Preparation and characterisation of biopolymeric volvox-like spheres: a feasibility study

This feasibility study presents the implementation of an integrated preparation system for the production of biopolymeric volvox-like microspheres, where an outer microsphere (400-560--m in diameter) encloses smaller microspheres (about 20--m in diameter). The preparation employs an ultrasonic extrusion system and a high-voltage electrostatic field. Resistance to agitation tests have shown that higher the concentration of alginate, higher the percentage of microspheres that can retain their shape (65- at 3- alginate). The microspheres- architecture presented here provides a new insight into how microspheres can be re-designed for new applications, where the enclosed smaller microspheres are not in contact with the outer environment, therefore can be protected until the outer microsphere is degraded or ruptured.