This work presents a simple electrochemical method for Hg determination in fish oil capsules using anodic stripping voltammetry (ASV) on a screen‐printed gold electrode (SPGE). Samples were treated in an ultrasonic bath for 15 min in the presence of a 1 : 1 (v/v) concentrated HCl/H₂O₂ mixture at room temperature. The limit of detection (LOD) was estimated as 0.25 μg L⁻¹ (corresponding to 7.6 μg kg⁻¹ of oil) with a linear range between 5 and 400 μg L⁻¹ (90 s of deposition time). The analyzed fish oil samples presented Hg concentration below the LOD value. Recovery values for samples spiked with oil standard containing Hg ranged from 95 to 105 %. The method is precise (inter‐day and intra‐day RSD<4 % for n=3) as well as the SPGE sensors (RSD=4.3 %, n=3), which were used continuously (around 100 analyses without replacement) under such oxidation media. The proposed method is feasible to be applied for on‐site determinations due to the portability of sensing and sample treatment approaches.

中文翻译：

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使用丝网印刷金电极的溶出伏安法测定鱼油胶囊中的汞

这项工作提出了一种简单的电化学方法，用于在丝网印刷金电极（SPGE）上使用阳极溶出伏安法（ASV）测定鱼油胶囊中的Hg。在室温下，在1：1（v / v）浓HCl / H ₂ O ₂混合物的存在下，将样品在超声浴中处理15分钟。检出限（LOD）估计为0.25μgL ^-1（相当于7.6μgkg ^-1的油），线性范围为5至400μgL ^-1（沉积时间为90 s）。分析的鱼油样品中的汞浓度低于LOD值。加标了含汞油标准物的样品的回收率在95％至105％之间。该方法非常精确（n = 3时，日间和日内RSD <4％）以及SPGE传感器（RSD = 4.3％，n = 3），在以下条件下连续使用（约100次分析，无需更换）这样的氧化介质。由于传感和样品处理方法的便携性，该方法可用于现场测定。