Separation and identification of various carotenoids by C-30 reversed-phase high-performance liquid chromatography coupled to UV and atmospheric pressure chemical ionization mass spectrometric detection

In this paper the application of on-line HPLC-UV-APCI (atmospheric pressure chemical ionization) mass spectrometry (MS) coupling for the separation an d determination of different carotenoids as well as cis/trans isomers of p- carotene is reported. All HPLC separations were carried out under RP condit ions on self-synthesized polymeric C-30 phases. The analysis of a carotenoi d mixture containing astaxanthin, canthaxanthin, zeaxanthin, echinenone and beta-carotene by HPLC-APCI-MS was achieved by scanning the mass range from mit 200 to 700. For the characterization of a sample containing cis/trans isomers of p-carotene as well as their oxidation products, a photodiode-arr ay W-visible absorbance detector was used in addition between the column an d the mass spectrometer for structural elucidation of the geometrical isome rs. The detection limit for p-carotene in positive-ion APCI-MS was determin ed to be I pmol. In addition, an extract of non-polar substances in vegetab le juice has been analyzed by HPLC-APCI-MS. The included carotenoids could be identified by their masses and their retention times. (C) 1999 Elsevier Science B.V. All rights reserved.