Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry of phosphorylated compounds using a novel phosphate capture molecule

This paper introduces a simple, rapid, and sensitive procedure for the analysis of phosphorylated compounds (ROPO32-) by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS). The method is based on a characteristic mass shift and a total-charge change (from -2 to +1) of the phosphate residue due to complexation of ROPO32- with a dinuclear zinc(II) complex (1,3-bis[bis(2-pyridinylmethyl)amino]-2-propanolato dizinc(II) complex, Zn2L3+) in aqueous solution at physiological pH. Furthermore, the use of single zinc-isotope derivatives ((Zn2L3+)-Zn-64 and (ZnL3+)-Zn-68-L-2) enables improvement of the sensitivity and accuracy of the analysis. Copyright (C) 2003 John Wiley Sons, Ltd.