Zuccarello Pietro, Carnazza Giulia, Raffino Cataldo, Barbera Nunziata
Department "G.F. Ingrassia", Laboratory of Forensic Toxicology, University of Catania, Catania, Italy.
Legal Medicine Center of INAIL, Enna, Italy.
J Forensic Sci. 2022 Jul;67(4):1617-1623. doi: 10.1111/1556-4029.15046. Epub 2022 Apr 28.
Cyanide is a poison widely used in cases of suicide or homicide. Although various methods to identify and quantify this substance are reported in the literature, they are mainly validated on biological fluids (e.g., blood and urine). In the present study, the Anion-Exchange Liquid Chromatography with Pulsed Amperometric Detection (IC-PAD) method was validated on blood and, for the first time, on gastric content, and organs (brain, lung, and liver). For each matrix, linearity, accuracy, precision, limit of detection (LOD), lower limit of quantification (LLOQ), matrix interferences, and carryover were assessed. The samples were extracted by steam distillation in acid environment for the following analysis by IC-PAD. Furthermore, cyanide values found in two real poisoning cases are reported. For each investigated matrix, the analytical method satisfied all acceptance criteria for validation: it showed a good precision and accuracy, selectivity, and sensitivity with no carryover and matrix interference. The extraction by steam distillation in acid environment REDUCED the interference of the matrices and ALLOWED to perform the analysis with good precision and accuracy. In case #1, analysis showed a blood cyanide concentration of 0.99 μg/ml. In case #2, cyanide concentrations were 1.3 μg/g in brain, 0.8 μg/g in lung, 1.6 μg/g in liver, and 1.2 μg/g in gastric content. The cyanide concentrations found in the two reported cases have been suitable to cause death by poisoning.
氰化物是一种广泛用于自杀或他杀案件的毒药。尽管文献中报道了多种鉴定和定量该物质的方法，但它们主要在生物体液（如血液和尿液）上得到验证。在本研究中，阴离子交换液相色谱-脉冲安培检测法（IC-PAD）在血液上得到了验证，并且首次在胃内容物以及器官（脑、肺和肝）上得到了验证。对于每种基质，评估了线性、准确度、精密度、检测限（LOD）、定量下限（LLOQ）、基质干扰和残留。样品通过在酸性环境中进行水蒸气蒸馏提取，然后用IC-PAD进行分析。此外，还报告了两起实际中毒案件中发现的氰化物值。对于每种研究的基质，分析方法均满足验证的所有验收标准：它显示出良好的精密度和准确度、选择性和灵敏度，无残留和基质干扰。在酸性环境中通过水蒸气蒸馏提取减少了基质的干扰，使得能够以良好的精密度和准确度进行分析。在案例1中，分析显示血液中氰化物浓度为0.99μg/ml。在案例2中，脑内氰化物浓度为1.3μg/g，肺内为0.8μg/g，肝内为1.6μg/g，胃内容物中为1.2μg/g。在这两起报告的案件中发现的氰化物浓度足以导致中毒死亡。
