Catalent Pharma has shown the Malvern Spraytec laser-diffraction based particle-size analyser is a useful alternative to cascade-impaction techniques for routine screening of nebuliser formulations.
Researchers from Catalent's respiratory, analytical and biotechnology group, based in North Carolina's Research Triangle Park (US), conducted a cross-validation study on the analyser.
In the Catalent study, which was first presented at Drug Delivery to the Lungs 19 (DDL19, Dec 08, Edinburgh, Scotland) both the Spraytec and the Next Generation Impactor (NGI) were used to determine the particle-size distributions of two formulations delivered from two different nebulisers.
Results from both measurement techniques for the fine-particle fraction - the fraction of a dose that deposits in the lungs - were equivalent, demonstrating that the complementary technique of particle-size analysis by laser diffraction is directly comparable with cascade-impactor measurements.
The use of particle-sizing techniques is critical in understanding inhaled drug and device performance.
While cascade-impactor testing remains essential for validation and submission purposes, the results of the study show that laser diffraction can be used for routine testing.
It offers fast, efficient access to the information needed to quantify device/formulation performance and to assess the ranges available for safe and effective development as encouraged by QbD.
As such it is a valuable tool for cutting the costs and timelines associated with inhalation-product development.
Spraytec offers the robust operation and rapid data-acquisition needed to reliably measure aerosolised droplet-size distributions in real-time, during spraying.
Measurements can be carried out rapidly and over a broad range of particle sizes (typically 0.1-2000 microns), delivering detailed dynamic information.
