Microaerosol and Nanoparticle Synthesis for Drug Delivery via Surface Acoustic Wave Atomization

We describe the fabrication of a surface acoustic wave (SAW) atomizer, and show its ability to generate monodisperse aerosol and particles for drug delivery applications. In particular, we demonstrate the generation of insulin microdroplets for pulmonary delivery, and polymeric nanoparticles for one-step rapid encapsulation using SAW devices with resonance frequencies of 8.6 MHz and 19.3 MHz. Insulin droplets around 4 μm were obtained, matching the optimum range for maximising droplet absorption in the alveolar region. Nanoscale polymer particles (130220 nm in diameter) were obtained through a non-equilbrium evaporation and nucleation process, thereby presenting a quick and simple means for nanoparticle synthesis. These results exhibit the feasibility of SAW as a novel method for producing particles and droplets of controlled sizes.