The use of energy indices in estimating powder compaction functionality ofmixtures in pharmaceutical tableting

A series of binary powder blends comprising of microcrystalline cellulose ( Avicel(R) PH101), alpha-lactose monohydrate or theophylline anhydrous were prepared in order to investigate the densification of binary pharmaceutical powder mixes under compaction pressure. It is postulated that the use of d erived energy parameters, as well as various evolved indices, calculated fr om the work expended during the fabrication and/or rupture of a compact can be employed to quantitatively predict the compaction properties of pharmac eutical powder mixes comprised of the same constituents. The relationship b etween the net work of compression normalized to powder volume and the resu lting compact strength For mix constituents can be used to define a pharmac eutical formulation space in which compact mechanical properties can be est imated for other 'virtual mixes' of the same constituents in different prop ortions. The approach is successfully applied to the prediction of the mech anical properties of a ternary mix of these constituents. (C) 1999 Elsevier Science B.V. All rights reserved.