RDD Online LLC has acquired the right to sell Dosage Unit Sampling Apparatus (DUSA), also known as the Delivered Dose Sampling Apparatus, and related accessories for pressurized metered dose inhalers and dry powder inhalers, developed by Nephele Enterprises. The agreement also permits RDD Online to sell Nephele’s patented mixing inlets, which allow representative aerosol sampling and constant airflow though a cascade impactor while flow profiles through an inhaler are varied.

Nephele Mixing Inlet

The Nephele Mixing Inlet (NMI) is designed to permit a cascade impactor to be operated at a constant flow rate (e.g. 60 LPM) while allowing a lower fixed or variable flow rate to pass through the inhaler device. New designs are now available for use with both the Andersen Cascade Impactor (ACI, the Nephele II) and the Next Generation Impactor (NGI, the Nephele III), although RDD Online can still supply the original Nephele Mixing Inlet via special order. These units are in increasing demand since they lend themselves to use with realistic throat models (including those developed by Virginia Commonwealth University) when investigators want to sample aerosol at various simulated inhalation flow rates.

Dosage Unit Sampling Apparatus (DUSA)

The delivered dose is the mass of drug emitted from the mouthpiece of an inhaler device when a dose is released according to prescribed testing conditions. It is considered to be the best estimate of the dose likely to be delivered to a patient, when the test is performed as described in official compendia. Delivered dose uniformity testing is described in both the European Pharmacopeia (<0671> Preparations for Inhalation) and the United States Pharmacopeia (Chapter <601> Aerosols, Nasal Sprays, Metered—Dose Inhalers, and Dry Powder Inhalers).

The compendial Dosage Unit Sampling Apparatus (DUSA) for metered dose inhalers (MDIs) was originally developed by Charles Thiel, at 3M Pharmaceutical Division.

A larger compendial sampling apparatus, the Dosage Unit Sampling apparatus for dry powder inhalers (DPIs) was based on a similar design first proposed by Peter Byron and Michael Hindle (Virginia Commonwealth University) in which the area of the filter was increased to allow for higher flow rates during testing. In the DPI DUSA an optional pressure tap is included to allow the user to define the pressure drop across the inhaler as a function of the test flow rate.

All equipment is supplied according to our Terms and Conditions of Sale.