Pankow James F, Luo Wentai, McWhirter Kevin J, Sengupta Mohana, Strongin Robert M
Department of Civil and Environmental Engineering, PO 751, Portland, OR, 97207-0751, USA.
Department of Chemistry, Portland State University, Portland, OR, 97207, USA.
Sci Rep. 2025 May 23;15(1):17945. doi: 10.1038/s41598-025-01392-6.
S-6-methyl nicotine (S-6MN) has appeared as a nicotine substitute in commercial electronic e-cigarette products and pouches, including with the claim that such use is not regulated under current U.S. law. This work describes an analytical chemistry based search for the natural S/R presence of 6MN and three other MN compounds in additive-free cured leaf tobaccos and in multiple commercial tobacco products. The samples were extracted using 5 N NaOH, then methyl t-butyl ether. The extracts were analyzed using gas chromatography (GC) with mass spectrometric (MS) detection, and liquid chromatography (LC) with high resolution MS/MS detection. GC peaks with the correct retention times and MS patterns were found and confirmed for 6MN. Further confirmation for the presence of 6MN was obtained by LC/MS/MS. The all-sample average level of 6MN was determined to be 0.32 µg per g of tobacco material; the levels were too low to determine the S/R distributions. For 2MN, strong but not fully confirmed () evidence was obtained; analytical results are presented for 2MN at an all-sample average level of 0.10 µg per g of tobacco material. No evidence for either 4MN nor 5MN was found. Because most commercial nicotine is as extracted and purified from tobacco, 6MN can be expected in all such nicotine, and therefore in most nicotine-containing e-cigarettes (ENDS) as well as reagent-grade nicotine. Analyses of GC/MS data from past analyses of nine high-nicotine e-cigarette liquids purchased during the period 2018 to 2022 indicated a mean ± 1 s.d. result for 6MN of 6.3 ± 1.4 µg/mL.
S-6-甲基尼古丁（S-6MN）已作为尼古丁替代品出现在商业电子烟产品和烟弹中，甚至宣称这种使用在美国现行法律下不受监管。这项工作描述了一种基于分析化学的方法，用于寻找无添加剂的熟成烟叶以及多种商业烟草产品中6MN和其他三种MN化合物的天然S/R存在情况。样品先用5N氢氧化钠萃取，然后用甲基叔丁基醚萃取。萃取物采用气相色谱（GC）-质谱（MS）检测以及液相色谱（LC）-高分辨率MS/MS检测进行分析。发现并确认了具有正确保留时间和MS图谱的6MN的GC峰。通过LC/MS/MS进一步确认了6MN的存在。确定6MN在所有样品中的平均含量为每克烟草材料0.32微克；该含量过低，无法确定S/R分布。对于2MN，获得了有力但未完全确认（）的证据；给出了2MN在所有样品中的平均含量为每克烟草材料0.10微克的分析结果。未发现4MN和5MN的证据。由于大多数商业用尼古丁是从烟草中提取和纯化的，因此预计所有此类尼古丁中都含有6MN，进而大多数含尼古丁的电子烟（ENDS）以及试剂级尼古丁中也含有6MN。对2018年至2022年期间购买来的9种高尼古丁电子烟液过去分析的GC/MS数据进行分析，结果表明6MN的平均±1标准差为6.3±1.4微克/毫升。
