Novel strategy for ultrahigh density copper single atom enzymes developed for tumor therapies

A research group led by Prof. WANG Hui and Prof. ZHANG Xin from the Hefei Institutes of Physical Science of the Chinese Academy of Sciences introduced a new strategy to prepare ultrahigh density copper single atom enzymes for tumor self-cascade catalytic therapy.

"The powerful enzymes can help to fight tumors," said Dr. LIU Hongji, member of the research team.

The study was published in Chemical Engineering Journal .

The low-valence Cu single atom enzymes (Cu ^Ⅰ SAEs) contribute to alleviate inefficient generation of ·OH dilemma in tumor microenvironment, especially in the presence of overexpressed glutathione (GSH). However, the convenient controlled synthesis of Cu ^Ⅰ SAEs with high atom density remains to be a challenging task due to the cumbersome process, compositional heterogeneity, poor water solubility, and uncontrollable for the metal valence.

To solve this dilemma, the researchers proposed a well-controlled one-step solvent self-carbonization-reduction strategy to fabricate Cu ^Ⅰ SAEs with ultrahigh atomic density. Formamide can easily be condensed into a linear macromolecular chain for chelating Cu ^Ⅱ because of its high N content and vacant ligand sites. The resultant carbon nitride-based fragments reduce Cu ^Ⅱ to Cu ^Ⅰ .

"The obtained Cu ^Ⅰ SAEs has an incredibly high density of 23.36 wt. %, surpassing previously reported metal- or carbon-based supported Cu single-atom catalysts," explained LIU.

This comes from the well-defined Cu ^Ⅰ species, whereas aberration-corrected scanning transmission electron microscopy and the X-ray absorption fine structure spectroscopy corroborate the Cu ^Ⅰ species existed in the form of single atoms.

"The Cu ^Ⅰ SAEs showed remarkable self-cascade catalytic activities, leading to a tumor inhibition rate up to 89.17 %," he added.

This study provides a novel strategy for fabricating valence controlled SAEs supported on C ₃ N ₄ for catalytic applications, according to the team.

Chemical Engineering Journal

10.1016/j.cej.2023.148273

Ultrahigh density copper (Ⅰ) single atom enzymes for tumor self-cascade catalytic therapy

27-Dec-2023