本研究受到了美国药典现代化倡议和欧洲药品和医疗保健质量总局的推动。一次超规格（OOS）事件促使进行了关于聚乙二醇（PEG）中残留环氧乙烷的cGMP（指由FDA强制执行的《当前良好制造规范》）释放测试的OOS调查，该测试遵循《美国药典/国家处方集》（USP-NF）对聚乙二醇的标准以及欧洲药典（Ph.Eur.）对大分子聚醚的标准。在OOS根本原因调查中，我们观察到了PEG的降解物，并将其鉴定为甲酸甲酯，该物质与使用当前《美国药典/国家处方集》和欧洲药典中用于聚乙二醇的GC（气相色谱）方法共洗的环氧乙烷共洗。为了解决这个问题，我们开发了一种新的方法，利用静态顶空气相色谱-火焰离子化检测（HS-GC-FID），用于测试不同级别的聚乙二醇中残留的环氧乙烷、及其他与工艺相关的杂质和降解产物。使用这种新方法，已知的致遗传毒性杂质和IARC（国际癌症研究机构）1类人类致癌物环氧乙烷可以与新鉴定的相对无害的PEG降解物甲酸甲酯良好分离。当前的正式药典方法无法分离PEG中的特定杂质。然而，本文提出的新GC方法已被证明具有高度和独特的选择性，可以在PEG中实现所有相关杂质的基线分离（色谱分辨率大于1.5），这是一项具有挑战性的任务。此外，该方法也被发现是稳定性指示的，通过强制降解研究得出。在涉及酸、碱、热、光和氧化等PEG的应激稳定性研究中，我们还鉴定出了一些其他PEG降解物，包括甲醛。可能甲醛会发生被称为卡尼扎罗反应的不均化反应，导致甲酸和甲醇的生成。然后甲酸会与甲醇发生酯化反应生成甲酸甲酯。据我们所知，这是首个稳定性指示的HS-GC-FID方法，在一次运行中实现了这种分离，并且已根据ICH（国际药品技术要求协调组织）指南成功进行了验证。因此，该方法适用于在受监管的质量控制（QC）实验室进行cGMP批释放和稳定性测试的聚乙二醇。版权所有 © 2023 Elsevier B.V.。保留一切权利。

This work was motivated by the United States Pharmacopeia monograph modernization initiative and European directorate for the quality of medicines and healthcare. An out-of-specification (OOS) occurrence prompted OOS investigations for the cGMP (cGMP refers to the Current Good Manufacturing Practice regulations enforced by the FDA) release testing of residual ethylene oxide in polyethylene glycol (PEG) according to the standards detailed within the United States Pharmacopeia/National Formulary (USP-NF) for polyethylene glycol, and the European Pharmacopoeia (Ph. Eur.) for macrogols. During the OOS root cause investigations, we observed a PEG degradant and identified it as methyl formate, which co-elutes with ethylene oxide using the GC (gas chromatography) methods published in current USP-NF and Ph. Eur. for PEGs. To address this, a novel method utilizing static headspace gas chromatography with flame ionization detection (HS-GC-FID) was developed to test various grades of PEGs for the presence of residual ethylene oxide, along with other process related impurities and degradation products. With this new method, ethylene oxide, a known genotoxic impurity and IARC (International Agency for Research on Cancer) Class 1 human carcinogen, can be well resolved from methyl formate, a newly identified and comparatively innocuous degradant derived from PEG. The currently available official compendial methods are unable to separate the specific impurities in PEGs. However, the new GC method presented in this paper has been shown to have a high and unique selectivity, allowing for baseline separations (chromatographic resolutions greater than 1.5) of all related impurities in PEGs, which is a challenging task. Additionally, this method has been found to be stability-indicating based on a forced degradation study. During stress stability study of PEGs involving acid, alkali, heat, light, and oxidation, some other PEG degradants, including formaldehyde, were identified. It is possible that formaldehyde undergoes a disproportionation reaction known as the Cannizzaro reaction, leading to the formation of formic acid and methanol. The formic acid then undergoes an esterification reaction with methanol to produce methyl formate. To the best of our knowledge, this is the first stability-indicating HS-GC-FID method that accomplishes this separation in a single run, and it was successfully validated as per ICH (the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use) guidelines. Therefore, this method is suitable for the conduct of cGMP batch release and stability testing of PEGs in regulated quality control (QC) laboratories.Copyright © 2023 Elsevier B.V. All rights reserved.