MOF-derived Fe-doped $δ$-MnO$_2$ nanoflowers as oxidase mimics: Chromogenic sensing of Hg$^{2+}$ and hydroquinone in aqueous media
Fuente:
arXiv
Guardado en:
| Autores principales: | , , , , , |
|---|---|
| Formato: | Preprint |
| Publicado: |
2025
|
| Materias: | |
| Acceso en línea: | |
| Etiquetas: |
Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
|
| _version_ | 1866912777207021568 |
|---|---|
| author | Duhan, Udisha Pan, Arnab Dubey, Ritesh Layek, Samar Kumar, Sushil Goswami, Tapas |
| author_facet | Duhan, Udisha Pan, Arnab Dubey, Ritesh Layek, Samar Kumar, Sushil Goswami, Tapas |
| contents | Structure and morphology play a crucial role in enhancing the biomimetic oxidase activity of nanozymes. In this study, a facile \emph{in situ} chemical oxidation strategy was employed to synthesize MOF-derived MnO$_x$, utilizing the structural features of the parent MOF to enhance oxidase-mimicking activity. We systematically investigated the effects of phase evolution, structural modulation, and morphology on the oxidase activity of MnO$_x$ with Fe substitution. The oxidase-like activity was evaluated using the chromogenic substrate 3,3$'$,5,5$'$-tetramethylbenzidine (TMB), which produced a blue-colored oxidized TMB (ox-TMB) with an absorption peak at 652~nm upon oxidation. While all Fe-doped MnO$_x$ nanostructures exhibited oxidase-like activity, the 10\% Fe-doped sample (10Fe-MnO$_x$) demonstrated the highest performance, likely due to a synergistic effect of structure, morphology, and the presence of oxygen vacancies. The underlying oxidase mechanism was investigated using steady-state kinetics and electron paramagnetic resonance (EPR) analysis. In addition, a colorimetric assay was developed for the detection of Hg$^{2+}$ and hydroquinone (HQ) in real water samples collected from industrial and natural sources. The calculated detection limits of the 10Fe-MnO$_x$ colorimetric probe for HQ (1.74~$μ$M) and Hg$^{2+}$ (0.47~$μ$M) outperformed those of conventional metal oxide-based nanozymes. These findings pave the way for the development of easily synthesizable, scalable, and highly sensitive oxidase-based MOF-derived metal oxide nanomaterials with significant potential in biological and environmental applications. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2512_17731 |
| institution | arXiv |
| publishDate | 2025 |
| record_format | arxiv |
| spellingShingle | MOF-derived Fe-doped $δ$-MnO$_2$ nanoflowers as oxidase mimics: Chromogenic sensing of Hg$^{2+}$ and hydroquinone in aqueous media Duhan, Udisha Pan, Arnab Dubey, Ritesh Layek, Samar Kumar, Sushil Goswami, Tapas Mesoscale and Nanoscale Physics Materials Science Structure and morphology play a crucial role in enhancing the biomimetic oxidase activity of nanozymes. In this study, a facile \emph{in situ} chemical oxidation strategy was employed to synthesize MOF-derived MnO$_x$, utilizing the structural features of the parent MOF to enhance oxidase-mimicking activity. We systematically investigated the effects of phase evolution, structural modulation, and morphology on the oxidase activity of MnO$_x$ with Fe substitution. The oxidase-like activity was evaluated using the chromogenic substrate 3,3$'$,5,5$'$-tetramethylbenzidine (TMB), which produced a blue-colored oxidized TMB (ox-TMB) with an absorption peak at 652~nm upon oxidation. While all Fe-doped MnO$_x$ nanostructures exhibited oxidase-like activity, the 10\% Fe-doped sample (10Fe-MnO$_x$) demonstrated the highest performance, likely due to a synergistic effect of structure, morphology, and the presence of oxygen vacancies. The underlying oxidase mechanism was investigated using steady-state kinetics and electron paramagnetic resonance (EPR) analysis. In addition, a colorimetric assay was developed for the detection of Hg$^{2+}$ and hydroquinone (HQ) in real water samples collected from industrial and natural sources. The calculated detection limits of the 10Fe-MnO$_x$ colorimetric probe for HQ (1.74~$μ$M) and Hg$^{2+}$ (0.47~$μ$M) outperformed those of conventional metal oxide-based nanozymes. These findings pave the way for the development of easily synthesizable, scalable, and highly sensitive oxidase-based MOF-derived metal oxide nanomaterials with significant potential in biological and environmental applications. |
| title | MOF-derived Fe-doped $δ$-MnO$_2$ nanoflowers as oxidase mimics: Chromogenic sensing of Hg$^{2+}$ and hydroquinone in aqueous media |
| topic | Mesoscale and Nanoscale Physics Materials Science |
| url | https://arxiv.org/abs/2512.17731 |