Abstract A electrochemical sensor based on graphite and polycaprolactone (PCL), a biodegradable polymer, was developed for the first time. The electrodes were made in the proportions of 30–80% graphite-PCL w/w and characterized by thermogravimetric analysis (TGA), infrared spectroscopy, and cyclic voltammetry (CV). The composite of 70% graphite presented the best results, and it was also evaluated by Raman spectroscopy. The proposed electrode was successfully applied for the determinations of amlodipine (AML) or hydrochlorothiazide (HCTZ) in tablets and for the simultaneous determinations of AML and HCTZ in synthetic urine samples, using differential pulse voltammetry (DPV). The antihypertensive drugs showed oxidative peaks at 0.77 V for AML and at 0.98 V for HCTZ (vs. Ag|AgCl (3.0 mol L−1 KCl)). The simultaneous analytical curves were obtained in a Britton–Robinson buffer solution (pH 5.0) containing an anionic surfactant, sodium dodecyl sulfate (SDS) at a concentration of 2.0 × 10−4 mol L−1. The linearity ranges were 7.3 × 10−7 to 2.6 × 10−6 mol L−1 (n = 5, r = 0.998) and 2.4 × 10−6 to 2.2 × 10−5 mol L−1 (n = 5, r = 0.997) with detection limits of 6.8 × 10−8 and 2.7 × 10−7 mol L−1 for AML and HCTZ, respectively. Recoveries of these analytes in synthetic urine samples were 106.5% for AML and 103.2% for HCTZ.

中文翻译：

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基于石墨和聚己内酯的复合电极用于测定降压药的研制

摘要 首次开发了一种基于石墨和可生物降解聚合物聚己内酯（PCL）的电化学传感器。电极以 30-80% 石墨-PCL w/w 的比例制成，并通过热重分析 (TGA)、红外光谱和循环伏安法 (CV) 进行表征。70% 石墨的复合材料呈现出最好的结果，并且还通过拉曼光谱对其进行了评估。所提出的电极已成功应用于测定片剂中的氨氯地平 (AML) 或氢氯噻嗪 (HCTZ) 以及使用差分脉冲伏安法 (DPV) 同时测定合成尿样中的 AML 和 HCTZ。抗高血压药物在 AML 的 0.77 V 和 HCTZ 的 0.98 V 处显示氧化峰（相对于 Ag|AgCl (3.0 mol L-1 KCl)）。在含有阴离子表面活性剂十二烷基硫酸钠 (SDS) 的 Britton-Robinson 缓冲溶液 (pH 5.0) 中获得同步分析曲线，浓度为 2.0 × 10-4 mol L-1。线性范围为 7.3 × 10−7 到 2.6 × 10−6 mol L−1 (n = 5, r = 0.998) 和 2.4 × 10−6 到 2.2 × 10−5 mol L−1 (n = 5, r = 0.997)，AML 和 HCTZ 的检测限分别为 6.8 × 10−8 和 2.7 × 10−7 mol L−1。这些分析物在合成尿样中的回收率对于 AML 为 106.5%，对于 HCTZ 为 103.2%。AML 和 HCTZ 分别为 7 × 10−7 mol L−1。这些分析物在合成尿样中的回收率对于 AML 为 106.5%，对于 HCTZ 为 103.2%。AML 和 HCTZ 分别为 7 × 10−7 mol L−1。这些分析物在合成尿样中的回收率对于 AML 为 106.5%，对于 HCTZ 为 103.2%。