(1) Microspheres have many applications in medicine, with the main uses being for the encapsulation of drugs. The target area could receive drug loaded microspheres either by passive means (trapping by size) or by active means (magnetic targeting) and slowly release the encapsulated drug over a desired time period, the extent of which is determined mainly by the drug's biological half-life. The drug distribution and final destiny of the microspheres is mainly depends on their size and surface charge.
(2) complex particles can be created by using concentric nozzles from two liquids; or from a liquid and a gas resulting in the production of hollow spheres.
The formation of complex particles is shown in the figure on left. In this process two different types of disperse phases can be flown. In this figure if we use air/gas as disperse phase then the formation of hollow micro spheres will take place. We can also use two different types of drugs as disperse phases 1 & 2 and can make very effective medicines. In a particular treatment, if we want to release two drugs one after the other in some living body then this process is very helpful. Initially, outer-layer of the drug will start to release from the droplets and thereafter will be absorbed by the body. When the absorption of outer layer gets completed, the release of the encapsulated drug initiates.**************************************************************************************************************************************************************************************************************************
