Abstract The voltammetric determination of quercetin in tea samples was performed at a modified sensor which was fabricated by the addition of a single-walled carbon nanotube dispersion on a glassy carbon electrode. Due to the electrochemcal activity of quercetin, electroanalytical methods were used with great success for the determination of quercetin. The electrochemical properties of quercetin were investigated. Quercetin in water and methanol extracts of tea samples were determined at the modified glassy carbon electrode by using square wave voltammetry. The results were found to be 116.4 and 116.3 µg quercetin equivalent/g dry green tea, 127.9 and 104.24 µg quercetin equivalent/g dry basil tea 27.5 and 26.1 µg quercetin equivalent/g dry black tea. The limit of detection and limit of quantification values for quercetin for the 0.01 to 100 µM concentration range were 7.7 nM and 25.6 nM, respectively. Very low concentrations of quercetin were successfully determined by square wave voltammetry with sensitivity and selectivity.

中文翻译：

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方波伏安法 (SWV) 在单壁碳纳米管 (SWCNT) 改性玻璃碳电极 (GCE) 上测定茶样品中的槲皮素

摘要 通过在玻碳电极上添加单壁碳纳米管分散体制成的改进型传感器对茶叶样品中的槲皮素进行伏安法测定。由于槲皮素的电化学活性，使用电分析方法测定槲皮素取得了巨大成功。研究了槲皮素的电化学性质。使用方波伏安法在改性玻碳电极上测定茶样品中水和甲醇提取物中的槲皮素。结果发现，116.4 和 116.3 µg 槲皮素当量/g 干绿茶，127.9 和 104.24 µg 槲皮素当量/g 干罗勒茶 27.5 和 26.1 µg 槲皮素当量/g 干红茶。槲皮素的检测限和定量限为 0。01 到 100 µM 的浓度范围分别为 7.7 nM 和 25.6 nM。通过具有灵敏度和选择性的方波伏安法成功测定了非常低浓度的槲皮素。