title: Bulk characterization of pharmaceutical powders by low-pressure compression II: effect of method settings and particle size.
abstract: The aim of the present study was to investigate the effect of punch and die diameter, sample size, compression speed, and particle size on two low-pressure compression-derived parameters; the compressed density and the Walker w parameter. The excellent repeatability of the low-pressure compression method allowed small effects of variations in punch and die diameter and sample size to be demonstrated on a high significance level. Changing the compression speed, however, did not cause a significant effect in the compressed density, whereas a decrease in w was seen. The effect of particle size was studied by compressing and tapping different grades of calcium carbonate, lactose, and microcrystalline cellulose. The low-pressure compression-derived parameters were compared to tapped densities and to Compressibility Indexes obtained by tapping volumetry. Even though the relationship between particle size and the low-pressure compression-derived parameters appeared to be more complicated, a similar trend was observed. It was concluded that the low-pressure compression method provides a useful alternative to the more sample-consuming methods providing flow-related information.
authors.affiliation: Department of Pharmaceutics, The Danish University of Pharmaceutical Sciences, Universitetsparken 2, CPH-2100, Denmark.
authors.forename: Arne Hagsten
authors.initials: AH
authors.lastname: Sørensen
authors.forename: Jørn Møller
authors.initials: JM
authors.lastname: Sonnergaard
authors.forename: Lars
authors.initials: L
authors.lastname: Hovgaard
mesh_terms: D000465:Algorithms; D004339:Drug Compounding / Q000379:methods*; D005079:Excipients; D007834:Lasers; D008855:Microscopy, Electron, Scanning; D010316:Particle Size; D011208:Powders; D011312:Pressure; D015203:Reproducibility of Results
chemical_list: D005079:Excipients; D011208:Powders