Vihnanek Lazarus Maja, Sekovanić Ankica, Kljaković-Gašpić Zorana, Orct Tatjana, Jurasović Jasna, Kusak Josip, Reljić Slaven, Huber Duro
Arh Hig Rada Toksikol. 2013 Sep;64(3):395-403. doi: 10.2478/10004-1254-64-2013-2323.
A microwave-assisted digestion method for the determination of cadmium (Cd) and lead (Pb) by inductively coupled plasma mass spectrometry (ICP-MS) was optimised on certified reference material (CRM) (bovine liver, BCR-185R) and wolf liver samples. Different factors influencing digestion efficiency (temperature, time, composition of the digestion mixture, sample mass) were tested. Validation included linearity (up to 200 μg L(-1) for Cd and Pb), detection (0.003 μg L(-1) for Cd and 0.035 μg L(-1) for Pb), and quantification (0.008 μg L(-1) for Cd and 0.081 μg L(-1) for Pb) limits. Good agreement between measured and certified values was achieved in all conditions, with recoveries ranging from 94 % to 111 % for Cd and from 95 % to 105 % for Pb. The precision of the method, expressed as relative standard deviation, was up to 3 % for Cd and 8 % for Pb. The best digestion parameters (260 °C, 30 min, 1 mL HNO3+4 mL H2O, 0.1 g of CRM) based on accuracy and precision were applied on two wolf liver samples to evaluate the need for the predigestion step (freeze-drying) and appropriate mass of the sample. Freeze-drying improved precision and minimising the tissue mass to 0.1 g reduced the matrix effect. Using these optimised digestion conditions, we determined Cd and Pb in 40 wolf livers collected in Croatia, and their medians (0.055 μg g(-1) and 0.107 μg g(-1), respectively) were in the range of previously reported data for the grey wolf.
在认证参考物质（CRM）（牛肝，BCR - 185R）和狼肝样本上，对用于电感耦合等离子体质谱法（ICP - MS）测定镉（Cd）和铅（Pb）的微波辅助消解方法进行了优化。测试了影响消解效率的不同因素（温度、时间、消解混合物组成、样品质量）。验证包括线性（Cd和Pb高达200 μg L⁻¹）、检测限（Cd为0.003 μg L⁻¹，Pb为0.035 μg L⁻¹）和定量限（Cd为0.008 μg L⁻¹，Pb为0.081 μg L⁻¹）。在所有条件下，测量值与认证值之间均取得了良好的一致性，Cd的回收率在94%至111%之间，Pb的回收率在95%至105%之间。该方法的精密度以相对标准偏差表示，Cd高达3%，Pb高达8%。基于准确度和精密度，将最佳消解参数（260℃，30分钟，1 mL硝酸 + 4 mL水，0.1 g CRM）应用于两个狼肝样本，以评估预消解步骤（冷冻干燥）的必要性和合适的样品质量。冷冻干燥提高了精密度，将组织质量降至0.1 g可降低基质效应。使用这些优化的消解条件，我们测定了在克罗地亚收集的40个狼肝中的Cd和Pb，其中位数（分别为0.055 μg g⁻¹和0.107 μg g⁻¹）在先前报道的灰狼数据范围内。
