Trace level determination of organophosphorus pesticides in water with the new direct-electron ionization LC/MS interface.
A new LC/MS method for the determination of organophosphorus pesticides in water, based on the use of direct-electron ionization (EI) interface, is presented. Direct-EI is a new device that, in a very simple fashion, couples a nano-HPLC system with a mass spectrometer equipped with electron ionization capability. The nanoscale liquid flow allows for a direct introduction of eluate into the ion source and, after nebulization, for its ionization under typical EI conditions. Library-matchable EI spectra are generated for a choice of full scan or SIM detection of the analytes. In our case, a selection of organophosphorus pesticides, commonly distributed in local sugar beet cultivation, were considered. The new interface permits a very sensitive detection of the analytes in a wide range of linear response (0.09-9 ng). When applied to a real sample, the method allowed detecting four different pesticides at a concentration level of approximately 3 ng x L(-1).
Istituto di Scienze Chimiche F Bruner, Università di Urbino, Italy. achille@uniurb.it
Achille
A
Cappiello
Giorgio
G
Famiglini
Pierangela
P
Palma
Filippo
F
Mangani
D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004583:Electrons; D007306:Insecticides / Q000032:analysis*; D007477:Ions; D009946:Organothiophosphorus Compounds; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis*
D007306:Insecticides; D007477:Ions; D009946:Organothiophosphorus Compounds; D014874:Water Pollutants, Chemical