ONLINE 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 e xperiment, effluent from the GPC column was combined with matrix solut ion and sprayed directly into a time-of-flight mass spectrometer (TOF- MS). Ions were formed by irradiation of the aerosol particles with pul sed 355 mn radiation from a frequency-tripled Nd:YAG laser. The ions w ere mass separated in a two-stage reflectron TOF-MS, and averaged mass spectra were stored every 11 s throughout the GPC-MS experiment. On-l ine GPC/ MALDI-MS was performed with the commercially available polyme rs poly(ethylene glycol) (PEG 1000) and poly(propylene glycol) (PPG 10 00).