Abstract

In this study, nickel ferrite nanoparticles highly dispersed in a carbonaceous matrix (C/NiFe₂O₄) demonstrated a high catalytic activity oxidizing 3,3′,5,5′-tetramethylbenzidine (TMB) without the use of hydrogen peroxide. The blue color of oxidized TMB decreases by the introduction of ascorbic acid (AA) in the reaction system, which allowed the development of a colorimetric analytical method for AA detection. To achieve the best analytical performance, the parameters such as pH, temperature, reaction time, TMB concentration, and amount of C/NiFe₂O₄, were optimized. Under optimal conditions, the variation in absorbance measured at 653 nm was found to be proportional in the concentration range of 1.0 to 25 μmol L⁻¹ with a detection limit of 0.26 μmol L⁻¹. C/NiFe₂O₄ was synthesized following a simple combustion method using egg white as a fuel and carbon source, and characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and vibrating sample magnetometry.

Graphic abstract

中文翻译：

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碳质基质上的镍铁氧体纳米颗粒及其比色法检测抗坏血酸

摘要

在这项研究中，高度分散在碳质基质（C / NiFe ₂ O ₄）中的镍铁氧体纳米粒子表现出高催化活性，可在不使用过氧化氢的情况下氧化3,3'，5,5'-四甲基联苯胺（TMB）。通过在反应体系中引入抗坏血酸（AA），氧化的TMB的蓝色减少，这使得开发用于检测AA的比色分析方法成为可能。为了获得最佳的分析性能，对诸如pH，温度，反应时间，TMB浓度和C / NiFe ₂ O _4的量等参数进行了优化。在最佳条件下，发现在653 nm处测得的吸光度变化在1.0至25μmolL ^-1的浓度范围内成比例检出限为0.26μmolL ^-1。通过使用蛋清作为燃料和碳源的简单燃烧方法合成C / NiFe ₂ O ₄，并通过X射线衍射，扫描电子显微镜，透射电子显微镜和振动样品磁强分析对其进行表征。

图形摘要