Although peroxidase-like nanozymes have made great progress in bioanalysis,few current nanozymebased biosensors are constructed for discriminating isomers of organic compounds.Herein,fluorescent metal-organic framewor...Although peroxidase-like nanozymes have made great progress in bioanalysis,few current nanozymebased biosensors are constructed for discriminating isomers of organic compounds.Herein,fluorescent metal-organic framework(MOF)-based nanozyme is utilized for phenylenediamine isomers discrimination and detection.NH_(2)-MIL-101(Fe),as a member of Fe-based MOFs,functions as not only fluorescent indicator but also peroxidase mimics.In the presence of H_(2)O_(2),NH2-MIL-101(Fe) can catalyze the oxidation of o-phenylenediamine(OPD) and p-phenylenediamine(PPD) into their corresponding oxidation products(OPDox and PPDox),which in turn quench its intrinsic fluorescence at 445 nm via inner filter effect(IFE).Differently,a new fluorescence peak at 574 nm is observed for OPDox.Thus,a ratiometric fluorescence method for the detection of OPD can be designed with the fluorescence intensity ratio F_(574)/F_(445)as readout.This proposed strategy displays excellent discrimination ability for three phenylenediamines and may open new applications of MOFs in environmental science.展开更多
Dopamine(DA)is easy to be oxidized and polymerizes to form polydopamine(pDA)in alkaline conditions,while the synthesis is usually time-consuming(48 h).Herein,the polymerization of DA is completed with 4 h under the ca...Dopamine(DA)is easy to be oxidized and polymerizes to form polydopamine(pDA)in alkaline conditions,while the synthesis is usually time-consuming(48 h).Herein,the polymerization of DA is completed with 4 h under the catalysis of acid phosphatase(ACP).The high efficiency makes the detection of DA feasibility based on the self-polymerization of DA.In this assay,pDA is grown in situ on the surface of covalent organic frameworks(COFs),and then the fluorescence of COFs is quenched significantly.The linear range of DA is achieved from 0.5-50μmol/L with a detection limit of 0.16μmol/L.The detection of DA is not interfered with uric acid,ascorbic acid,and some phenolic compounds,because these substances cannot polymerize in the presence of ACP.Moreover,benefiting from the good sensitivity and selectivity,DA has been successfully determined by this strategy in human urine samples with satisfactory recoveries.展开更多
基金supported by the National Natural Science Foundation of China (No. 22076097)the Natural Science Foundation of Shandong Province (No. ZR2020MB066)。
文摘Although peroxidase-like nanozymes have made great progress in bioanalysis,few current nanozymebased biosensors are constructed for discriminating isomers of organic compounds.Herein,fluorescent metal-organic framework(MOF)-based nanozyme is utilized for phenylenediamine isomers discrimination and detection.NH_(2)-MIL-101(Fe),as a member of Fe-based MOFs,functions as not only fluorescent indicator but also peroxidase mimics.In the presence of H_(2)O_(2),NH2-MIL-101(Fe) can catalyze the oxidation of o-phenylenediamine(OPD) and p-phenylenediamine(PPD) into their corresponding oxidation products(OPDox and PPDox),which in turn quench its intrinsic fluorescence at 445 nm via inner filter effect(IFE).Differently,a new fluorescence peak at 574 nm is observed for OPDox.Thus,a ratiometric fluorescence method for the detection of OPD can be designed with the fluorescence intensity ratio F_(574)/F_(445)as readout.This proposed strategy displays excellent discrimination ability for three phenylenediamines and may open new applications of MOFs in environmental science.
基金supported by the Natural Science Foundation of Shandong Province,China(No.ZR2019QB010)National Natural Science Foundation of China(Nos.21705095,21775088)the Scientific Research Foundation of Qufu Normal University(No.BS D20130117).
文摘Dopamine(DA)is easy to be oxidized and polymerizes to form polydopamine(pDA)in alkaline conditions,while the synthesis is usually time-consuming(48 h).Herein,the polymerization of DA is completed with 4 h under the catalysis of acid phosphatase(ACP).The high efficiency makes the detection of DA feasibility based on the self-polymerization of DA.In this assay,pDA is grown in situ on the surface of covalent organic frameworks(COFs),and then the fluorescence of COFs is quenched significantly.The linear range of DA is achieved from 0.5-50μmol/L with a detection limit of 0.16μmol/L.The detection of DA is not interfered with uric acid,ascorbic acid,and some phenolic compounds,because these substances cannot polymerize in the presence of ACP.Moreover,benefiting from the good sensitivity and selectivity,DA has been successfully determined by this strategy in human urine samples with satisfactory recoveries.
