Chemistry Department, Ondokuz Mayis University, Samsun, Turkey.
J Sci Food Agric. 2021 Oct;101(13):5391-5397. doi: 10.1002/jsfa.11187. Epub 2021 Mar 12.
Teas and traditional herbs are taken as health remedies in most cultures worldwide. Plants often used in the manufacture of teas and herbal remedies can comprise carcinogenic contaminates, such as nitrates, nitrites and bromate ions. In the present study, a quick method was applied for the simultaneous determination of nitrate (NO ), nitrite (NO ) and bromate (BrO ) ions in some selected plants and tea samples using capillary electrophoresis and a Box-Behnken response surface design for method optimization.
Optimal conditions of 60 mmol L phosphate buffer solution at pH 3.5, a capillary temperature of 40 °C, applied voltage of -22.5 kV, total capillary length of 61.5 cm (effective length 53.5 cm) with capillary internal diameter of 50 μm, and an injection pressure of 50 mbar for 30 s were selected. The limits of detection for nitrate, bromate and nitrite were 0.49, 1.25 and 0.11 mg L , whereas linearity values were determined as 0.998, 0.996 and 0.999, respectively.
A quick and easy applicable method was developed and the detection of the anions was achievable within 6 min of analysis. From the studied samples (cherry stalk, a dry mixed herbal tea; cherry stalk, dry sticks; dry pomegranate flower; dry olive leaves; and black tea), dry pomegranate flower (13.10 ± 0.62 mg L ) and cherry stalk, dry mix herbal tea (13.10 ± 0.62 mg L ) had the highest nitrate content. © 2021 Society of Chemical Industry.
在世界上大多数文化中，茶和传统草药都被用作健康疗法。用于制造茶和草药疗法的植物通常可能含有致癌污染物，如硝酸盐、亚硝酸盐和溴酸盐离子。在本研究中，应用毛细管电泳和 Box-Behnken 响应面设计方法对一些选定的植物和茶样品中的硝酸盐（NO ）、亚硝酸盐（NO ）和溴酸盐（BrO ）离子进行了同时测定。
选择 60 mmol L 磷酸盐缓冲溶液在 pH 3.5、毛细管温度 40°C、施加电压-22.5 kV、总毛细管长度 61.5 cm（有效长度 53.5 cm）、毛细管内径 50 μm 和进样压力 50 mbar 下进行 30 s 的最优条件。硝酸盐、溴酸盐和亚硝酸盐的检出限分别为 0.49、1.25 和 0.11 mg L ，而线性度值分别为 0.998、0.996 和 0.999。
开发了一种快速简便的应用方法，在 6 分钟内可实现阴离子的检测。在所研究的样品（樱桃梗、干混合草药茶；樱桃梗、干棒；干石榴花；干橄榄叶；和红茶）中，干石榴花（13.10±0.62 mg L ）和樱桃梗、干混合草药茶（13.10±0.62 mg L ）的硝酸盐含量最高。© 2021 化学工业协会。
