On-line coupling of gel permeation chromatography with MALDI mass spectrometry

Gel permeation chromatography (GPC) was combined directly with aerosol matrix-assisted laser desorption/ionization (MALDI) mass spectrometry for the analysis of synthetic polymers. In the aerosol MALDI/GPC-MS experiment, effluent from the GPC column was combined with matrix solution and sprayed directly into a time-of-flight mass spectrometer (TOF-MS). Ions were formed by irradiation of the aerosol particles with pulsed 355 mn radiation from a frequency-tripled Nd:YAG laser. The ions were mass separated in a two-stage reflectron TOF-MS, and averaged mass spectra were stored every 11 s throughout the GPC-MS experiment. On-line GPC/ MALDI-MS was performed with the commercially available polymers poly(ethylene glycol) (PEG 1000) and poly(propylene glycol) (PPG 1000).