Artificial evolution of graphene oxide chemzyme with enantioselectivity and near-infrared photothermal effect for cascade biocatalysis reactions.

It is highly desirable and challenging when the chemzyme can be not only simply duplicating and imitating the properties of natural enzymes, but also introducing additional new features for practical applications. Herein, we report a zinc-finger-protein like α-helical chiral metallo-supramolecular complex ([Fe2L3](4+)) functionalized graphene oxide (GO-COOH) as a peroxidase mimic. This artificial enzyme integrates the characteristics of both chiral metallo-supramolecular complex and GO-COOH, and shows excellent catalytic activity. More intriguingly, the novel chemzyme turn out to have enantioselectivity and near-infrared photothermal effect. To the best of our knowledge, this is the first example that the chemzyme has such new features. Based on these properties, we have demonstrated three examples for the applications of our designed enzyme: 1) Intracellular H2O2 detection in PC12 cells against Alzheimer's disease; 2) Discrimination between the chiral drug, Levodopa (L-dopa), the gold standard for treating Parkinson's disease and its enantiomer, D-dopa. This is important because L-dopa is the most effective drug at present used to combat Parkinson's disease while D-dopa is inactive and can even cause side effects, thus for drug efficacy it must be free of D-dopa in the formulation; 3) Remote control of enzyme cascade biocatalysis reactions using high transparent, bio-friendly near-infrared (NIR) light. NIR allows remote activation with relatively high spatial and temporal precision. Our work will provide new insights into design and construction of novel chemzyme with more advanced features beyond intrinsic enzyme property.