New experimental work using the Sysmex FPIA-3000 and Spraytec systems from Malvern Instruments, highlights the complementary nature of particle characterization by image analysis and laser diffraction respectively, when applied to the development of pharmaceutical nebulizers. Nebulizers produce an easy-to-inhale aerosol cloud from a liquid drug suspension and are used increasingly for the delivery of a wide range of locally acting and systemic drugs. A published article detailing the work is freely available from the Malvern Instruments website.
In responding to the demands of Quality by Design, developers of inhaled products and inhalation systems require fast, reliable analytical instruments that make a direct contribution to fine-tuning formulation and device performance. Particle characterization plays a critical role in optimising inhalation systems for efficient and effective delivery of an appropriate respirable dose.
Automated image analysis using the Sysmex FPIA-3000 provides size and shape information of particles in suspensions, while the Spraytec’s laser diffraction technology allows real-time measurement of droplet size distributions within sprays. Together the two techniques give detailed insight into device and formulation, interactive behaviour, and the factors influencing performance.
In a nebuliser, the characteristics of droplets produced during aerosolisation are formulation dependent and affect deposition profiles. In the case of suspension formulations, image analysis can be used to directly investigate critical formulation attributes, including the tendency of the drug particles to agglomerate, since the state of dispersion may be detected on the basis of shape. Analysis is complete in minutes.
The mechanics of droplet deposition in the respiratory tract demand that particles in the aerosol cloud are less than 10 microns in diameter, with 5 microns or below achieving penetration into the lung. Spraytec allows rapid assessment of the impact of variables that affect droplet size, such as formulation properties and nebulizer driving gas flow rate.
To download the full article visit http://www.malvern.com/nebulizers