Puchalska, M., Orlinska, M., Ackacha, M.A., Połeć-Pawlak, K., & Jarosz, M. 2003 Identification of anthraquinone coloring matters in natural red dyes by electrospray mass spectrometry coupled to capillary electrophoresis.. Journal of Mass Spectrometry 38(12): 1252-1258.
Notes: [Conference title: 21st Informal Meeting on Mass Spectrometry held in Antwerp, Belgium, May 11-15, 2003] Capillary electrophoresis with UV/visible diode-array detection (DAD) and electrospray mass spectrometric (ESI-MS) detection were used for the identification of anthraquinone color components of cochineal, lac-dye and madder, natural red dyestuffs often used by ancient painters. For the purpose of such analysis, ESI-MS was found to be a much more appropriate detection technique than DAD one owing to its higher sensitivity (detection limits in the range 0.1-0.5 mug ml(-1)) and selectivity. The method developed made it possible to identify unequivocally carminic acid and laccaic acids A, B and E as coloring matters in the examined preparations of cochineal and lac-dye, respectively. In madder, European Rubia tinctorum, alizarin and purpurin were found. The method allows the rapid, direct and straightforward identification and quantification of components of natural products used in art and could be very helpful in restoration and conservation procedures.