The enlargement of the dietary supplement market has been observed in several countries around the world. However, the increasing consumption of these products raises concerns about their quality and safety. Considering the current scenario, the aim of this study was to develop a new method for screening of multiclass drugs as possible adulterants of dietary supplements. Six drug classes (stimulants, anorexics, anxiolytics, antidepressants, diuretics and laxatives) were studied by high performance liquid chromatography using a biphenyl stationary phase and a gold disc as the working electrode for pulsed amperometric detection (HPLC-PAD). A detection potential of +0.8 V proved to be more appropriate for the detection of all the drugs. A mobile phase consisting of 10 mmol L⁻¹ ammonium acetate in 64% (v/v) methanol at pH 4.0 (isocratic system), 1.0 mL min⁻¹ and 40 °C was used as the optimal conditions for chromatographic separations. Fenproporex, amfepramone, yohimbine, caffeine, sildenafil, tadalafil, furosemide, sertraline, fluoxetine, lorazepam, clonazepam, midazolam, diazepam and bisacodyl were separated after a 25 min chromatographic run. The limits of quantification ranged from 0.13 mg L⁻¹ (fenproporex) to 8.25 mg L⁻¹ (amfepramone), and accuracies from 86.24 to 114.82%. Ten samples of dietary supplements were analyzed, in which caffeine and yohimbine were determined among the studied drugs.

中文翻译：

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使用金电极和HPLC分离的脉冲安培法检测膳食补充剂中的药物掺杂物

膳食补充剂市场的扩大已在世界上多个国家中观察到。但是，这些产品的消耗量增加引起了对其质量和安全性的担忧。考虑到目前的情况，本研究的目的是开发一种新的方法，以筛选可能作为膳食补充剂掺假品的多类药物。通过高效液相色谱，使用联苯固定相和金碟作为脉冲安培检测（HPLC-PAD）的工作电极，对六种药物（兴奋剂，厌食药，抗焦虑药，抗抑郁药，利尿药和泻药）进行了研究。事实证明+0.8 V的检测电位更适合于所有药物的检测。由10 mmol L ^-1组成的流动相在pH 4.0（等度体系），1.0 mL min ^-1和40°C的64％（v / v）甲醇中的乙酸铵溶液用作色谱分离的最佳条件。在25分钟的色谱运行后，分离出Fenproporex，安非拉酮，育亨宾，咖啡因，西地那非，他达拉非，呋塞米，舍曲林，氟西汀，劳拉西m，氯硝西am，咪达唑仑，地西epa和比沙可啶。定量限为0.13 mg L ^-1（fenproporex）至8.25 mg L ^-1（氨苯乙酮），准确度为86.24至114.82％。分析了十种膳食补充剂样品，其中研究的药物中确定了咖啡因和育亨宾。