Capillary tropane alkaloids

Mateus, L., Cherkaoui, S., Christen, P., and Veuthey, J. L. (1998). Capillary electrophoresis for the analysis of tropane alkaloids pharmaceutical and phytochemical applications. ]. Pharm. Biomed. Anal. 18, 815-825. 

Eeva, M., Salo, J. P., and Oksman-Caldentey, K. M. (1998). Determination of the main tropane alkaloids from transformed Hyoscyamus muticus plants by capillary zone electrophoresis. J. Pharm. Biomed. Anal. 16, 717—722. 

Current methods for tropane alkaloids analysis have been well covered in the literature. An excellent comprehensive review written by B. Drager [45] appeared in 2002, describing the analysis of tropane and related alkaloids in plant material. Sample preparation procedures were reviewed, as well as the analytical methods used for performing the separation and detection of tropane alkaloids, such as gas chromatography (GC), liquid chromatography (LC), and capillary electrophoresis (CE). Therefore, this chapter will not describe in detail these well-known analytical methods but discuss some recently developed applications for the analysis of tropane alkaloids in plant material and biological matrices. 

The isolation of atropine, scopolamine, and cocaine occurred long before the development of modern analytical techniques. Gas chromatography was the first instrumental technique available in the field of separation science and thus it is not surprising that these alkaloids were firstly analyzed by GC despite their low volatility. With the advent of capillary columns and the proliferation of various sample introduction and detection methods, GC has evolved as the dominant analytical technique for screening, identification, and quantitation of tropane alkaloids of plant origin as well as in biological fluids. The state-of-the-art of GC analysis of tropane alkaloids has been the subject of two comprehensive reviews [45,58]. We shall therefore mainly focus on publications which have appeared since 2002. 

L Mateus, S Cherkaoui, P Christen, JL Veuthey. Capillary electrophoresis-diode array detection-electrospray mass spectrometry for the analysis of selected tropane alkaloids in plant extracts. Electrophoresis 20 3402-3409, 1999. 

Ylinen M, Naaranlahti T, Lapinjoki S, Huhtikangas A, Salonen M-L, Simola LK, et al. Tropane alkaloids from Atropa belladonna. Part 1. Capillary gas chromatographic analysis. PlantaMed 1986 2 85 7. 

Tropane alkaloids from the Solanaceae have been frequently investigated by GC. The BSA (N,0-Bis(trimethylsilyl)acetamide) derivatives of scopolamine and 1-hyoscyamine have been quantified in extracts of suspension cultures and redifferentiated roots of Hyoscyamus niger (Yamada and Hashimoto 1982 Hashimoto and Yamada 1983) using a packed apolar column. More recently, the tropane alkaloid content of some species of this genus have been analyzed without derivatization with capillary apolar columns (Parr et al. 1990), using a method developed by Witte et al. (1987). 

GC-MS is the method of choice for identification of the components in complex mixtures of tropane alkaloids combining the high resolution power of capillary columns with the specificity of the mass detectors. It allows identification of tropane alkaloids without using of standard compounds. Isomers (at positions C3 and C6/7) are tentatively identified by Kovats retention indexes and cochromatography with reference compounds [16, 17]. In some cases, tentative identification of new tropane alkaloids has been possible by GC-MS [16, 24—26]. In fact, this is the only way to assess the minor or trace compounds, which are difficult or impossible to isolate. More than 30 0 tropane alkaloids can be detected in a single species by GC-MS [19]. GC-MS chromatogram of alkaloid extracts of D. stramonium L. hairy roots and representative MS spectra are presented in Fig. 7.1. 

In the recent years, capillary electrophoresis (CE) is widely used in alkaloid analysis because the nitrogen is easily charged. In the analysis of tropane alkaloids, it is applied for enantiomeric separation of atropine 5 and for analysis of pharmaceutical substances [22]. 

Various strategies have been applied during recent years to overcome the drawbacks associated with the analysis of tropane alkaloids by CE. Using atropine and scopolamine as model analytes, a comparison of UV and electrochemical detection (ED) in conjunction with non-aqueous CE (NACE) has been performed for capillaries with different internal diameters by Blasco et al. [108]. The results showed a significant increase in relative LODs with UV detection for capillaries... 

Ren X, Ma Y, Zhou M, Huo S, Yao J, Chen H (2008) Determination of tropane alkaloid components in Przewalskia tangutica Maxim, by capillary electrophraesis with electrochemiluminescence detection. Sepu 26 (Copyright (C) 2012 American Chemical Society (ACS). All Rights Reserved.) 223-227. doi 10.1016/sl872-2059(08)60015-2... 

Cherkaoui S, Varesio E, Christen P, Veuthey J-L (1998) Selectivity manipulation using nonaqueous capillary electrophoresis. Application to tropane alkaloids and amphetamine derivatives. Electrophoresis 19 2900-2906. doi 10.1002/elps.ll50191617... 

Humam M, Bieri S, Geiser L, Munoz O, Veuthey J-L, Christen P (2005) Separation of four isomeric tropane alkaloids from Schizantus grahamii by non-aqueous capillary electrophoresis. Phytochem Artal 16 349-356. doi 10.1002.pca.856... 

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