Abstract：
On-line coupled high performance liquid chromatography-gas chromatography-flame ionisation detection (HPLC-GC-FID) was used to compare the effect of hydrogen, helium and nitrogen as carrier gases on the chromatographic characteristics for the quantification of mineral oil hydrocarbon (MOH) traces in food related matrices. After optimisation of chromatographic parameters nitrogen carrier gas exhibited characteristics equivalent to hydrogen and helium regarding requirements set by current guidelines and standardisation such as linear range, quantification limit and carry over. Though nitrogen expectedly led to greater peak widths, all required separations of standard compounds were sufficient and humps of saturated mineral oil hydrocarbons (MOSH) and aromatic mineral oil hydrocarbons (MOAH) were appropriate to enable quantitation similar to situations where hydrogen or helium had been used. Slightly increased peak widths of individual hump components did not affect shapes and widths of the MOSH and MOAH humps were not significantly affected by the use of nitrogen as carrier gas. Notably, nitrogen carrier gas led to less solvent peak tailing and smaller baseline offset. Overall, nitrogen may be regarded as viable alternative to hydrogen or helium and may even extend the range of quantifiable compounds to highly volatile hydrocarbon eluting directly after the solvent peak.
摘要：
在线耦合高效液相色谱-气相色谱-火焰电离检测（HPLC-GC-FID）用于比较氢气的影响，氦气和氮气作为载气对色谱特性的影响，用于定量食品相关基质中的矿物油烃（MOH）痕量。优化色谱参数后，氮气载气表现出与当前指南和标准化要求（如线性范围）相同的氢气和氦气特性，量化极限和结转。尽管氮预期会导致更大的峰宽，所有所需的标准化合物的分离都是足够的，并且饱和矿物油烃（MOSH）和芳香族矿物油烃（MOAH）的驼峰适合于能够进行类似于使用氢或氦的情况的定量。单个驼峰成分的峰宽略有增加，不会影响MOSH和MOAH驼峰的形状和宽度，也不会因使用氮气作为载气而受到显着影响。值得注意的是,氮气载气导致较少的溶剂峰拖尾和较小的基线偏移。总的来说,氮气可以被认为是氢气或氦气的可行替代品，甚至可以将可量化化合物的范围扩展到溶剂峰之后直接洗脱的高挥发性烃。
