"Artificial spores" - hybrid alginate microcapsules with encapsulated yeast cells

The present work describes the fabrication, structure and functional characterization of composite microcapsules containing encapsulated viable yeast cells, fluorescently labeled liposomes and magnetic nanoparticles embedded in a calcium alginate matrix produced by ink-jet printing. The proliferation of the encapsulated cells under favorable conditions (presence of nutrients, temperature) is used as a biological trigger for the disintegration of the microcapsules and the liberation of the encapsulated sub-micron particles. The principle of “artificial spores”, i.e. the possibility to repeatedly stop and restart the cell proliferation process has also been demonstrated. Such biologically triggered release from composite microcapsules is novel and offers potentially interesting applications such as autonomous release of bactericides or fungicides only under conditions that are favorable for microbial growth.