Straightforward biodegradable nanoparticle generation through megahertz-order ultrasonic atomization

Simple and reliable formation of biodegradable nanoparticles formed from poly-epsilon-caprolactone was achieved using 1.645 MHz piston atomization of a source fluid of 0.5% w/v of the polymer dissolved in acetone; the particles were allowed to descend under gravity in air 8 cm into a 1 mM solution of sodium dodecyl sulfate. After centrifugation to remove surface agglomerations, a symmetric monodisperse distribution of particles phi 186 nm (SD=5.7, n=6) was obtained with a yield of 65.2%