Rapid Membrane Emulsification Process for Preparation of Small Microspheres

The optimum controllable particle size prepared by the crossflow or called direct membrane emulsification technique (MET) is between 5 and 100 μm, and smaller particle is difficult to be prepared especially for dispersed phase with high viscosity. The O/W emulsion process has been developed along with rapid MET to prepare hydrophobic microspheres that are sourced from polymer or monomer system. To gain an improved drug adsorption capacity, surface modification strategies have been developed in combination with the preparation of uniform particles by rapid MET. For single emulsion-based particles, the encapsulation of the drug/antigen can only be fulfilled when the solubility property is the same as the inner phase of the emulsion. To extend the applications and improve the drug loading efficiency of particles sourced from different materials, double emulsions like W/O/W or O/W/O together with rapid MET have been developed.