ABSTRACT
Two methods for determining 10 polycyclic aromatic compounds were developed. Both methods were based on high-performance liquid chromatography (HPLC), but one method used fluorescence detection, while the other used atmospheric pressure chemical ionization mass spectrometry (APCI-MS). For water analysis, solid-phase extraction (SPE) was on-line coupled to the separation system. Using a styrene-divinylbenzene copolymer (PLRP-s) as sorbent in the SPE and adding 20% of acetonitrile to the water sample before its preconcentration, recoveries were above 70% for most of the compounds. For the fluorescence method, all compounds were detected and six of them could be quantified at concentrations higher than 0.02 microg 1(-1). For the MS detection method, only seven of the compounds were detected and six were quantified at concentrations higher than 0.06 microg 1(-1). To analyse sediment samples, an extraction with dichloromethane was used and, due to the complexity of the matrix, a standard addition calibration was carried out. Seawater and sediment samples taken from the Tarragona fishing port and marina on the coast of Catalonia (Spain) were analysed, and five compounds (benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, benzo[ghi]perylene and indeno[1,2,3-cd]pyrene) were quantified in the sediment samples.
Subject(s)
Chromatography, High Pressure Liquid/methods , Geologic Sediments/chemistry , Heterocyclic Compounds/analysis , Mass Spectrometry/methods , Polycyclic Compounds/analysis , Seawater/chemistry , Sulfur Compounds/analysis , Atmospheric Pressure , Reference Standards , Sensitivity and Specificity , Spectrometry, FluorescenceABSTRACT
An automatic method for determining diuron, irgarol 1051, folpet and dichlofluanid in seawater samples have been developed. This method is based on the on-line coupling of solid-phase extraction (SPE) with a highly crosslinked polymeric sorbent, LiChrolut EN, to liquid chromatography followed by atmospheric pressure chemical ionization (APCI) and mass spectrometry. The operational parameters affecting the APCI interface have been studied in both positive and negative ionization modes. The use of LiChrolut EN in the SPE produced recoveries of over 85% for all the compounds when 100 ml of seawater sample was preconcentrated. Calibration was carried out in both ionization modes and in full-scan and selected-ion monitoring (SIM). The method allowed all the analytes to be detected at 5 ng l(-1) in SIM acquisition mode except folpet, which, because of its low response, could only be detected at 250 ng l(-1). The method was used to analyse water samples taken from five different marina and fishing ports along the coast of Tarragona, Catalonia (Spain), over a 5-month period. Diuron and irgarol 1051 were detected and quantified in most samples at concentration levels ranging from 27 to 420 ng l(-1) for diuron and from 15 to 511 ng l(-1) for irgarol 1051.
Subject(s)
Chromatography, Liquid/methods , Diuron/analysis , Mass Spectrometry/methods , Triazines/analysis , Water Pollutants, Chemical/analysis , Atmospheric Pressure , CalibrationABSTRACT
A fast analytical method for quantifying a mixture of 12 naphthalenesulfonates and naphthalenedisulfonates has been developed. This method consists of on-line ion-pair solid-phase extraction with PLRP-s sorbent and ion-pair liquid-chromatography using fast-scanning fluorescence spectrometer as a detection system and multivariate calibration. As complete separation is unnecessary, the compounds were analysed in isocratic conditions and the chromatographic analysis took only 25 min. Three-way partial least-squares (PLS) was used to carry out multivariate calibration for spiked tap water. In these conditions, quantification limits were between 0.01 and 3 microg x l(-1). Repeatability was also evaluated and relative standard deviations (n=3) were between 0.5 and 4, depending on the compound. Finally, spiked tap and Ebro river waters were analysed to evaluate prediction capability of the method.
