School of Pharmacy, Faculty of Medical and Health Sciences, The University of Auckland, Auckland 1023, New Zealand.
National Institute for Health Innovation, The University of Auckland, Auckland 1010, New Zealand.
Int J Environ Res Public Health. 2018 Aug 13;15(8):1737. doi: 10.3390/ijerph15081737.
(1) Background: Despite the growing use of e-cigarettes, in most countries, there is no regulation covering manufacturing standards of the solution ('e-liquid'), leading to concerns over the accuracy of labelling and stability of the products under a range of conditions. Following the United States (US) Food and Drug Administration (FDA) requirements for manufacture of e-liquids, we aimed to develop a simple high-performance liquid chromatography (HPLC) method to determine nicotine content in nicotine-containing e-liquids, even in the presence of degradation products; (2) Methods: We developed an HPLC method to quantify nicotine in the presence of the two major constituents of all e-liquids, glycerine and propylene glycol, and in the presence of degradation products; (3) Results: Our HPLC method performed strongly and was validated it according to international guidelines. For the e-liquids tested, nicotine content levels were all higher than labelled (up to 117.9 ± 1.87% of the labelled content). While nicotine was shown to be unstable at 60 °C, it was stabilized at this temperature in the e-liquid formulations for up to 10 days; and (4) Conclusions: The HPLC method is suitable for adoption by laboratories to determine the actual content and stability of nicotine-containing products. The higher than labelled nicotine levels in e-liquids raises clinical and public health concerns.
(1) 背景：尽管电子烟的使用越来越多，但在大多数国家，都没有针对溶液（“电子烟液”）制造标准的规定，这引发了人们对产品标签准确性和在各种条件下产品稳定性的担忧。为了满足美国食品药品监督管理局（FDA）对电子烟液制造的要求，我们旨在开发一种简单的高效液相色谱（HPLC）方法，以确定含尼古丁的电子烟液中的尼古丁含量，即使在存在降解产物的情况下也是如此；(2) 方法：我们开发了一种 HPLC 方法来定量尼古丁，即使在存在所有电子烟液的两种主要成分甘油和丙二醇以及降解产物的情况下也是如此；(3) 结果：我们的 HPLC 方法性能良好，并根据国际指南进行了验证。对于测试的电子烟液，尼古丁含量均高于标签所示（高达标签含量的 117.9±1.87%）。虽然尼古丁在 60°C 下不稳定，但在电子烟液配方中，尼古丁在该温度下可稳定 10 天；(4) 结论：HPLC 方法适合实验室采用，以确定含尼古丁产品的实际含量和稳定性。电子烟液中尼古丁含量高于标签所示水平，引起了临床和公共卫生方面的关注。
