Agglomerate strength and dispersion of pharmaceutical powders

Colistin Powders with High Aerosolisation Efficiency for Respiratory Infection: Preparation and In Vitro Evaluation

“…In an environment near or above the critical humidity (>75% RH in this case), the absorbed water may dissolve the particle surface and move to the contact region between particles because of capillary forces . After re‐entering a dry condition, water will be removed from the powder but solid bridges form, resulting in powder caking observed at 90% RH in the present study (Fig. a).…”

A digital workflow from crystallographic structure to single crystal particle attributes for predicting the formulation properties of terbutaline sulfate

“…5 crystals having a particle size of 70-140 μm. [8][9][10] Due to their small particle size, respirable API particles display highly cohesive and adhesive behaviour readily tending either to form agglomerates 11 or to adhere to the surfaces of excipient materials, manufacturing process equipment or inhaler device components. [12][13][14][15] Agglomerated or adhered drug particles must be re-dispersed effectively upon inhalation in order to be suitable for lung deposition.…”

A view on the less-than-rational development of drug delivery systems – The example of dry powder inhalers

“…Research on the agglomerate strength of solid dosage forms, such as tablets, commenced in 1960s, long before the interest in powders for inhalation [80]. In the context of oral solid delivery, a simplified model was proposed to describe tensile strength of a powder [81] and recently this theory was used to provide a mechanistic understanding of the deagglomeration of powders during aerosolisation [74,82]. The approach assumes a homogeneous powder bed, whereas it is actually heterogeneous.…”