Relationship between breaking force and pore structure of lactose, glucose and mannitol tablets

Abstract

The aim of this study was to determine the relationship between the breaking force of lactose, glucose and mannitol tablets and the pore structure characterised by numeric porosity parameters: total pore volume, total pore surface area, mean pore diameter, median pore diameter and volume-size distribution of pores, obtained by mercury porosimetry. A clear overall relationship was found between breaking force of tablets and the median of the cumulative pore volume-pore diameter curve and pore volume-size distribution. The dependence of the breaking force on total surface area of pores was less evident. Fragmentation of granules contributes to the creation of large intergranular and intragranular pores, and further fragmentation and plastic deformation of the primary particles contributes to their reduction in number and size. According to pore volume-size distributions, the decrease in the volume of large pores and the shift of the maximum for volume-size distribution towards smaller pore diameter were related to the increased breaking force of tablets.