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 ...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.展开更多
The variation in pollutant concentrations among different water bodies poses a significant challenge for environmental surveillance.Traditional UV-Vis spectrometers,with fixed optical paths,face limitations in accurat...The variation in pollutant concentrations among different water bodies poses a significant challenge for environmental surveillance.Traditional UV-Vis spectrometers,with fixed optical paths,face limitations in accurately determining Chemical Oxygen Demand(COD)and other water quality parameters.High concentrations surpass the detection limit,while low concentrations yield weak response signals,thereby compromising measurement accuracy.This study tackles these challenges by enhancing a UV-Vis spectrometer with a variable optical path.By utilizing a right-angle reflector for reflection and a stepping motor for control,measurements are conducted within the wavelength range of 190-700 nm.The instrument incorporates a spectral fusion algorithm to optimize spectral measurements within its operational range.Furthermore,a Partial Least Squares(PLS)model has been established for COD inversion by using laboratory standard solutions and field samples.The spectrometer has been tested in the nearshore waters of Shenzhen Bay,China,validating its applicability and the model’s accuracy.The utilization of a variable optical path UV-Vis spectrometer facilitates the acquisition of precise monitoring data with wide measuring range,thereby enabling the prompt detection of anomalies and subsequent reduction in reaction time.展开更多
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)+1 种基金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).
文摘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supported by the Bureau of Ecology and Environment of Shenzhen,Natural Science Foundation of Hunan Province(No.2023JJ50346)the Open Fund of National Engineering Research Center for Advanced Technology and Equipment of Water Environmental Pollution Monitoring(No.2024KFJJ0106).
文摘The variation in pollutant concentrations among different water bodies poses a significant challenge for environmental surveillance.Traditional UV-Vis spectrometers,with fixed optical paths,face limitations in accurately determining Chemical Oxygen Demand(COD)and other water quality parameters.High concentrations surpass the detection limit,while low concentrations yield weak response signals,thereby compromising measurement accuracy.This study tackles these challenges by enhancing a UV-Vis spectrometer with a variable optical path.By utilizing a right-angle reflector for reflection and a stepping motor for control,measurements are conducted within the wavelength range of 190-700 nm.The instrument incorporates a spectral fusion algorithm to optimize spectral measurements within its operational range.Furthermore,a Partial Least Squares(PLS)model has been established for COD inversion by using laboratory standard solutions and field samples.The spectrometer has been tested in the nearshore waters of Shenzhen Bay,China,validating its applicability and the model’s accuracy.The utilization of a variable optical path UV-Vis spectrometer facilitates the acquisition of precise monitoring data with wide measuring range,thereby enabling the prompt detection of anomalies and subsequent reduction in reaction time.
