Selective and sensitive detection of organic contaminants in water samples by on‐line trace enrichment–gas chromatography–mass spectrometry

Abstract

SummaryLiquid chromatographic (LC) type trace enrichment is coupled online with capillary gas chromatography (GC) with mass spectrometric (MS) detection for the analysis of aqueous samples. A volume of 1-10 ml of an aqueous sample is preconcentrated on a trace-enrichment column packed with a polymeric stationary phase. After cleanup with HPLC-grade water the precolumn is dried with nitrogen and subsequently desorbed with ethyl acetate. A fraction of 60 FI is introduced on-line into a diphenyltetramethyldisilazane-deactivated retention gap under partially concurrent solvent evaporation conditions and using an early solvent vapor exit. The analytes are separated and detected by means of GC-MS. The potential of the LC-GC-MS system for monitoring organic pollutants in river and drinking water is studied. Target analysis is carried out with atrazine and simazine as model compounds; the detection limits achieved under full-scan and multiple ion detection conditions are 30 pg and 5 pg, respectively. Identification of unknown compounds (non-target analysis), is demonstrated using a river water sample spiked with 168 pollutants varying in polarity and volatility.

Trace level analysis of micropollutants in aqueous samples using gas chromatography with on-line sample enrichment and large volume injection

“…Coupling MS detection to the SPE-GC system yields a hyphenated system that combines the automation potential of the SPE-GC system and the selectivity and sensitivity of MS detection [80,81]. The connection between the GC column and the ion source of the mass spectrometer was made via a 2 m x 150 Fm I.D.…”

“…9 illustrates the use of the system for the low ng/I level target analysis of atrazine and simazine in 1 ml river water samples using multiple ion detection [80,81]. The right hand side shows that 10 ml suffices to identify the analytes (at the same concentration level) under full scan acquisition conditions [81].…”

On-line reversed–phase liquid chromatography-gas chromatography coupled to mass spectrometry for enantiomeric analysis of chiral compounds in fruit beverages

“…With regard to the employment of mass spectrometry (MS) on-line coupled to a LC-GC system for food analysis, only a limited number of applications has been described by other researchers [18][19][20][21]. However, it is worth mentioning that up to date normal phase has been used in all cases as the employment of reversed phase in the LC-step not only makes it more difficult the solvent elimination during the LC-GC transfer but also the experimentation with MS.…”

On-line trace-level enrichment gas chromatography of triazine herbicides, organophosphorus pesticides, and organosulfur compounds from drinking and surface waters

“…21 Both are viable approaches, but the nitrogen purge has the advantage that it is easier to perform, and it has been applied in various real-life studies. [22][23][24][25] On the other hand, the possible loss of volatile analytes should not be overlooked.…”