Abstract A facile electrochemical sensor for the individual and simultaneous quantification for elevated levels of dopamine, tryptophan, and serotonin was fabricated on pencil graphite electrode modified with 2, 3, 4, 6, 7, 8, 9, 10-octahydropyrimido[1, 2-a] azepine. The fabricated electrode was characterized by scanning electron microscopy and infrared spectroscopy. Voltammetric response of dopamine, tryptophan and serotonin on the electrode was attained by cyclic and differential pulse voltammetric techniques. Under experimental conditions, three well-separated irreversible oxidation peaks at +0.123 V, +0.302 V and +0.619 V were observed correspond to the oxidations of dopamine, serotonin and tryptophan. The anodic peak currents and the concentrations of dopamine, serotonin, and tryptophan were found to be linear in the range from 1 to 20 μM, 1–62 μM, and 1.5–750 μM with detection limits of 0.05, 0.27, and 0.05 μM, respectively. The linear ranges and the limits of detection for the simultaneous determination of these analytes are found to be superior to previously reported electrochemical sensors. The electropolymerization of 2, 3, 4, 6, 7, 8, 9, 10-octahydropyrimido[1, 2-a] azepine on a pencil graphite electrode is reported for the first time and the fabricated electrode is suitable for the determination of dopamine, serotonin and tryptophan in human blood and urine samples with good reproducibility and stability.

中文翻译：

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用电聚合 2, 3, 4, 6, 7, 8, 9, 10-八氢嘧啶 [1, 2-a] 氮杂环庚烷薄膜装饰的一次性铅笔石墨电极，用于同时伏安分析多巴胺、血清素和色氨酸

摘要 在用 2, 3, 4, 6, 7, 8, 9, 10-八氢嘧啶[1, 2]修饰的铅笔石墨电极上制造了一种简便的电化学传感器，用于单独和同时量化多巴胺、色氨酸和血清素水平升高。 -a] 氮杂。通过扫描电子显微镜和红外光谱对制备的电极进行表征。多巴胺、色氨酸和血清素在电极上的伏安响应是通过循环和差分脉冲伏安技术获得的。在实验条件下，在+0.123 V、+0.302 V 和+0.619 V 处观察到三个分离良好的不可逆氧化峰对应于多巴胺、血清素和色氨酸的氧化。发现阳极峰值电流和多巴胺、血清素和色氨酸的浓度在 1 到 20 μM 范围内呈线性关系，1–62 μM 和 1.5–750 μM，检测限分别为 0.05、0.27 和 0.05 μM。发现同时测定这些分析物的线性范围和检测限优于先前报道的电化学传感器。首次报道了2, 3, 4, 6, 7, 8, 9, 10-八氢嘧啶并[1, 2-a]氮杂在铅笔石墨电极上的电聚合反应，制备的电极适用于多巴胺的测定、血清素和色氨酸在人血和尿样中具有良好的重现性和稳定性。