A new isotope dilution liquid chromatography/tandem mass spectrometric method was developed for the analysis of potential hydrazine present in tobacco smoke. The sample preparation was performed via an optimized derivatization method using an aqueous buffer:methanol solution of 2-nitrobenzaldehyde (10 g/L) used as a derivatizing agent. The mainstream smoke of cigarettes was passed through a glass fiber filter pad followed by a trapping solution containing an isotopically labeled 15N2-hydrazine used as internal standard. After smoking, the filter pad was extracted with the trapping solution and then incubated for 30 minutes at 35°C. An aliquot of the extract was centrifuged and the resultant hydrazone was quantified by liquid chromatography tandem mass spectrometry (LC-MS/MS). The isotope dilution standard calibration curve demonstrated good linearity (R2 > 0.999) from 0.079 to 248 ng/mL, with limits of quantification in mainstream smoke of 0.2 and 0.4 ng/cig for ISO and Canadian Intense smoking regimens, respectively. The method recovery was assessed using samples spiked with solutions of known amounts of hydrazine. The results showed good accuracy with recoveries ranging from 98 to 111%. Although there were no detectable levels of hydrazine in the reference cigarettes used in the validation (KR3R4F), the method precision was estimated to be ~10% based on the variability observed in the spiked samples. Trapping efficiencies were assessed using a hydrazine permeation tube providing a known amount of hydrazine vapor such that the distribution between the vapor phase and particulate phase of mainstream smoke could be determined.

中文翻译：

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用于分析烟草烟雾中肼的灵敏定量同位素稀释 LC-MS/MS 方法。


开发了一种新的同位素稀释液相色谱/串联质谱方法来分析烟草烟雾中潜在的肼。样品制备是通过优化的衍生化方法进行的，使用缓冲水溶液：2-硝基苯甲醛（10 g/L）的甲醇溶液作为衍生剂。香烟的主流烟雾通过玻璃纤维过滤垫，然后通过含有同位素标记的 15N2-肼作为内标的捕集溶液。吸烟后，用捕获溶液提取过滤垫，然后在 35°C 下孵育 30 分钟。将提取物的等分试样离心，并通过液相色谱串联质谱法 (LC-MS/MS) 对所得腙进行定量。同位素稀释标准校准曲线在 0.079 至 248 ng/mL 范围内表现出良好的线性 (R2 > 0.999)，ISO 和加拿大强烈吸烟方案主流烟雾的定量限值分别为 0.2 和 0.4 ng/cig。使用掺有已知量肼溶液的样品来评估方法回收率。结果显示出良好的准确性，回收率为 98% 至 111%。尽管验证中使用的参考香烟 (KR3R4F) 中没有检测到肼含量，但根据在加标样品中观察到的变异性，该方法的精确度估计约为 10%。使用提供已知量的肼蒸气的肼渗透管来评估捕集效率，从而可以确定主流烟雾的蒸气相和颗粒相之间的分布。