Excipient crystal morphology

Most drug and inactive excipients used in tablet formulation are in the solid state as amorphous powder or crystals of various morphological structures. There may be substantial differences in particle size, surface area, crystal morphology, wetting, and flowability as well as many physical properties of drug, excipients, and their blends [16]. Table 12 describes common micromeritic topics important to pharmaceutical preformulation. 

Knowledge of crystal morphology and ways to control and predict the morphology of drugs and excipients could prove invaluable in formulation and product... 

Ketoprofen and 17 commonly used excipients were chosen as the probe systems for this study [81]. The molecular modelling has two parts prediction of crystal morphology followed by the prediction of binding energy of a probe molecule on the surfaces of the ketoprofen crystal. Three conformers for each of these excipients (probe molecules) were taken into consideration. For those excipient molecules which have more than one molecule in the asymmetric unit (e.g. sorbitol and a-lactose monohydrate), both the complete asymmetric unit as well as three conformers of a single molecule were considered as the probe conformations for the systematic search study. For those excipients that are polymers, a representative monomer unit was used as a probe molecule. 

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