A non-enzymatic ascorbic acid sensor using a nickel ferrite/PANI (NF–PANI) nanocomposite and based on colorimetric and electrochemical sensing methods was investigated in this study. The nanocomposite was prepared by an in situ polymerization and utilized as an electrocatalyst to sense ascorbic acid (AA) through the peroxidase mimic sensing of H₂O₂ in the presence of 3,5,3,5-tetramethylbenzidine (TMB) as a coloring agent. It was also utilized to detect AA present in real samples prepared from fruit extracts, commercial beverages, and vitamin-C tablets. The limit of detection (LoD) for AA sensing by the peroxidase mimic method was found to be 232 nM. The relative standard deviation (RSD) calculated for analysis of the real samples analysis ranged from 1.7–3.2%. Similarly, the electrochemical sensing of AA by NF–PANI was examined by cyclic voltammetric, chronoamperometric, and differential pulse voltammetric analyses. The LoD for the electrochemical method applied to AA sensing was 423 nM. The nanocomposite functioned as an effective electrocatalytic sensing agent in both methods to selectively detect AA due to the combined effect of NF and PANI. Thus, it was shown that the nanocomposites could be utilized for the laboratory-based detection of AA by various methods and could give rapid results.

中文翻译：

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NiFe2O4-PANI 的纳米复合材料作为双活性电催化剂，用于抗坏血酸的灵敏比色和电化学传感

本研究研究了一种使用镍铁氧体/PANI (NF-PANI) 纳米复合材料并基于比色和电化学传感方法的非酶抗坏血酸传感器。该纳米复合材料通过原位聚合制备，并用作电催化剂，通过 H ₂ O _{2的过氧化物酶模拟感应来感应抗坏血酸 (AA)}在 3,5,3,5-四甲基联苯胺 (TMB) 作为着色剂存在下。它还用于检测从水果提取物、商业饮料和维生素 C 片剂制备的实际样品中存在的 AA。发现通过过氧化物酶模拟法检测 AA 的检测限 (LoD) 为 232 nM。为实际样品分析计算的相对标准偏差 (RSD) 范围为 1.7–3.2%。类似地，NF-PANI 对 AA 的电化学传感通过循环伏安法、计时电流法和差分脉冲伏安法分析进行了检验。应用于 AA 传感的电化学方法的 LoD 为 423 nM。由于 NF 和 PANI 的联合作用，纳米复合材料在两种方法中都可以作为有效的电催化传感剂来选择性地检测 AA。因此，