摘要
Designing highly performed uricase-like nanozymes through enzymatic-like colorimetric analysis system is of vital significance for the quantitative detection of uric acid(UA).Herein,series of Ce-UiO-66 nanozymes with different surface charges through the ligand engineering strategy were rationally designed and synthesized as efficient uricase mimics with tailorable uricase-like activities to catalytically convert UA into allantoin and H2O2.Importantly,by tuning the functional groups of 1,4-benzoic acid ligands,we explored the relationships between the surface charges of Ce-UiO-66-X(X=H,NO_(2),Br,CH_(3),and OH)nanozymes and their uricase-like activity.Among them,Ce UiO-66-CH_(3) with the moderate surface charge exhibited optimal substrate adsorption and product desorption,displaying the highest uricase-like activity.Significantly,H2O2,as the product of UA oxidation,enabled Ce-UiO-66-CH_(3) itself as a dose-dependent chromogenic substrate of H_(2)O_(2),giving a white-to-orange color evolution due to the Ce-UiO-66-CH_(3)-to-CeO_(2) phase transition.Afterwards,a smartphone-assisted all-in-one enzyme/reagent-free biosensor based on Ce-UiO-66-CH_(3) was established for the precise visual detection of UA analysis,which was featured by a wide detection range(31–4000µM),a high sensitivity(limit of detection:8.9µM),a rapid response(-3 min),a high structural stability,and a high anti-interference ability.
基金
This work was supported by the National Key Research and Development Program of China(No.2021YFB3500904)
the National Natural Science Foundation of China(No.22475173)
the Key Research and Development Program of Shaanxi(No.2024SF-YBXM-439)
Authors also acknowledge the support from Fundamental Research Funds for the Central Universities(No.D5000210635).
