A simple, low-cost, air-spray method for improved sample preparation for matrix-assisted laser desorption/ionisation mass spectrometry of derivatised poly(ethylene glycol) - Comment

A simple, low-cost, air-spray technique has been evaluated for the preparation of matrix-assisted laser desorption/ionisation (MALDI) sample slides. Hydroxyl end groups of poly(ethylene glycol) M-n = 600 were functionalised by esterification using acetyl and butyryl chlorides. Air-spray deposition gave excellent shot-to-shot and spot-to-spot reproducibility; the observed compositions by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) being in agreement with those obtained from H-1 NMR. Compressed air-spray is an excellent, inexpensive, sample preparation procedure for simple routine MALDI-TOF MS which increases the reproducibility of this increasingly important technique for synthetic polymer analysis.