Antisolvent vapour precipitation of droplets with multi-components: Non-soluble encapsulation and simultaneous precipitation of soluble materials

A new antisolvent vapour precipitation technique was developed which enables the production of a large amount of micro spheres from a single droplet. This work explores the potential of this technique for encapsulation of oil and in precipitating multi-component solutes from a droplet. Experiments were undertaken on the single droplet drying rig in Monash University, modified to incorporate antisolvent vapour. Using ethanol vapour, lactose micro particles with spiky surfaces were formed. Oil-infused lactose micro particles were also observed delineated by the smooth surfaces analogous to that of full cream milk. Precipitation of multi-component solutes resulted in partial segregation of the protein and lactose. Precipitated particles with different proportions of protein and lactose exhibited contrasting particles. Particles with higher protein content resulted in smaller particle sizes.