Scholarlink

<p>Oxidative stress caused by excessive reactive oxygen species (ROS) is related to many diseases, and the importance of accurate detection of antioxidants is emphasized. Ascorbic acid (AA), a representative antioxidant, is widely used to assess total antioxidant capacity. Herein, we report the rational design of a bimetallic FeCo/N-C nanozyme via pyrolysis of a hemoglobin (Hb)-doped ZIF-67@ZIF-8 precursor. The Hb precursor plays a dual role: it acts as a molecular porogen to produce hierarchical porous structure, and as a coordination modulator to facilitate the formation of highly dispersed metal sites, thereby preventing cobalt aggregation and enhancing mass transfer. Crucially, the synthesized FeCo/N-C nanozyme exhibits exceptional oxidase-like activity by catalyzing the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) via a singlet oxygen (¹O<sub>2</sub>)-dominated non-radical pathway, as verified by electron paramagnetic resonance (EPR) spectroscopy. Based on AA’s reductive suppression of TMB oxidation, a sensitive and H<sub>2</sub>O<sub>2</sub>-free colorimetric sensing platform was developed for the quantification of AA. Under optimized conditions, the sensor displayed wide dual-linear ranges of 0.025–2.5 µM and 2.5–150 µM, a low detection limit of 0.006 µM, along with desired selectivity and stability. The method demonstrated practical applicability for AA quantification in body fluid samples, with satisfactory recoveries (98.14–104.36%) and good reproducibility (RSD &lt; 3.06%). This work provides a biomolecule-assisted strategy for the synthesis of high-efficiency nanozyme, and highlights the advantage of non-free radical catalysis mechanisms in constructing robust biosensor for clinical diagnosis and antioxidant analysis.</p> Graphical Abstract <p></p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Hemoglobin-assisted, ZIF-derived porous bimetallic FeCo/N-C nanozyme with high oxidase-like activity for colorimetric sensing

  • 期刊论文

  • 发表日期：

    2026年5月28日

查看全文
  • Zhenzhen Wang,
  • Yiyu Chen,
  • Xuexia Lin,
  • Huiting Lian,
  • Bin Liu,
  • Xiaofeng Wei

摘要

Oxidative stress caused by excessive reactive oxygen species (ROS) is related to many diseases, and the importance of accurate detection of antioxidants is emphasized. Ascorbic acid (AA), a representative antioxidant, is widely used to assess total antioxidant capacity. Herein, we report the rational design of a bimetallic FeCo/N-C nanozyme via pyrolysis of a hemoglobin (Hb)-doped ZIF-67@ZIF-8 precursor. The Hb precursor plays a dual role: it acts as a molecular porogen to produce hierarchical porous structure, and as a coordination modulator to facilitate the formation of highly dispersed metal sites, thereby preventing cobalt aggregation and enhancing mass transfer. Crucially, the synthesized FeCo/N-C nanozyme exhibits exceptional oxidase-like activity by catalyzing the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) via a singlet oxygen (¹O2)-dominated non-radical pathway, as verified by electron paramagnetic resonance (EPR) spectroscopy. Based on AA’s reductive suppression of TMB oxidation, a sensitive and H2O2-free colorimetric sensing platform was developed for the quantification of AA. Under optimized conditions, the sensor displayed wide dual-linear ranges of 0.025–2.5 µM and 2.5–150 µM, a low detection limit of 0.006 µM, along with desired selectivity and stability. The method demonstrated practical applicability for AA quantification in body fluid samples, with satisfactory recoveries (98.14–104.36%) and good reproducibility (RSD < 3.06%). This work provides a biomolecule-assisted strategy for the synthesis of high-efficiency nanozyme, and highlights the advantage of non-free radical catalysis mechanisms in constructing robust biosensor for clinical diagnosis and antioxidant analysis.

Graphical Abstract