Fragmentation of chromophore labelled oligosaccharides induced by photodissociation with visible light

Abstract

Photodissociation with visible light (Vis-PD) has been applied to chromophore labelled oligosaccharide ions produced by electrospray in a Fourier-transform ion cyclotron resonance (FT-ICR) mass spectrometer. As chromophores four aromatic dyes, such as Rhodamine 110, have been attached to maltopentaose, lacto-N-fucopentaose I (LNFP I) and lacto-N-fucopentaose II (LNFP II). While in the positive ion mode the Vis-PD mass spectra show predominantly glycosidic cleavages and fragments from the reducing end of the carbohydrate, the negative ion spectra result in cross-ring cleavages and also glycosidic fragments mainly from the non-reducing end of the carbohydrate. It will be shown that Vis-PD mass spectrometry leads to sequence specific fragmentation.