IDENTIFICATION OF FRAGMENTATION IN MATRIX-ASSISTED LASER-DESORPTION MASS-SPECTROMETRY USING A VOLTAGE LABELING TECHNIQUE

A novel technique is presented for the study of post-source decay in m atrix-assisted laser desorption time-of-flight mass spectrometry, By i ntroducing a voltage labelling cell within the field-free region we ha ve been able to distinguish between intact ions, fragmented ions and n eutrals in a linear time-of-flight instrument, Results are presented f or positive and negative ions of bovine insulin (MW 5733) which demons trate the potential of the technique for investigating the effect of s ource conditions on post-source fragmentation. (C) 1997 by John Wiley & Sons, Ltd.