New inhalation cell for Malvern Spraytec aids development of aerosol drug delivery devices

Malvern Instruments has introduced an Inhalation Cell accessory for its new generation Spraytec laser diffraction particle size analyzer.

Aerosol delivery is becoming increasingly important for a wide variety of therapeutic materials, providing a means of rapid drug delivery with high bioavailability. The Spraytec’s new Inhalation Cell is designed to support pharmaceutical development by enabling the rapid characterization of systems such as dry powder inhalers (DPIs), metered dose inhalers (MDIs) and nebulizers. Measurements can be carried out under fixed or varying flow rate conditions, so the system is ideal for the optimization of API delivery by the inhalation route.

The new Inhalation Cell fits easily on to the Spraytec optical bench and is readily dismantled for cleaning. Once the cell is fitted, all the benefits of the Spraytec system become available to inhaler developers, delivering real-time, high-speed particle size measurements for the complete characterization of continuous and pulsed spray events. With a data acquisition rate of 10 kHz – in practice a 100-microsecond time resolution – it allows highly accurate analysis of the dynamics of spray atomization and dispersion, so that even the rapid changes in particle size that take place during inhaler operation can be followed.

If required, the Inhalation Cell can be used in-line with conventional impaction techniques and is fully compatible with the associated flow control systems, allowing correlation with traditional methods. However, it offers the benefits of significantly higher measurement rates - several hundred per day compared with six for conventional techniques - enabling the rapid screening of formulations for correct dispersion performance. It also provides greater insight into particle formation and dispersion. Since laser diffraction measurements are independent of flow rate, the Spraytec with Inhalation Cell allows the measurement of particle size distributions during the operation of a device using model patient profiles, thus providing a more-realistic mimic of real-life performance.

The Spraytec system is exceptionally easy to use, with built-in SOP wizard aiding method definition and transferability, and offering single-click operation. Full lifecycle documentation, following GAMP guidelines, provides complete design traceability; IQ/OQ documentation is provided for validation plans; and software provides technical compliance with the requirements of 21 CFR Part 11.