Abstract This paper proposed a graphite paste microelectrode (GPE) modified with 5,10,15,20-tetrakis(4-methoxyphenyl)-21H,23H-porphine cobalt (II) (CoTMPP) to enhance the electrocatalytic response towards the reduction of nicotinic acid (NA). A solution of Nafion polymer was used as a binder between the graphite powder and the electrocatalytic compound. The linear dynamic range of the microelectrode was wide (1.00 × 10−7–1.00 × 10−4 mol L−1) reaching a detection limit of 3.03 × 10−8 mol L−1. The proposed CoTMPP/Nafion/GPE was successfully applied for the determination of nicotinic acid in multivitamin syrup samples, with recovery rates between 94.2% and 103.3%. These results show the reliability of the proposed CoTMPP/Nafion/GPE for the determination of nicotinic acid in real samples.

中文翻译：

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5,10,15,20-四(4-甲氧基苯基)-21H,23H-卟啉钴(II)修饰的快速可再生石墨糊电极电化学测定烟酸

摘要 本文提出了一种用 5,10,15,20-四(4-甲氧基苯基)-21H,23H-卟啉钴 (II) (CoTMPP) 修饰的石墨糊微电极 (GPE)，以增强对还原烟碱的电催化响应。酸 (NA)。Nafion 聚合物溶液用作石墨粉和电催化化合物之间的粘合剂。微电极的线性动态范围很宽（1.00 × 10-7–1.00 × 10-4 mol L-1），检测限为3.03 × 10-8 mol L-1。所提出的 CoTMPP/Nafion/GPE 已成功应用于多种维生素糖浆样品中烟酸的测定，回收率在 94.2% 至 103.3% 之间。这些结果显示了所提出的 CoTMPP/Nafion/GPE 用于测定实际样品中烟酸的可靠性。