Compression Physics of Pharmaceutical Powders: a Review

Due to various advantages such as high-precision dosing, manufacturing efficiency and patient compliance helped making tablets the most popular dosage forms among all available dosages forms. Compaction, which is an essential manufacturing step in the manufacture of tablets, mainly includes compression (i.e. reduction of volume of the powder under consideration and particle rearrangement) and consolidation (i.e., formation of interparticulate bond to facilitate stable compaction). The success of the compaction process depends not only on the physico-technical properties of drugs and excipients, but also on the instrument settings with respect to rate and magnitude of force transfer. Tablet manufacturing speed and pre/main compression force profile also have an influence on the quality of the final tablet. Mechanical aspects of tablet formation can be studied using, instrumented punches/dies, instrumented tablet punching machines, and compaction simulators. These have potential application in pharmaceutical research and development, such as studying basic compaction mechanism, various process variables, scale-up parameters, trouble shooting problems, creating compaction data library, and fingerprinting of new active pharmaceutical ingredients (APIs) or excipients. Mathematical models, forcetime, force-distance, and die-wall force parameters of tablet manufacturing are used to describe work of compaction, elasticity/plasticity, and time dependent deformation behavior of pharmaceuticals powder under consideration. INTRODUCTION: Pharmaceutical products have historically been administered to the body using a relatively basic drug and excipient combination in suitable dosage form, usually resulting in rapid release and systemic absorption of the drug(s). Different delivery technologies and routes of administration have been used to ensure optimal administration of therapeutic agents. All along the history of pharmacy, oral route has been the most preferred way of drug administration and oral solid dosage forms have been widely used mainly because of their convenience of administration, ease of manufacturing, accurate dosing & patient compliance. Out of powders, granules, pellets, tablets, and capsules, tablets have been the dosage form of first choice in the development of new drug entities and account for some 70–80% of all pharmaceutical preparations . Tablets can be made directly from powders, granules, pellets, or film coated multiple units. The prerequisite, however, is that the material must have good compressibility to form a tablet .