Liquid chromatography with triple-quadrupole and quadrupole-time-of-flight mass spectrometry for the determination of micro-constituents - a comparison.
The potential of liquid chromatography with triple-quadrupole mass spectrometry (LC-QqQ MS) was compared to that of quadrupole time-of-flight mass spectrometry (LC-Q-ToF MS) for the determination of microconstituents. Three applications were studied: (1) the ng/l quantification of five human drugs in surface water and waste-water effluents; (2) the quantification and confirmation of three corticosteroids in bovine urine at concentrations of 1-100 microg/l, and; (3) the confirmation of nicotine in rat plasma. In all cases, the criteria of the EU Commission Decision 2002/657/EC were followed (for confirmation analysis two MS/MS ions were monitored, and the ratio of their abundances were calculated and compared with those of standards). With both techniques fully satisfactory results were obtained in almost all instances. That is, unequivocal confirmation according to the most stringent EU criteria, those for "illegal compounds", was possible.One main advantage of LC-Q-ToF MS is that for identification and confirmation purposes, full MS/MS spectra are available after a single injection: no second injection, as required with QqQ MS, is needed. As well as the increased efficiency, the enhanced selectivity due to the impressive mass selectivity of LC-Q-ToF MS must be emphasized, which allows accurate masses of fragment ions to be calculated. Method characteristics such as linear dynamic range and repeatability were found to be essentially the same for both techniques, but LC-QqQ MS has the advantage that its detection limits are somewhat lower.
Stolker
Alida Linda A M
AL
Laboratory for Organic-analytical Chemistry, National Institute for Public Health and the Environment (RIVM), PO Box 1, 3720 BA, Bilthoven, The Netherlands. linda.stolker@rivm.nl
Niesing
Willem
W
Fuchs
Regine
R
Vreeken
Rob J
RJ
Niessen
Wilfried M A
WM
Brinkman
Udo A Th
UA
D000818:Animals; D002417:Cattle; D002853:Chromatography, Liquid / Q000379:methods*; D013058:Mass Spectrometry / Q000379:methods*; D004364:Pharmaceutical Preparations / Q000032:analysis / Q000097:blood / Q000652:urine; D051381:Rats; D014874:Water Pollutants, Chemical / Q000032:analysis
D004364:Pharmaceutical Preparations; D014874:Water Pollutants, Chemical