CHANGE IN POROSITY PARAMETERS OF LACTOSE, GLUCOSE AND MANNITOL GRANULES CAUSED BY LOW COMPRESSION FORCE

The change in porosity parameters, i.e., total pore volume, porosity p ercentage and pore volume size distribution of lactose, glucose and ma nnitol granules caused by compression with a low force was investigate d. In compression, fragmentation of lactose and glucose granules incre ased total pore volume and porosity percentage, whereas the total pore volume and porosity percentage of mannitol granules was clearly decre ased. This was due to the highly porous structure of mannitol granules , which densified easily in compression. Lactose and glucose granules were shown to resist deformation more. The pore volume size distributi ons of lactose and glucose tablets showed that large pores ( > 14 mu m ) decreased in size. For mannitol tablets, the large pores vanished an d simultaneously the small granule pores ( < 14 pm) reduced in size. T he features of the pore structure of granules were detected in the por e volume size distributions of compressed tablets. Mercury porosimetry , assisted by scanning electron microscopy, was shown to be an adequat e method to evaluate the deformation of granules in compression.