Accurate mass measurement of synthetic analogues of prazosine by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry

Matrix-assisted laser desorption/ionisation time-of-flight mass spectrometr y (MALDI-TOFMS) has been investigated as a tool for accurate determination of the molecular mass of synthetic analogues of prazosine, a molecule used for the treatment of hypertension. Samples were dissolved in methanol, mixe d with mass calibration standards, and crystallised on the target with alph a -cyano-4-hydroxycinnamic acid as matrix. Acquisition of spectra was rapid ly completed in reflectron mode, allowing high resolution (6000-10000) and sensitive (about 1-10 pmol of sample on target) determination of the synthe tic products. The results show the effectiveness of MALDI-TOFMS for accurat e mass determination of these fairly large molecules, which are otherwise d ifficult to analyse by other high-resolution mass spectrometric techniques. Copyright (C) 2001 John Wiley & Sons, Ltd.