Encapsulation of living cells into sporopollenin microcapsules

Abstract

We demonstrate that living cells can be encapsulated inside sporopollenin microcapsules derived from Lycopodium clavatum. To encapsulate large objects like cells, the sporopollenin particles are compressed into a pellet which forces their trilite scars to open up. Our method involves exposing a sporopollenin pellet to an aqueous suspension of cells in the presence of a surface active agent which facilitates the capillary suction of the cells suspension inside the compressed sporopollenin and its “re-inflating” and closure of trilite scars. We demonstrate that the viability of the cells is preserved after the encapsulation in the sporopollenin capsules which contain a significant amount of entrapped cells and show biological activity when placed into a culture medium. Since the sporopollenin nanopores allow nutrient transport across the capsule wall, it could be used for controlling the rate of in situfermentation reactions or as bio-reactors. We also show that sporopollenin can be loaded with magnetic nanoparticles and live cultures simultaneously which would allow remote manipulation, fixation, removal or potentially targeted delivery of such bio-microreactors. The encapsulation of living cells inside sporopollenin can be used for many different purposes in the food and pharmaceutical industries, including protection of probiotics in foods and delivery of live vaccines for pharmaceutical applications.