The offline combination of thin-layer chromatography and high-performance liquid chromatography with diode array detection and micrOTOF-Q mass spectrometry for the separation and identification of spinochromes from sea urchin (Strongylocentrotus droebachi

Thin-layer chromatography (TLC) with off-line high-performance liquid chromatography coupled to diode array detection and micrOTOF-Q mass spectrometry (HPLC–DAD–MS) resulted in the successful fractionation, separation and identification of spinochrome pigments from sea urchin (Strongylocentrotus droebachiensis) shells. Two fractions of pigments were separated by TLC and eluted with methanol using a TLC–MS interface. HPLC–DAD–MS analysis of the fractions indicated the presence of six sea urchin pigments: spinochrome monomers B and D, three spinochrome dimers (anhydroethylidene-6,6′-bis(2,3,7-trihydroxynaphthazarin) and its isomer and ethylidene-6,6′-bis(2,3,7-trihydroxynaphthazarin)), and one pigment that was preliminary identified as a spinochrome dimer with the structural formula C22H16O16.