Fig. 1.

a) Photograph of an aqueous-two-phase system of dextran-sulphate (bottom) and fluorescein conjugated alginate (top). b) Schematic representation of microparticle synthesis (top) supported by fluorescence microscopy micrographs (bottom). Alginate is labelled with fluorescein (green) and the PA is labelled with rhodamine (red). c) SEM micrographs of dried microparticles coated with a PA layer. d) Schematic representation of the final microparticle. e) Synthesis of alginate derivatives 1, 2 and 3.