J. Conceição^1,, M. Estanqueiro¹, M. H. Amaral¹, J. P. Silva¹, J.M. Sousa Lobo¹

The physical properties of pharmaceutical powders/granules are very important in the development of oral solid dosage forms. The aim of this paper was, in a first stage, to carry out an evaluation of the flow properties (angle of repose, flow time, compaction capacity, compressibility index, Carr index and Hausner ratio) of technological or primary excipients of tablets (microcrystalline cellulose and dibasic calcium phosphate dihydrate) which behave differently during compaction, either pure and in binary mixtures, whose composition varied between 20% (w/w) and 80% (w/w) at intervals of 20% (w/w). In a second stage, using an instrumented eccentric tableting machine, energies and exerted forces during compaction of these materials were measured and the compressibility curves were registered. In addition, plasticity index and lubrication coefficient were calculated and weight uniformity, thickness, hardness and tensile strength of the manufactured tablets were also evaluated. The obtained results demonstrated that the binary mixtures and the pure excipients showed similar flow properties. On the other hand, the obtained tablets with the plastic excipient had lower values of exerted force by the upper punch and apparent net energy, and higher values of plasticity index and time periods of the force/time compression profiles.

excipients, binary mixtures, flowability, compaction, tablet instrumentation