Department of Chemistry and Environmental Science, New Jersey Institute of Technology, Newark, New Jersey 07102, United States.
Department of Process Research and Development, Merck Research Laboratories, Merck & Co., Inc., Rahway, New Jersey 07065, United States.
J Am Soc Mass Spectrom. 2022 May 4;33(5):875-884. doi: 10.1021/jasms.2c00064. Epub 2022 Apr 21.
Carcinogenic -nitrosamines were recently found in the sartan family of drugs and caused many drug recalls. Both of their detection and quantification are therefore important. Methods reported for -nitrosamine quantitation rely on the use of standards and are just applicable to simple -nitrosamines. There is an urgent need to quantify -nitrosamines derived from drugs with a complicated structure that lack standards. To tackle the issue, this study describes a novel absolute quantitation strategy for -nitrosamines using coulometric mass spectrometry (CMS) without standards. In our approach, -nitrosamine is first converted into electrochemically active hydrazine via zinc reduction under acidic condition and the resulting hydrazine can then be easily quantified using CMS. To validate our method, six simple -nitrosamines, -nitrosodiethylamine (NDEA), -nitroso-4-phenylpiperidine (NPhPIP), -nitrosodiphenylamine (NDPhA), -nitrosodibutylamine (NDBA), -nitrosodipropylamine (NDPA), and -nitrosopiperidine (NPIP), were chosen as test samples, and they all were quantified with excellent measurement accuracy (quantitation error ≤1.1%). Taking this one step further, as a demonstration of the method utility, a drug-like -nitrosamine, ()--(2-(6-chloro-5-methyl-1'-nitroso-2,3-dihydrospiro[indene-1,4'-piperidin]-3-yl)propan-2-yl)acetamide (), was also synthesized and successfully quantified using our method at 15 ppb level in a complex formulation matrix, following solvent extraction, -nitrosamine isolation, and reductive conversion. Because of the feature of requiring no standards, CMS provides a simple and powerful approach for -nitrosamine absolute quantitation and has great potential for analysis of other drug impurities or metabolites.
致癌亚硝胺最近在沙坦类药物中被发现，并导致了许多药物召回。因此，检测和定量它们都很重要。报告的用于定量亚硝胺的方法依赖于标准品的使用，并且仅适用于简单的亚硝胺。目前迫切需要对缺乏标准品的具有复杂结构的药物衍生的亚硝胺进行定量。为了解决这个问题，本研究描述了一种使用库仑质谱（CMS）无需标准品对亚硝胺进行绝对定量的新策略。在我们的方法中，首先在酸性条件下通过锌还原将亚硝胺转化为电化学活性的肼，然后可以使用 CMS 轻松定量生成的肼。为了验证我们的方法，选择了六种简单的亚硝胺，即二乙基亚硝胺（NDEA）、4-苯基哌啶亚硝胺（NPhPIP）、二苯基亚硝胺（NDPhA）、二正丁基亚硝胺（NDBA）、二正丙基亚硝胺（NDPA）和哌啶亚硝胺（NPIP）作为测试样品，它们的定量测量精度都非常好（定量误差≤1.1%）。更进一步，作为方法实用性的演示，我们还合成了一种类似药物的亚硝胺（）--（2-（6-氯-5-甲基-1'-亚硝基-2,3-二氢螺[茚-1,4'-哌啶]-3-基）丙-2-基）乙酰胺（），并成功地在复杂配方基质中以 15 ppb 的水平进行了定量，方法包括溶剂萃取、亚硝胺分离和还原转化。由于不需要标准品的特点，CMS 为亚硝胺的绝对定量提供了一种简单而强大的方法，并且在分析其他药物杂质或代谢物方面具有很大的潜力。
