Generation of biomaterial particles with controlled dimensions via electrospraying

It is well known that small biomaterial particles can lead to superior properties demanded by advanced applications in tissue engineering. Electrospraying has been considered as a promising approach to prepare fine particles, but reducing the particle size during such jetting process is always challenging. This is because the size of the as-sprayed particles is always limited by the device outlet diameter used. In the study we show that hydroxyapatite (HA) relics of 2 - 3 μm with low standard deviation can be deposited using a large nozzle (diameter of 1100 μm) only by reducing the nozzle tip angle from 90° to 15°. The mechanism of such phenomenon was extensively discussed, and a range of refined HA patterns were successfully prepared using the updated electrspraying configuration. We anticipate our findings to have a significant impact on the research of nanostructured biomaterials with superior properties which are realized by reducing the particle size using a greener electrically-driven processing technique.