Generation of large droplet aerosols within microbiological containment using a novel flow-focussing technique

Flow-focussing technology was harnessed to enable generation of large droplet aerosols within high-level microbiological containment. The Collison nebuliser and flow-focussing aerosol generator (FFAG) produced aerosols from distilled water with average mass median aerodynamic diameters (MMAD) of 4.19 and 11.93 mu m, respectively. The medium type [water, phosphate buffered saline (PBS) or microbiological broth] had minimal effect on the droplet size generated by the FFAG. The FFAG can be modulated to generate reproducible aerosols with a wide range of MMADs (9-105 mu m). The number of particulates (i.e. fluospheres) contained within the droplets increased as the MMAD increased from 12 to 50 mu m. The technology described can be used for the exposure of small-animal models to large droplet aerosols (> 10 mu m) and has applications in healthcare, pharmaceutical, agricultural and biodefence environments.