BEIJING -- Chinese scientists have introduced a metal-free nanozyme based on graphene quantum dots (GQDs) for highly efficient tumor therapy.

The study, conducted by a research group led by the Hefei Institutes of Physical Science of the Chinese Academy of Sciences, was published Thursday in the journal Matter.

According to the study, GQDs presents a promising and cost-effective means in tumor chemodynamic therapy (CDT). However, the limited catalytic activity of GQDs has posed great challenges for their clinical application, particularly under the challenging catalytic conditions.

To enhance the catalytic performance of the GQD-based nanocatalytic adjuvant, the researchers designed GQDs using a diatomic doping strategy.

According to the study, the GQDs have been shown to possess impressive peroxidase-mimicking activity. As a result, the GQDs are highly effective at inducing apoptosis and ferroptosis of cancer cells in vitro. They also selectively target tumors, with a tumor inhibition rate as high as 77.71 percent for intravenous injection and 93.22 percent for intratumoral injection, with no off-target side effects.

"The obtained GQDs, which are made from red blood cell membranes, are highly effective in treating tumors with few side effects," said Liu Hongji, a member of the research team.

"One of the advantages is that they are metal-free. In addition, they function as excellent peroxidase-like biocatalysts," Liu added.

This drug-free, target-specific, and biologically benign nanozyme has great potential as a potent biocatalyst for use in safe cancer treatment, according to the study.