Abstract Nano-scaled Fe3O4 were synthesized using solvothermal synthesis, and amino-modification of nano-scaled Fe3O4 was conducted with APTES. With Fe3O4-NH2 and Zn2+ as the metal centers, 2,6-pyridinedicarboxylic acids as the organic ligand, and using the one-step ultrasonic-assisted method, a new magnetic zinc pyridinedicarboxylic acid nanocomposite (Zn-(PDC)2@Fe3O4) was synthesized. The structure, composition and morphology of the products were characterized using methods such as X-ray single crystal diffraction, Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction, and scanning electron microscope. The results showed that the Zn-(PDC)2 was almost an octahedron, and the Zn-(PDC)2@Fe3O4 looked like a nanoflower. The mimetic peroxidase properties of Zn-(PDC)2@Fe3O4 were studied with H2O2 solution and TMB solution as the substrates, and the results showed that: the Michaelis constant of H2O2 by Zn-(PDC)2@Fe3O4 was: Km = 0.411 mM, the maximum reaction rate: vmax = 3.440 × 10−8 M s−1; the Michaelis constant of TMB by Zn-(PDC)2@Fe3O4 was: Km = 0.189 mM, and the maximum reaction rate: vmax = 2.419 × 10−8 M s−1, both of which were lower than those of H2O2 and TMB by Fe3O4 and Horseradish Peroxidase (HRP). Based on the reduction of the absorbance of original solution due to the consumption of H2O2 in oxidation-reduction reaction between SO32− and H2O2 under acid conditions, a new method for determining the content of SO32− was established. The linear range of SO32− was 8 × 10−7∼8 × 10−5 mol/L, the detection limit of SO32− was 8 × 10−8 mol/L, and the RSD of SO32− was 2.7–9.2%.

中文翻译：

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磁性吡啶二羧酸锌纳米复合材料(Zn-(PDC) 2 @Fe 3 O 4 )的制备及应用

摘要 采用溶剂热合成法合成了纳米级Fe3O4，并采用APTES对纳米级Fe3O4进行氨基修饰。以Fe3O4-NH2和Zn2+为金属中心，2,6-吡啶二羧酸为有机配体，采用一步超声辅助法制备新型磁性吡啶二羧酸锌纳米复合材料(Zn-(PDC)2@Fe3O4)被合成。采用X射线单晶衍射、傅里叶变换红外光谱(FTIR)、X射线粉末衍射、扫描电子显微镜等方法对产物的结构、组成和形貌进行表征。结果表明，Zn-(PDC)2 几乎是一个八面体，Zn-(PDC)2@Fe3O4 看起来像一个纳米花。以H2O2溶液和TMB溶液为底物研究了Zn-(PDC)2@Fe3O4的模拟过氧化物酶性质，结果表明：Zn-(PDC)2@Fe3O4对H2O2的米氏常数为：Km = 0.411 mM，最大反应速率：vmax = 3.440 × 10−8 M s−1；Zn-(PDC)2@Fe3O4对TMB的Michaelis常数为：Km = 0.189 mM，最大反应速率：vmax = 2.419 × 10−8 M s−1，均低于H2O2和TMB由 Fe3O4 和辣根过氧化物酶 (HRP) 组成。基于酸性条件下SO32-与H2O2的氧化还原反应消耗H2O2导致原溶液吸光度降低的问题，建立了测定SO32-含量的新方法。SO32-的线性范围为8×10-7∼8×10-5 mol/L，SO32-的检出限为8×10-8 mol/L，