Evaluation of changes in drug particle size during tableting by measurement of dissolution of disintegrated tablets

Three poorly soluble drugs (chloramphenicol, phenacetin and prednisolone) were compressed into tablets of 10% drug content on a physical testing instrument at three different compression pressures. The dissolution profiles were determined by a modification of the U.S.P. method for drug suspensions, granules before compression, disintegrated and intact tablets. By comparison of the dissolution rates for disintegrated tablets with those for granules before compression, or suspensions, it is possible to separate the change in particle size during compression from the pressure-dependent dissolution behaviour of intact tablets. A comparative measurement of dissolution for disintegrated tablets with that for granules provides a useful method for elucidating the particle bonding or cleavage within the tablet during compression.