Nebulisation Method

A method for the preparation of nebulised droplets, the method including the steps:

• providing a device having an acoustic wave interaction surface with an array of cavities opening to the acoustic wave interaction surface;
• providing an acoustic wave transducer adapted to generate and propagate acoustic waves to the acoustic wave interaction surface;
• providing, in the cavities, a liquid for nebulisation;
• operating the acoustic wave transducer at a first input power to generate and propagate acoustic waves to the acoustic wave interaction surface to interact with the liquid in the cavities to produce nebulised droplets having a first aerosol particle size distribution;
• and
• operating the acoustic wave transducer at a second input power, greater than the first input power, to generate and propagate acoustic waves to the acoustic wave interaction surface to interact with the liquid in the cavities to produce nebulised droplets having a second aerosol particle size distribution having a larger mass median aerodynamic diameter (MMAD) than that of the first aerosol particle size distribution.