A quantitative and selective method for analysing indole alkaloids from complex mixtures was established by combining high‐performance liquid chromatography with mass spectrometry using a thermospray sample‐feeding principle. Detection limit was 100 pg per injection and response was linear up to 200 ng for all the compounds (catharanthine, tabersonine, serpentine and ajmalicine) that were to be analysed. The compounds were quite stable under conditions used, and the protonated molecular ions appeared as base peaks in the mass spectra and were selected for ion recording. An application of the assay for monitoring contents of the alkaloids in cell cultures derived from Catharanthus roseus is described in detail.
Auriola, S., Naaranlahti, T., Kostiainen, R., & Lapinjoki, S. (1990). Determination of Catharanthus alkaloids in plant cell cultures by thermospray liquid chromatography/mass spectrometry. Biomedical and Environmental Mass Spectrometry, 19(10), 609-612. https://doi.org/10.1002/bms.1200191006