Ce-Based MOF nanozyme with oxidase-like activity for sensitive colorimetric detection of glutathione in periodontitis

The detection of biomolecules using MOF-based nanozymes is a widely adopted strategy due to their abundant active sites and inherent enzymatic properties. In this study, we have synthesized three types of cerium metal-organic frameworks (Ce-MOFs) with oxidase (OXD)-like activity using a facile one-pot solvothermal method, simply by adjusting the concentrations of the raw ingredients, for the monitoring of biomolecules. The synthesized Ce-MOFs exhibit strong stability, a higher specific surface area, and more active sites, attributed to their MOF structure. These Ce-MOFs, with their excellent OXD-like activity, demonstrate satisfactory analytical performance in the quantitative determination of glutathione (GSH), showing a linear relationship within the range of 4.7 to 32.5   μM and detection limits as low as 42.76   nM. Furthermore, this colorimetric biosensor was successfully applied to monitor the content of GSH in the gingival crevicular fluid of patients with periodontitis. This paper extends the application of Ce-MOFs in bioassays and provides new insights into the application of OXD-like nanozymes in bioassays.