Fig. 9

Chromatographic and mass spectrometric results obtained for sample SCR3 (painting CAM-1328): a UV–Vis chromatogram extracted at 350 nm and UV–Vis absorption spectrum (insert) of the compound detected at 10.4 min and identified as PY3 (Hansa Yellow 10G—C.I. 11710); b extracted ion chromatogram obtained in positive ionization mode for m/z 395.031 corresponding to [M + H]⁺ of PY3 (molecular structure of the neutral molecule also reported); c corresponding tandem mass spectrum of [M + H]⁺ of PY3