Inhaled Dissolution Testing - Dose Collection

At present, there are no official dissolution test methods described that are applicable to inhaled products. One of the main problems facing the developers of such methods is the identification and segregation of that part of the total emitted dose actually reaching the target site (as opposed to the whole dose) in a form readily adaptable to conventional dissolution testing techniques.

The NGI Dissolution Cup and Membrane Holder is a modification of the standard NGI collection cup which allows size-fractionated particles from an aerosol cloud to be collected and then tested in a conventional dissolution tester in a manner similar to the Paddle over Disc Method described in USP Method 5 and Ph.Eur. 2.9.4.

A similar technique can be employed using the Andersen Cascade Impactor, in this case, by applying a 76 mm polycarbonate filter to the appropriate collection plates prior to analysis, such that the drug is captured directly on the membrane, and then sandwiching the inverted membrane between the glass and PTFE surfaces of the Watchglass/PTFE Assembly normally used for transdermal patches.

For comprehensive product details, specifications and part numbers, please request a copy of our brochure “Quality Solutions for Inhaler Testing”.