Dissolution testing for inhalation formulations

Dissolution testing is one of the most common analyses performed on solid and semi-solid dosage forms, but the industry currently lacks an in vitro test capable of analyzing the dissolution of loose powders such as those used in DPI formulations. For solid dosage forms, this type of testing allows developers to generate data for the comparison and optimization of formulations, and manufactures routinely use these test in quality control (QC) studies such as batch to batch consistency, stability, and detection of manufacturing deviations. A high throughput, cost effective method of understanding how inhalation powders dissolve in the lungs would provide these same benefits to developers and manufacturers of DPI formulations.