Carbon dots confined in N-doped carbon as peroxidase-like nanozyme for detection of gastric cancer relevant D-amino acids

The concentrations of D-Proline (D-Pro) and D-Alanine (D-Ala) in the saliva of early-stage gastric cancer patients are prominently higher than those of healthy people. Therefore, precisely monitoring the concentrations of D-Pro and D-Ala has essential implications for gastric cancer diagnosis and treatment. Here, through pyrolysis of ZIF-8 precursor filled with glucose (G@ZIF-8), the carbon dots confined in N-doped carbon (CDs@NC) are successfully obtained. The CDs@NC can readily act as pemxidase-like nanozyme for the colorimetric detection of D-amino acids that associated with early gastric cancer. Intriguingly, the peroxidase-like activity of CDs@NC can be tuned easily by adjusting the content of glucose precursors. Further study of the catalytic mechanism shows that the superoxide radical (O-2(center dot-)) may be the critical Reactive oxygen species (ROS) involved in the peroxidase-like catalytic reactions. The excellent results of saliva tests suggest that the colorimetric method could be used to quickly distinguish patients with early gastric cancer from healthy people.

Automated summary

The study demonstrates the successful use of carbon dots confined in N-doped carbon (CDs@NC) as a peroxidase-like nanozyme for colorimetric detection of D-amino acids in saliva to distinguish early gastric cancer patients from healthy individuals. The peroxidase-like activity of CDs@NC can be easily adjusted by changing the content of glucose precursors, and superoxide radical (O-2(center dot-)) may play a critical role in the catalytic reactions.