biostudies-literatureZhang ZScience and Technology Planning Project of GuangzhouIndustry-University-Research Cooperation Project of Jiangsu ProvincePearl River Talent Program of Guangdong ProvinceNational Natural Science Foundation of ChinaScientific research foundation for high-level personnel in Jinling Institute of TechnologyGuangdong Basic and Applied Basic Research FundNatural Science Foundation of Jiangsu Province42163https://www.ebi.ac.uk/biostudies/studies/S-EPMC12658014biostudies-literatureUnknown15(1)Manganese oxide (MnO_x)-based nanozymes have attracted growing interest due to their low cost, high catalytic robustness, and adjustable oxidation states that influence enzyme-mimicking performance. In this study, we report a systematic approach to synthesize MnO_x nanocomposites with tunable Mn valence states via a two-step pyrolysis of Mn-BTC precursors, enabling us to explore their valence-dependent peroxidase-like activities. Among the synthesized forms, Mn₃O₄ exhibited the highest catalytic efficiency by facilitating the decomposition of H₂O₂ to generate hydroxyl radicals (•OH), which oxidize tetramethylbenzidine (TMB) to produce a blue-colored product. The catalytic mechanism was supported by UV-vis spectroscopy and fluorescence assays. KinetScientific reportsManganese oxide (MnO<sub>x</sub>) as peroxidase-mimicking nanozymes with valence-dependent activity for single-use colorimetric bioassays.PMC12658014223750922023A1515012820BK202418462024A04J63162021QN02X046BY2021300jit-b-201811Liu XZhang TShan HZheng HZhang ZAn JHui ZSun GDai HWang LfalseManganese oxide (MnO<sub>x</sub>) as peroxidase-mimicking nanozymes with valence-dependent activity for single-use colorimetric bioassays.Manganese oxide (MnO_x)-based nanozymes have attracted growing interest due to their low cost, high catalytic robustness, and adjustable oxidation states that influence enzyme-mimicking performance. In this study, we report a systematic approach to synthesize MnO_x nanocomposites with tunable Mn valence states via a two-step pyrolysis of Mn-BTC precursors, enabling us to explore their valence-dependent peroxidase-like activities. Among the synthesized forms, Mn₃O₄ exhibited the highest catalytic efficiency by facilitating the decomposition of H₂O₂ to generate hydroxyl radicals (•OH), which oxidize tetramethylbenzidine (TMB) to produce a blue-colored product. The catalytic mechanism was supported by UV-vis spectroscopy and fluorescence assays. Kinet2025-01-01T00:00:00Z2025 Nov2026-06-07T04:36:43.983Z2026-06-07T03:07:16.686ZS-EPMC126580144129857210.1038/s41598-025-26164-0