PHC320H1 Lecture Notes - Lecture 12: Aerosol, Bulk Density, Packing Density
24 Mar 2015
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Document Summary
Particle volume is smaller than bulk volume. Density is a little higher than bulk density. Powder density depends on particle density and flowability. And, another aspect is the outcome of therapeutic agent: if inhalation therapy, requires the particle depositing in the lungs at lower airways. We are going to discuss what determines powder density: powder geometry (not everything packs in the same way). The bulk density can be lower even if we have the same particle density. Here, we are using the concept of physical diameter and density. You want to get an idea of how powder density affects deposition of aerosol: in terms of formulation factors, particle size, density and shape will affect deposition. In addition, patient factors and device factors affect particle deposition in the lungs. This aerodynamic diameter is defined by the multiplication of the physical diameter of the particle by the square root of the particle density.
