Tunable transition metal-ligand complexation for enhanced elucidation of flavonoid diglycosides by electrospray ionization mass spectrometry

摘要: A tunable ESI-MS/MS strategy for differentiation of flavone and flavanone diglycoside isomers based on metal complexation with auxiliary ligands is reported. The addition a salt an ligand to flavonoid solution results in the formation [M(II) (flavonoid-H) ligand]+ complexes, where M(II) transition metal. series electron-withdrawing substituents were synthesized tailor relative binding affinities thus directly influence stabilities, consequently dissociation pathways, complexes. Upon collisionally activated dissociation, complexes yield fragmentation patterns which abundances key diagnostic ions are enhanced, facilitating isomer differentiation.