title: Effects of temperature and pressure during compression on polymorphic transformation and crushing strength of chlorpropamide tablets.
abstract: The effects of temperature on the polymorphic transformation of chlorpropamide during compression and on the physical properties of the tablet have been investigated. A heater and liquid nitrogen pool were mounted on the die of a single punch eccentric tableting machine, and the die temperature was controlled by a thermocontroller. A tableting machine with two load cells (upper and lower punches) and a non-contact displacement transducer were used to measure compression stress, distance and energy. The X-ray diffraction profiles of the deagglomerated compressed sample powder were measured to calculate the polymorphic content. The amount of form C transformed from form A at 45 degrees C was about twice that at 0 degree C with the same compression energy. The amount of form A transformed from form C by compression at 45 degrees C was almost the same as that at 0 degree C. This suggests that the mechanochemical effect of form A depended on the compression temperature, but that of form C was independent of temperature. The crushing strength of tablets of form A was about twice that of form C, even at the same porosity. The plots of log (crushing strength of tablet) against porosity of form A tablets compressed at 0 and 45 degrees C were linear with the same slope; the slope for form C tablets compressed at 45 degrees C was less than that at 0 degree C.
authors.affiliation: School of Pharmaceutical Sciences, Showa University, Tokyo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Matsumoto
authors.forename: N
authors.initials: N
authors.lastname: Kaneniwa
authors.forename: S
authors.initials: S
authors.lastname: Higuchi
authors.forename: M
authors.initials: M
authors.lastname: Otsuka
mesh_terms: D002626:Chemistry, Pharmaceutical; D002747:Chlorpropamide; D011312:Pressure; D013607:Tablets; D013696:Temperature
chemical_list: D013607:Tablets; D002747:Chlorpropamide