LIQUID-CHROMATOGRAPHY ATMOSPHERIC-PRESSURE IONIZATION MASS-SPECTROMETRY FOR THE DETERMINATION OF CHLOROPHENOLIC AND NITROPHENOLIC COMPOUNDSIN TAP WATER AND SEA-WATER

Liquid chromatography coupled to atmospheric-pressure ionization mass spectrometry (LC-API-MS) with negative ion detection was studied for t he determination of a variety of phenolic compounds in environmental w aters. An isocratic mobile phase of 0.05% acetic acid-acetonitrile (50 :50, v/v) was used. The influence of post-column addition of different bases on the sensitivity of the detection in electrospray (ES) was st udied. The [M-H](-) ion was the base peak for all the compounds using both ES and atmospheric-pressure chemical-ionization (APCI) ion source s. Moreover, abundant structural information was obtained by increasin g the extraction voltage. Detection limits for standard solutions rang ing from 2 to 13 ng injected for LC-ES-MS and from 0.02 to 20 ng for L C-APCI-MS were obtained. Good reproducibilities (day-to-day and run-to -run) were observed. The optimum LC-ES-MS and LC-APCI-MS conditions th us determined were used for a quantitative analysis of some phenolic c ompounds in spiked tap water and sea water samples. (C) 1997 Elsevier Science B.V.