Enzyme Mimetic Activity of ZnO-Pd Nanosheets Synthesized via a Green Route
Recent developments in the area of nanotechnology have focused on the development of nanomaterials with catalytic activities. The enzyme mimics, nanozymes, work efficiently in extreme pH and temperature conditions, and exhibit resistance to protease digestion, in contrast to enzymes. We developed an...
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MDPI AG
2020-06-01
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| Series: | Molecules |
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| Online Access: | https://www.mdpi.com/1420-3049/25/11/2585 |
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| author | Ravi Mani Tripathi Dohee Ahn Yeong Mok Kim Sang J. Chung |
| author_facet | Ravi Mani Tripathi Dohee Ahn Yeong Mok Kim Sang J. Chung |
| author_sort | Ravi Mani Tripathi |
| collection | DOAJ |
| description | Recent developments in the area of nanotechnology have focused on the development of nanomaterials with catalytic activities. The enzyme mimics, nanozymes, work efficiently in extreme pH and temperature conditions, and exhibit resistance to protease digestion, in contrast to enzymes. We developed an environment-friendly, cost-effective, and facile biological method for the synthesis of ZnO-Pd nanosheets. This is the first biosynthesis of ZnO-Pd nanosheets. The synthesized nanosheets were characterized by UV–visible spectroscopy, X-ray diffraction (XRD), scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray. The d-spacing (inter-atomic spacing) of the palladium nanoparticles in the ZnO sheets was found to be 0.22 nm, which corresponds to the (111) plane. The XRD pattern revealed that the 2θ values of 21.8°, 33.3°, 47.7°, and 56.2° corresponded with the crystal planes of (100), (002), (112), and (201), respectively. The nanosheets were validated to possess peroxidase mimetic activity, which oxidized the 3,3′,5,5′-tetramethylbenzidine (TMB) substrate in the presence of H<sub>2</sub>O<sub>2</sub>. After 20 min of incubation time, the colorless TMB substrate oxidized into a dark-blue-colored one and a strong peak was observed at 650 nm. The initial velocities of Pd-ZnO-catalyzed TMB oxidation by H<sub>2</sub>O<sub>2</sub> were analyzed by Michaelis–Menten and Lineweaver–Burk plots, resulting in 64 × 10<sup>−6</sup> M, 8.72 × 10<sup>−9</sup> Msec<sup>−1</sup>, and 8.72 × 10<sup>−4</sup> sec<sup>−1</sup> of <i>K</i><sub>M</sub>, <i>V</i><sub>max</sub>, and <i>k</i><sub>cat</sub>, respectively. |
| first_indexed | 2024-03-10T19:24:24Z |
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| language | English |
| last_indexed | 2024-03-10T19:24:24Z |
| publishDate | 2020-06-01 |
| publisher | MDPI AG |
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| series | Molecules |
| spelling | doaj.art-056c86e8fffe4935bdd6d782c022fbde2023-11-20T02:38:47ZengMDPI AGMolecules1420-30492020-06-012511258510.3390/molecules25112585Enzyme Mimetic Activity of ZnO-Pd Nanosheets Synthesized via a Green RouteRavi Mani Tripathi0Dohee Ahn1Yeong Mok Kim2Sang J. Chung3School of Pharmacy, Sungkyunkwan University, 2066 Seoburo, Jangan-gu, Suwon, Gyeonggido 16419, KoreaSchool of Pharmacy, Sungkyunkwan University, 2066 Seoburo, Jangan-gu, Suwon, Gyeonggido 16419, KoreaSchool of Pharmacy, Sungkyunkwan University, 2066 Seoburo, Jangan-gu, Suwon, Gyeonggido 16419, KoreaSchool of Pharmacy, Sungkyunkwan University, 2066 Seoburo, Jangan-gu, Suwon, Gyeonggido 16419, KoreaRecent developments in the area of nanotechnology have focused on the development of nanomaterials with catalytic activities. The enzyme mimics, nanozymes, work efficiently in extreme pH and temperature conditions, and exhibit resistance to protease digestion, in contrast to enzymes. We developed an environment-friendly, cost-effective, and facile biological method for the synthesis of ZnO-Pd nanosheets. This is the first biosynthesis of ZnO-Pd nanosheets. The synthesized nanosheets were characterized by UV–visible spectroscopy, X-ray diffraction (XRD), scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray. The d-spacing (inter-atomic spacing) of the palladium nanoparticles in the ZnO sheets was found to be 0.22 nm, which corresponds to the (111) plane. The XRD pattern revealed that the 2θ values of 21.8°, 33.3°, 47.7°, and 56.2° corresponded with the crystal planes of (100), (002), (112), and (201), respectively. The nanosheets were validated to possess peroxidase mimetic activity, which oxidized the 3,3′,5,5′-tetramethylbenzidine (TMB) substrate in the presence of H<sub>2</sub>O<sub>2</sub>. After 20 min of incubation time, the colorless TMB substrate oxidized into a dark-blue-colored one and a strong peak was observed at 650 nm. The initial velocities of Pd-ZnO-catalyzed TMB oxidation by H<sub>2</sub>O<sub>2</sub> were analyzed by Michaelis–Menten and Lineweaver–Burk plots, resulting in 64 × 10<sup>−6</sup> M, 8.72 × 10<sup>−9</sup> Msec<sup>−1</sup>, and 8.72 × 10<sup>−4</sup> sec<sup>−1</sup> of <i>K</i><sub>M</sub>, <i>V</i><sub>max</sub>, and <i>k</i><sub>cat</sub>, respectively.https://www.mdpi.com/1420-3049/25/11/2585green synthesis<i>Erigeron annuus</i> leaf extractZnO-Pd nanosheetsperoxidase mimetic activitynanozyme |
| spellingShingle | Ravi Mani Tripathi Dohee Ahn Yeong Mok Kim Sang J. Chung Enzyme Mimetic Activity of ZnO-Pd Nanosheets Synthesized via a Green Route Molecules green synthesis <i>Erigeron annuus</i> leaf extract ZnO-Pd nanosheets peroxidase mimetic activity nanozyme |
| title | Enzyme Mimetic Activity of ZnO-Pd Nanosheets Synthesized via a Green Route |
| title_full | Enzyme Mimetic Activity of ZnO-Pd Nanosheets Synthesized via a Green Route |
| title_fullStr | Enzyme Mimetic Activity of ZnO-Pd Nanosheets Synthesized via a Green Route |
| title_full_unstemmed | Enzyme Mimetic Activity of ZnO-Pd Nanosheets Synthesized via a Green Route |
| title_short | Enzyme Mimetic Activity of ZnO-Pd Nanosheets Synthesized via a Green Route |
| title_sort | enzyme mimetic activity of zno pd nanosheets synthesized via a green route |
| topic | green synthesis <i>Erigeron annuus</i> leaf extract ZnO-Pd nanosheets peroxidase mimetic activity nanozyme |
| url | https://www.mdpi.com/1420-3049/25/11/2585 |
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