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1.
Anal Bioanal Chem ; 395(5): 1481-9, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19756534

ABSTRACT

Bag-SPE is a solid-phase extraction (SPE) technique here applied to sample pharmaceutical residues in wastewater. The device, consisting of 20 mg polystyrene-divinylbenzene (PS-DVB) enclosed in a woven polyester fabric was immersed into a 20-mL sample. Extraction of the analytes was performed under gentle rotation (25 rpm) until distribution equilibrium was achieved (4 h). The extraction efficiency for thirteen pharmaceuticals was evaluated for the bag-SPE sampler compared to a conventional SPE cartridge (Oasis HLB). All analyses were determined on an ultra-performance liquid chromatography (UPLC) coupled to a quadrupole time-of-flight (QToF) mass spectrometer. The detection limit of the bag-SPE technique for the analytes in wastewater ranged from 15-100 ng/L with recoveries between 20.7% and 58.2% and ion suppressions between 2.2% and 53.2%. Although the extraction efficiencies were lower with the bag-SPE sampler compared to the SPE technique, the two methods showed similar detection limits due to the lower ion suppression experienced with the bag-SPE. The results demonstrate that bag-SPE is an attractive alternative to the more, in terms of manual handling, demanding SPE technique.


Subject(s)
Sewage/chemistry , Solid Phase Extraction/methods , Water Pollutants, Chemical/analysis , Water Purification/methods , Water/chemistry , Chromatography, Liquid , Mass Spectrometry , Molecular Structure , Reproducibility of Results , Solid Phase Extraction/instrumentation
2.
Rapid Commun Mass Spectrom ; 15(24): 2438-45, 2001.
Article in English | MEDLINE | ID: mdl-11746915

ABSTRACT

Electrospray ionization tandem mass spectrometry (ESI-MS/MS) and ultraviolet diode array detection (UV-DAD), coupled on-line to reversed phase high performance liquid chromatography (HPLC), was used for the characterization of hydroxyalkyl derivatives of cob(I)alamin. The reduced form of vitamin B12, cob(I)alamin, denoted a supernucleophile due to its high nucleophilic strength, has shown promise as an analytical tool in studies of electrophilically reactive compounds in vitro and in vivo. A method for analysis of DNA-phosphate adducts was developed earlier utilizing the supernucleophilicity of cob(I)alamin to transfer alkyl groups from the phosphotriester configuration in DNA, with the formation of a Co-substituted alkyl-cobalamin (alkyl-Cbl) complex. For the purpose of identification and quantification of alkyl-Cbls at high sensitivity, an MS/MS method has been developed with application to a number of 2-hydroxyalkyl-cobalamins (OHalkyl-Cbls). The precursor oxiranes were reacted with cob(I)alamin, followed by clean-up and mass spectrometric analysis of the resulting OHalkyl-Cbls. It was found that ionization was highly dependent on solvent composition. By using acetonitrile/water/trifluoroacetic acid (TFA) (eluent I), the base peak was the doubly protonated molecule [M + 2H](2+), whereas acetonitrile/water/1-methylpiperidine (eluent II) yielded the singly protonated molecule [M + H](+) as the base peak. Excellent separation was obtained with eluent II, with good separation between stereoisomers, thus enabling the characterization of these by means of UV spectra. Limits of quantitation for 2-hydroxypropyl-cobalamin (OHPr-Cbl) were 0.2 and 2 pg/microL (or 0.1 and 1 fmol/microL) using selected ion recording (SIR) with eluent I and II, respectively. The obtained detection level should be sufficient for analysis of alkyl-Cbls from a wide range of toxicological applications.


Subject(s)
Vitamin B 12/analogs & derivatives , Vitamin B 12/analysis , Chromatography, High Pressure Liquid , Indicators and Reagents , Reference Standards , Spectrometry, Mass, Electrospray Ionization , Spectrophotometry, Ultraviolet
3.
Rapid Commun Mass Spectrom ; 14(4): 286-92, 2000.
Article in English | MEDLINE | ID: mdl-10669889

ABSTRACT

Isolated aquatic humic and fulvic acids were analysed with on-line size exclusion chromatography/electrospray ionisation mass spectrometry (SEC/ESI-MS). An eluent composition which enabled electrospray ionisation was identified. The SEC separation improved interpretability of mass spectra and may open up new possibilities for molecular weight determination of humic substances. A linear dose-response relationship over a factor of 20 was obtained and the limit of detection was 50ng/uL for humic and fulvic acids. Spectral changes due to different ionisation conditions (pH and cone voltage) were investigated. A natural water sample from a Swedish lake was analysed. Copyright 2000 John Wiley & Sons, Ltd.

4.
Talanta ; 46(3): 423-37, 1998 Jul.
Article in English | MEDLINE | ID: mdl-18967163

ABSTRACT

In an effort to develop common analytical methods for contaminated soil samples the Environmental Authorities of the Nordic countries have, together with Nordtest, published the report Nordic Guidelines for Chemical Analysis of Contaminated Soil Samples. The aim of these guidelines has been to describe analytical methods which could be accepted in all the Nordic countries and in that way contribute to reducing the variation in the analytical results between laboratories. The methods covered, reflects environmental concerns and priorities in the Nordic countries for now, i.e. heavy metals, chlorophenols, creosote, volatile organic compounds, PCB, THC and PAH. The repeatability and reproducibility of the guideline methods were determined in a Nordic inter-laboratory test in 1996, and the results showed some variations. The analytical methods and the results from the inter-laboratory tests are given for heavy metals, chlorophenols, creosote, volatile organic compounds and PCB.

5.
Environ Pollut ; 99(2): 177-98, 1998.
Article in English | MEDLINE | ID: mdl-15093312

ABSTRACT

The time trend monitoring of organochlorine pollution was carried out in Sweden since the late 1960s. This report presents data on concentrations of DDT, PCB, HCHs and HCB in biota samples collected and analysed annually. All the matrices and compounds studied show a significant decrease over time. The data cover severely polluted Swedish marine and fresh water in southern Sweden as well as locally unpolluted waters in remote northern Arctic regions of Sweden. A total of 13 time series representing different locations and species are presented for the different pollutants. The period studied covers the time when pollution was serious as well as the time of recovery. All monitoring activities were carried out at the same laboratories over the entire study period, which means that comparability over time is good in the sets of data presented. The various time trends show a convincing agreement with trends and annual change over time, although the concentrations differ between the species and locations investigated, the highest concentrations being in the south. Since the annual changes are normally similar regardless of locations and species, spatial variations in concentrations remain over time, although concentrations are lower today. The onset of changes in concentrations over time can be related to international measures or other circumstances that lowered releases into the environment. Similarities in the annual changes, as well as the time when changes began, are discussed with respect to suggested hypotheses on the fate of the investigated organochlorines. It was not possible to verify that the oxygenation of anoxic sediments mobilised old pollution in Baltic sediments. Neither was it possible to conclude that eutrophication has caused a measurable effect on the rate and timing of the decreases. Finally, long-range transport to Arctic regions seems to be due more to a one step transport than to the 'Grass-hopper' effect. The comprehensive database used, clearly shows how important it is to have datasets big enough to describe between-year variation before attempting to evaluate the time trend. In addition, if between-year variation is not known, it is then also difficult to evaluate spatial variation on the basis of single year observations.

6.
Environ Health Perspect ; 102 Suppl 4: 85-92, 1994 Oct.
Article in English | MEDLINE | ID: mdl-7529708

ABSTRACT

Extracts of gasoline and diesel vehicle exhaust and ambient air particles were fractionated into five fractions according to polarity on a silica gel column. Two medium polar fractions showing high genotoxic activity in the Ames test were further subfractionated, using normal-phase high-performance liquid chromatography. Chemical analyses were performed by means of gas chromatography combined with mass spectrometry and flame ionization and detection. The crude extracts, fractions, and subfractions were assayed with the Ames test, with and without S9, and the most abundant compounds in the subfractions are reported.


Subject(s)
Air Pollutants/analysis , Air Pollutants/toxicity , Mutagens/analysis , Vehicle Emissions/analysis , Vehicle Emissions/toxicity , Chemical Fractionation , Chromatography, Gas , Chromatography, High Pressure Liquid , Gasoline , Hydrocarbons/analysis , Hydrocarbons/toxicity , Mutagenicity Tests , Mutagens/toxicity , Salmonella typhimurium/drug effects
8.
Environ Health Perspect ; 47: 43-51, 1983 Jan.
Article in English | MEDLINE | ID: mdl-6186482

ABSTRACT

A cryogradient system for the enrichment of polycyclic aromatic hydrocarbons from gasoline and diesel powered vehicles is described. The sampling involves particle trapping on a filter followed by gas phase enrichment in three separate condensers. The filter is extracted with dichloromethane (DCM). For the extraction of the condensers three different solvents have been used; cyclohexane, acetone and DCM. The latter has also been used together with three buffers, pH 3, pH 7 and pH 11. Analyses of polynuclear aromatic hydrocarbons were performed by means of glass capillary gas chromatography and mass spectrometry. These analyses of diluted gasoline exhausts show that of the phenanthrene/anthracene, fluoranthene/pyrene and their monoalkylated forms found, between 90 and 30% are present in the gas phase. For diesel emissions, corresponding values are between 50% and 5%, respectively. However, the distribution of PAH between gas phase and particles is dependent on dilution ratio and filter temperatures. The addition of NO2 (approximately 7 ppm) prior to filter sampling involves degradation of cyclopenteno(cd)pyrene (CPedP) and benzo(a)pyrene (BaP) on the particles from diluted gasoline exhausts. This also occurs with BaP on diesel particles sampled under equivalent conditions. Mutagenicity data from these experiments support the theory of formation of direct-acting mutagens, probably due to nitration. Parallel sampling of particles with Teflon-coated and glass fiber filters does not show that components which are reactive to NO2, e.g., CPcdP, are degraded to a lower extent when glass fiber filters are used.


Subject(s)
Air Pollutants/analysis , Polycyclic Compounds/analysis , Vehicle Emissions/analysis , Equipment and Supplies , Methods
9.
Environ Health Perspect ; 47: 53-63, 1983 Jan.
Article in English | MEDLINE | ID: mdl-6186483

ABSTRACT

Different sampling methods for mutagenic polynuclear aromatic hydrocarbons (PAH) are described. These methods involve either direct sampling of raw exhausts which prior to filtering are cooled in a condenser, or filter sampling of exhausts diluted in a tunnel. The relevance of gas-phase PAHs of samples from diluted exhausts is discussed; methods used are either adsorbents (XAD-2) or cryogenic condensation. The emission of benzo(a)pyrene and certain other PAHs is reported from vehicles using different fuels (gasoline, diesel, LPG, alcohols) or different emission control systems. The emission of some volatiles, such as benzene, ethylene and alkylnitrites, is also presented from different types of fuels used.


Subject(s)
Polycyclic Compounds/analysis , Vehicle Emissions/analysis , Chromatography, Gas , Methods
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