A miniaturized surface acoustic wave atomizer with a disposable pump-free liquid supply system for continuous atomization

Surface acoustic wave (SAW) atomization has been found to be a rapid and efficient way for generating micron or submicron aerosols within a controllable fashion. The SAW atomizer is small and light-weighted, attractive for many applications, especially for pulmonary drug delivery and biomicrofluidics. Control the sizes of the aerosols generated by SAW is crucial for successful applications. Unlike the theory applied and published in many SAW atomization works-the size of the aerosol can be tuned by manipulating the driving frequency; -we however found the aerosol size is irrelevant to the driving frequency, but governed by the capillary vibration frequency given by the balance between the acoustic forcing and capillary stress. The self-pumping effect of SAW, on the other hand, leads to the design of a disposable pump-free liquid supply system, which is able to deliver liquids to atomizer automatically for continuous atomization.