Selection of Silica Type and Amount for Flowability Enhancements via Dry Coating: Contact Mechanics Based Predictive Approach

ConclusionSignificant flow enhancements were achieved at 50% SAC, validating previous models. Most uncoatedvery cohesive powders improved by two flow categories, attainingeasy flow. Flowability could not be predicted for both the uncoated and dry coated powders via particle size alone. Prediction was significantly better using Bond number computed via the mechanistic multi-asperity particle contact model accounting for the particle size, surface energy, roughness, and the amount and type of silica. The widely accepted 200  nm surface roughness was not valid for most pharmaceutical powders.
Source: Pharmaceutical Research - Category: Drugs & Pharmacology Source Type: research