UV-Crosslinked Hydrogel Beads for Yeast Encapsulation and Fermentation Produced by Microfluidics

This study addresses some limitations of standard cell encapsulation methods by producing hydrogel beads via UV-induced C,H-insertion crosslinking (CHic) in a microfluidic setup and the simultaneous encapsulation of yeast cells. It describes a simple one-step production of monodisperse beads with consistent dimensions of ~1000 × 500 µm and the encapsulation of Saccharomyces cerevisiae within these beads. Glucose consumption profiles show that the encapsulated yeast consumes glucose at rates comparable to free yeast, indicating that encapsulation does not impair metabolic activity. The encapsulated cells maintain high retained metabolic activity for up to 15 days at 4 °C and even at 30 °C, whereas free yeast stored at this temperature suffers a significant loss of activity. This highlights the potential of the platform for storing cells without refrigeration. Another advantage is that the fermentation solutions remain clear with minimal turbidity, and the beads can be easily separated from the solution by simple sieving, thus avoiding the need to filter the solution after fermentation. The results obtained suggest that the platform is robust and versatile for use in fermentation bioreactors and cell storage.