Assessing predictability of packing porosity and bulk density enhancements after dry coating of pharmaceutical powders

Ability to predict the porosity, and its reduction after nano-silica dry coating, based on Bond number cohesion force estimated via multi-asperity contact model was examined for twenty different pharmaceutical powders. A new first order estimates of bulk density improvements coating found be reasonably predictive despite variations in size (10–225 μm), particle distribution, aspect ratios (1–3.5), material density, dispersive surface energy. For porosity prediction numbers, Microcrystalline Cellulose (MCC) excipients were outliers, regardless (20–200 μm). Analysis their shape, morphology specific areas (SSA), indicated that compared other powders, MCCs had highest SSA equivalent spheres high macro-roughness, while having ratios. This unique characteristic made them effectively more cohesive leading poor packing independent size, which is line with previous simulations.