Utilization of the Solids Processor for Preparation of Tablet Granulations

Abstract

Various factors relating to the use of vacuum tumble dryers for the preparation of tablet granulations were studied.A dryer was employed (the 1-cu.ft.solids processor) which has a working capacity of 15-18 kg.for most pharmaceutical granulations.A typical process involves the wetting of the substrate with a drug solution and then drying at a predetermined temperature and vacuum.It was found that uniform drug distribution for low-dose tablet formulations could be obtained.Drying rates were determined for spray-dried lactose and dicalcium phosphate dihydrate at two temperatures and three tumbling speeds.Drying times varied from 35 to 60 min.A series of modified direct compression formulations was studied in which microcrystalline cellulose was used at two levels; two lubricants, calcium stearate and stearic acid, were employed; and lubricant addition was carried out by two methods, internal and external.The effects of these factors on tableting characteristics were monitored by an instrumented tablet machine (Stokes BB-2), and the final physical properties of the tablets were determined.A series of antacid granulations was prepared in which the influence of mixing time and the amount of granulating fluid was varied.The resulting granulations and tablets were characterized as described above.