COMPRESSION ABILITY IMPROVEMENT OF LACTOSE BY RECRYSTALLIZATION - INFLUENCE OF LACTOSE PHOSPHATE CONTENT

A certain batch to batch non-reproducibility of pharmaceutical grade l actose has often been reported. Different causes have been advanced su ch as particle size, specific surface area or crystallinity degree. Th e purpose of this investigation is to study the relative effect of pho sphate content on compressional behaviour. The lactose phosphate conte nt increases when successive recrystallizations are carried out. The c rystals obtained present a higher degree of crystallinity. Surprisingl y, however, compression ability is improved. This could be related to an increase in crystal fragmentation after recrystallization, as indic ated by Heckel's analysis of compression profiles.