Cascading H2O2 Self-Supplied System and Peroxygenases in a Triphasic Interface Nanobioreactor

Peroxygenase-catalyzed oxidation reactions rely on H2O2 as co-substrate. However, due to the poor robustness of peroxygenases toward H2O2, it is necessary to fabricate more efficient systems for stoichiometric in situ H2O2 production. Herein, a MoS2 nanosheet supported on the hydrophobic titanium dioxide (TiO2) film of a carbon paper (CP) (MoS2/TiO2/CP) surface was utilized to fix peroxygenase and construct a photocatalysis triphasic nanobioreactor. One side of the reactor was in contact with the analytical solution, while the opposing side was directly exposed to the gas phase. In particular, the generated electrons by photoinduction can reduce atmospheric O2 at the interface for H2O2 self-supply, and the levels of generated H2O2 could be regulated by the O2 concentration from the gas phase at the interface to further regulate peroxygenase catalytic activity. Compared with the conventional diphase interface, the catalytic efficiency of peroxygenase in the as-prepared reactor increased up to 35-fold. The product of benzene-containing substances catalyzed by triphasic nanobioreactors can be further proven by liquid chromatography/mass spectra (HPLC/MS). The above results indicated that the developed system has a potential application in biocatalysis and biosynthesis.