Alginate hydrogel microspheres and microcapsules prepared by spinning diskatomization

Our spinning disk atomization (SDA) can, relative to other existing techniq ues, produce micron-sized particles with very narrow size distribution. The aim of this work is to present this technology for the production of algin ate microspheres and microcapsules. We atomized and gelled aqueous alginate solutions into very narrowly dispersed microspheres with sizes ranging fro m 300 to 600 mu m. Here, the interest is to produce, at high rate, particle s of a given size with a narrow size distribution and also to show a new me thod of encapsulation using SDA. The viscosity and flow rate contributions in the drop formation is qualitatively analyzed to show how they affect dro plet size. In addition, a technique for high degree of encapsulation is pre sented in which yeast is used as a model system. The production of yeast-lo aded microspheres by SDA shows the potential of the technique for biotechno logy applications. (C) 2000 John Wiley & Sons, Inc.