Although peroxidase-like nanozymes have made great progress in bioanalysis, few current nanozyme-based 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. NH2-MIL-101(Fe), as a member of Fe-based MOFs, functions as not only fluorescent indicator but also peroxidase mimics. In the presence of H2O2, 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 F574/F445 as readout. This proposed strategy displays excellent discrimination ability for three phenylenediamines and may open new applications of MOFs in environmental science.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |