Photothermal enhanced enzymatic activity of lipase covalently immobilized on functionalized Ti3C2TX nanosheets

The rational design of new supports is critical for modern enzyme immobilization for advanced biocatalysis. Meanwhile, utilizing the photothermal effect of the support to achieve optical remote control of enzymatic activity remains a huge challenge. MXene, owing to its rich surface functional groups, biological compatibility and excellent photothermal effect, is a promising support material to satisfy the above requirements. Herein, a facile method to covalently bond lipase onto the surface of Ti3C2TX nanosheets through the coordination interaction with aminosilane ligand spacers is reported. The enzymatic activities of immobilized lipase are tuned based on the photothermal properties of Ti3C2TX nanosheets by exposure to near-infrared (NIR) light. The immobilized lipase shows an enhanced catalytic activity for the hydrolysis of p-nitrophenylpalmitate (pNPP) after NIR irradiation. In addition, immobilized lipase exhibits good pH, thermal stability and reusability, which are important in practical uses of enzymes.