Fig. 1From: HPLC-DAD and HPLC-ESI-Q-ToF characterisation of early 20th century lake and organic pigments from Lefranc archives a Base peak chromatogram obtained by HPLC-ESI-Q-ToF of the DMSO extract of sample P.8 (“No 8 Laque Geranium 2 B. 131. No 816 III April 1926”). Peaks labelled with an asterisk are also present in the analytical blank; b isotopic cluster relative to the peak assigned to phloxine B (Acid Red 92) in the chromatogram (negative ionization); c tandem mass spectrum (30 V) of the parent ion at m/z = 784.5, showing the mass fragments assigned to phloxine B. The structure of the pigment in its phenolic form is provided in the inset Back to article page