117828259

TLC-MS VERSUS TLC-LC-MS FINGERPRINTS OF HERBAL EXTRACTS. PART I. ESSENTIAL OILS

Mieczysław Sajewicz¹, Łukasz Wojtal¹, Maja Natić¹’², Dorota Staszek¹, Monika Waksmundzka-Hajnos³, and Teresa Kowalska¹*

¹ Institute of Chemistry, University of Silesia, 9 Szkolna Street, 40-006 Katowice, Poland ²Faculty of Chemistry, University of Belgrade, Studentski Trg 12-16, 11000 Belgrade, Serbia ³Deaprtment of Inorganic Chemistry, Medical University of Lublin, 6 Staszica Street, 20-081 Lublin, Poland

Abstract: In our earlier studies, we proposed the low-temperature thin-layer chromatography with densitometric and mass spectrometric detection (LT TLC-densitometry and LT TLC-MS, respectively) for fingerprinting of essential oils derived from several different species from the sagę (Salvia) genus (and morę generally, for fingerprinting of the complex mixtures of organie compounds of the natural, or synthetic origin). Development of the proposed LT-TLC-MS approach was only possible with use of the TLC-MS interface able to couple the developed chromatographic piąte with mass spectrometer. The goal of this study was to develop for the same purpose the two-dimensional liquid chromatographic system and to examine its performance with the sagę sample. Development of such a system was only possible with use of the TLC-MS interface and it included the low-temperature thin-layer chromatography coupled off-line with high-performance liquid chromatography, to build an overall LT TLC-LC-MS system. We compared the fingerprinting results for the essential oil of the test plant (Sahia lavandulifolia) obtained with use of the earlier proposed one-dimensional system (ID LT TLC-MS) and the results obtained with use of the two-dimensional system (2D LT TLC-LC-MS), newly proposed in this study. It was shown that the 2D approach to the separation of a complex mixture of botanical origin provides morę fingerprints for further investigations than the ID approach. Moreover, it is also elear that the 2D approach is better suited for identification of individual Chemical species contained in a given mixture, due to the simpler pattems of mass spectra obtained from the 2D analytical modę than from the ID one. However, with the constituents of the essential oil derived from Sahia lavandulifolia, a straightforward identification was not possible, basically due to