Effect of polyethylene glycol additives on structure, stability, and biocatalytic activity of ormosil sol–gel encapsulated yeast cells

Biohybrid materials based on ormosil encapsulated yeast cells were synthesized through a one-step sol–gel route with base-catalyst (NaF) using tetraethoxysilane (TEOS), methyltriethoxysilane (MTES) and polyethylene glycol (PEG) with different molar weights as a structure-controlling agent. Phase contrast microscopy and scanning electron microscopy were employed to evidence possible structures of the materials. The addition of PEG during cell encapsulation has induced structural changes within the biohybrids, which depend on PEG molecular weights. The biocatalytic activity of the living hybrids has been investigated by a biosensor which was based on the Clark-type oxygen electrode. Graphical Abstract