tensile strength, indentation hardness, bonding index, and brittle fracture index for compacts composed of microcrystalline cellulose in combination with either talc or magnesium stearate generally decreased as the amount of talc or magnesium stearate was increased over the concentration range of 0 to 9%. Similar results were observed for admixtures of sodium sulfathiazole in combination with either talc or magnesium stearate. It was also demonstrated that the tensile strength, indentation hardness, and bonding index increased, and the brittle fracture index decreased, as the percent of microcrystalline cellulose was increased in a binary mixture of sodium sulfathiazole and microcrystalline cellulose.