Action spectroscopy of isomer-selected luciferin anions

Abstract

Abstract: Luciferin molecules are common luminophores found throughout the biological kingdoms. Here, electrospray ionization and tandem ion mobility spectrometry coupled with laser spectroscopy are used to demonstrate that D-luciferin and oxyluciferin deprotonated anions can be produced in two isomeric forms, which can be separated by virtue of their different collision cross sections with a buffer gas. The two isomers possess distinguishable but partially overlapping photodepletion action spectra over the visible range, implying distinct intrinsic absorption profiles. The site of deprotonation and tautomeric forms of the electrosprayed isomers are assigned through comparisons between exper..