Grupo Metabolômica, Universidade Estadual do Norte Fluminense, Laboratório de Ciências Quimicas, Av. Alberto Lamego, 2000, 28013-602, Campos dos Goytacazes, RJ, Brazil.
Grupo Metabolômica, Universidade Estadual do Norte Fluminense, Laboratório de Ciências Quimicas, Av. Alberto Lamego, 2000, 28013-602, Campos dos Goytacazes, RJ, Brazil.
Talanta. 2022 Jan 15;237:122928. doi: 10.1016/j.talanta.2021.122928. Epub 2021 Oct 8.
Adulteration of essential oils is a common and serious problem. Adequate and fast methods are required to establish the authenticity and purity. GC-MS, H and C NMR were compared in combination with similarity calculations as well as differential spectroscopy and chromatography for the authentication and determination of purity of vetiver essential oils. In the investigation of eight commercial oils H and C NMR adequately detected all six adulterants encountered in four of the commercial samples, while GC-MS was not able to detect adulteration with vegetable oils. A great advantage of the combined use of similarity calculation and NMR is that the authenticity can be verified without the need of concomitant measurement of a standard sample. The calculation can be carried out with a registered reference spectrum, in the case of H NMR acquired using the same magnetic field, but in the case of C NMR the spectrum can be obtained with another magnetic field. H NMR has the advantage of high speed, and the results can be obtained within minutes. C NMR was found to be superior in its ability to provide unequivocal identification of eventual adulterants, with differential spectroscopy revealing all signals of the adulterants.
精油掺假是一个普遍且严重的问题。需要足够快速的方法来确定其真实性和纯度。GC-MS、H 和 C NMR 结合相似性计算以及差示光谱和色谱法，用于鉴定和测定香根草精油的纯度。在对 8 种商业油的研究中，H 和 C NMR 充分检测到了在 4 种商业样品中遇到的所有 6 种掺杂物，而 GC-MS 则无法检测到植物油的掺假。相似性计算和 NMR 联合使用的一个巨大优势是，无需同时测量标准样品即可验证真实性。在使用相同磁场获得 H NMR 的情况下，可以使用注册的参考光谱进行计算，但在 C NMR 的情况下，可以使用另一个磁场获得光谱。H NMR 具有速度快的优点，结果可以在几分钟内获得。C NMR 具有能够提供最终掺杂物明确鉴定的优势，差示光谱揭示了所有掺杂物的信号。
