Cup Coating (NGI)
Particle bounce and re-entrainment can be a particular problem when using cascade impactors to measure the aerodynamic particle size distribution (APSD) of orally inhaled and nasal drug products.
Particle bounce is a phenomenon whereby the particle impacts against the collection surface appropriate to its size but rather than adhering to that surface “bounces” back into the air stream whereupon it is re-entrained and passes to a lower stage than that intended.
The normal method of addressing this problem is to coat the collection surfaces with a tacky viscous material such as, for example, glycerol or silicone oil.
The amount, uniformity and method of application are critical parameters within the coating process.
The NGI Cup Coater has been designed as a standardised approach to this problem and eliminates many of the variables inherent in this process.
For comprehensive product details, specifications and part numbers, please request a copy of our brochure “Quality Solutions for Inhaler Testing”.