The sodium lignosulfonate (SL) modified Fe₃O₄ (Fe₃O₄-SL) nanoparticles with excellent peroxidase-like activity were prepared by one-step solvothermal method, which were applied to sensing hydrogen peroxide (H₂O₂) and glutathione (GSH) with color change. Firstly, the morphology and composition of Fe₃O₄-SL nanoparticles were characterized. The results showed that the synthesized Fe₃O₄-SL nanoparticles had a spherical structure with an average diameter of 220 nm. Subsequently, the peroxidase-like activity of Fe₃O₄-SL nanoparticles was investigated by catalyzing the formation of blue-colored oxidized TMB (ox-TMB) by 3,3’,5,5’-tetramethylbenzidine (TMB) in the presence of H₂O₂. Mechanism studies showed that the Fe₃O₄-SL nanoparticles exhibited better catalytic activity than natural horseradish peroxidase (HRP), and the catalytic pathway abode by the ping-pong mechanism. Finally, the colorimetric sensor for H₂O₂ was established, which had a linear range of 0.5–150 μmol/L, a detection limit of 0.139 μmol/L and good selectivity. In addition, according to the decolorization reaction of ox-TMB and GSH and the scavenging effect of GSH on hydroxyl radicals, a colorimetric GSH sensor was further constructed. Based on the above results, a colorimetric detection platform for GSH was built, by which a detection range of 0.5–25 μmol/L and a detection limit of 0.08 μmol/L were obtained. The results above showed that the colorimetric sensing system constructed here had a wide detection range, good selectivity and stability for detection of GSH, which would provide an important reference in food monitoring, biomolecule detection and other fields.

采用一步溶剂热法制备了具有优异类过氧化物酶活性的木质素磺酸钠 (SL) 修饰的 Fe ₃ O ₄ (Fe ₃ O ₄ -SL) 纳米粒子，并将其应用于过氧化氢 (H ₂ O ₂ ) 和谷胱甘肽的传感(GSH) 有颜色变化。首先，表征了Fe ₃ O ₄ -SL纳米颗粒的形态和组成。结果表明，合成的Fe ₃ O ₄ -SL纳米颗粒具有球形结构，平均直径为220 nm。随后，Fe ₃ O ₄的过氧化物酶活性通过在 H ₂ O ₂存在下由 3,3',5,5'-四甲基联苯胺 (TMB) 催化蓝色氧化 TMB (ox-TMB) 的形成来研究 -SL 纳米粒子。机理研究表明，Fe ₃ O ₄ -SL 纳米粒子表现出比天然辣根过氧化物酶（HRP）更好的催化活性，并且催化途径属于乒乓机制。最后，H ₂ O ₂的比色传感器线性范围为0.5～150 μmol/L，检出限为0.139 μmol/L，选择性好。此外，根据ox-TMB与GSH的脱色反应以及GSH对羟基自由基的清除作用，进一步构建了比色GSH传感器。基于以上结果，搭建了GSH比色检测平台，检测范围为0.5～25 μmol/L，检出限为0.08 μmol/L。以上结果表明，所构建的比色传感系统对GSH的检测具有检测范围广、选择性和稳定性好等特点，可为食品监测、生物分子检测等领域提供重要参考。