Rayleigh breakup aerosol spray devices: Investigations into their toxicology and aerobiology applications

The development of aerosol generation and delivery devices for inhalation exposure of test subjects, whether human, animal or in-vitro cell or organoid culture, present substantial challenges. Notably, species specific requirements for therapeutic respiratory dosing leads to technologies that deliver selected size aerosols in the liters per minute range. Particle sizes ranging from sub-micron to greater than 10 microns are sought. Practical and affordable devices are the goals. From the polydisperse Collison pneumatic nebulizer to the spinning top monodisperse aerosol generator, a family of non-pneumatic devices have emerged. Notable is the vibrating mesh generator employing high frequency oscillations to create highly concentrated aerosols,
New to this field is Rayleigh breakup technology found in a one fluid nozzle that uses elevated pressure to force liquids through a series of micron sized openings. Crafted using computer chip technologies, these silicon wafers with defined pores are generated by stereolithographic methods. From this, a variety of devices for aerosol spray applications have been created. CH Technologies has adapted some of these products for use in aerobiology and inhalation toxicology applications. Notably transport as well as dilution of freshly generated aerosols in a cost effective and affordable research environment are to be presented.
Experiments were undertaken with 4-micron pore size grids to generate near monodisperse aerosols in 8-micron (by mass) size range. Research continues with pores in the 1.75- and 1.9-micron sizes to yield aerosols in the less than 5-micron (by mass) size range.