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1.
Environmental endocrine disruptors such as estrone (E1) and beta-estradiol (E2) are excreted in human urine primarily as water-soluble glucuronides and sulfates that can dissociate in wastewater treatment systems to the more active free estrogens. Measurement of the distribution and fate of the steroid conjugates and the corresponding free estrogens in treatment plants and receiving waters is critical for understanding the reproductive and developmental effects of these substances on aquatic organisms. A sensitive method to measure steroid estrogen conjugates in matrix-rich sewage influents and effluents (method detection limits ranged from 0.04 to 0.28 ng/L) has been developed using HPLC tandem mass spectrometry with electrospray ionization. The method employs extensive sample purification by selective extraction from an Oasis HLB solid-phase cartridge followed by separation by anion exchange chromatography. This purification scheme, combined with a stable isotope dilution approach, was used to overcome problems of matrix suppression of ionization and permitted selective and sensitive detection of six target conjugates of E1 and E2. Accurate quantitation was highly dependent on the method of sample preservation. Acidification of each sample (pH 2.0) was effective in preventing enzymatic or chemical decomposition of steroid conjugates in all sample types, whereas glucuronide conjugates were hydrolyzed in the presence of mercury and formalin preservatives. Measured concentrations of steroid sulfates in the influent to a sewage treatment plant were approximately 100 times greater than that of the respective steroid glucuronides, suggesting that the preponderance of glucuronides had dissociated prior to reaching the treatment plant. A small percentage of the steroid sulfates persisted through biological treatment of sewage and was measured in the effluent. Steroid conjugates that survive decomposition or bypass biological treatment of municipal wastewater are released into surface waters and may serve as a source of free steroids.  相似文献   

2.
An analytical method has been developed and validated for the simultaneous trace determination of four macrolide antibiotics, six sulfonamides, the human metabolite N4-acetylsulfamethoxazole, and trimethoprim in wastewater. The method was validated for tertiary, secondary, and-unlike in previously published methods-also for primary effluents of municipal wastewater treatment plants. This wide range of application is necessary to thoroughly investigate the occurrence and fate of chemicals in wastewater treatment. Wastewater samples were enriched by solid-phase extraction, followed by reversed-phase liquid chromatography coupled to tandem mass spectrometry using positive electrospray ionization. Recoveries from all sample matrixes were generally above 80%, and the combined measurement uncertainty varied between 2 and 18%. Concentrations measured in tertiary effluents ranged between 10 ng/L for roxithromycin and 423 ng/L for sulfamethoxazole. Corresponding levels in primary effluents varied from 22 to 1450 ng/L, respectively. Trace amounts of these emerging contaminants reach ambient waters, since all analytes were not fully eliminated during conventional activated sludge treatment followed by sand filtration. In the case of sulfamethoxazole, the amount present as human metabolite N4-acetylsulfamethoxazole had to be taken into account in order to correctly assess the fate of sulfamethoxazole in wastewater treatment.  相似文献   

3.
A new, rapid method for selective extraction of hydroxylated polycyclic aromatic hydrocarbons metabolites (OH-PAHs) in human urine was developed using an immunosorbent of anti-pyrene antibodies which were encapsulated in a sol-gel glass (SGG) matrix. Resulting chromatograms after immunoextraction of urine samples and HPLC analysis of the extracts were free from matrix interferences. The LODs for the determination of OH-PAHs in these difficult samples were in the low-ppt range (1-16 ng/L). In addition to its high selectivity, the immunosorbent proved to be robust and reusable. Obtained recoveries in spiked urine samples ranged from 83 to 107% for the hydroxyphenanthrene and hydroxypyrene compounds under investigation, while recovery for 3-hydroxybenzo[a]pyrene was only 45-62%. In a biomonitoring study, the SGG immunosorbent was successfully used for trace-level analysis of OH-PAHs in 20 human urine samples. Results were compared to data obtained by an independent reference analysis method and revealed good correlation between both methods.  相似文献   

4.
Treated wastewater effluent is a potential environmental point source for antidepressant pharmaceuticals. A quantitative method was developed for the determination of trace levels of antidepressants in environmental aquatic matrixes using solid-phase extraction coupled with liquid chromatography-electrospray ionization tandem mass spectrometry. Recoveries of parent antidepressants from matrix spiking experiments for the individual antidepressants ranged from 72 to 118% at low concentrations (0.5 ng/L) and 70 to 118% at high concentrations (100 ng/L) for the solid-phase extraction method. Method detection limits for the individual antidepressant compounds ranged from 0.19 to 0.45 ng/L. The method was applied to wastewater effluent and samples collected from a wastewater-dominated stream. Venlafaxine was the predominant antidepressant observed in wastewater and river water samples. Individual antidepressant concentrations found in the wastewater effluent ranged from 3 (duloxetine) to 2190 ng/L (venlafaxine), whereas individual concentrations in the waste-dominated stream ranged from 0.72 (norfluoxetine) to 1310 ng/L (venlafaxine).  相似文献   

5.
A multirun analytical method has been developed and validated for trace determination of 24 antibiotics including 7 sulfonamides, 3 macrolides, 7 quinolones, 6 tetracyclines, and trimethoprim in chlorine-disinfected drinking water using a single solid-phase extraction method coupled to liquid chromatography with positive electrospray tandem mass spectrometry detection. The analytes were extracted by a hydrophilic-lipophilic balanced resin and eluted with acidified methanol (0.1% formic acid), resulting in analyte recoveries generally above 90%. The limits of quantitation were mostly below 10 ng/L in drinking water. Since the concentrated sample matrix typically caused ion suppression during electrospray ionization, the method of standard addition was used for quantitation. Chlorine residuals in drinking water can react with some antibiotics, but ascorbic acid was found to be an effective chlorine quenching agent without affecting the analysis and stability of the antibiotics in water. A preliminary occurrence study using this method revealed the presence of some antibiotics in drinking waters, including sulfamethoxazole (3.0-3.4 ng/L), macrolides (1.4-4.9 ng/L), and quinolones (1.2-4.0 ng/L).  相似文献   

6.
A new method was developed for the analysis of natural and synthetic androgenic steroids and their selected metabolites in aquatic environmental matrixes using direct large-volume injection (LVI) high-performance liquid chromatography (HPLC) tandem mass spectrometry (MS/MS). Method accuracy ranged from 87.6 to 108% for analytes with well-matched internal standards. Precision, quantified by relative standard deviation (RSD), was less than 12%. Detection limits for the method ranged from 1.2 to 360 ng/L. The method was demonstrated on a series of 1 h composite wastewater influent samples collected over a day with the purpose of assessing temporal profiles of androgen loads in wastewater. Testosterone, androstenedione, boldenone, and nandrolone were detected in the sample series at concentrations up to 290 ng/L and loads up to 535 mg/h. Boldenone, a synthetic androgen, had a temporal profile that was strongly correlated to testosterone, a natural human androgen, suggesting its source may be endogenous. An analysis of the sample particulate fraction revealed detectable amounts of sorbed testosterone and androstenedione. Androstenedione sorbed to the particulate fraction accounted for an estimated 5 to 7% of the total androstenedione mass.  相似文献   

7.
Ultraperformance liquid chromatography coupled to electrospray tandem mass spectrometry was used for the rapid and simultaneous analysis of 15 stimulatory drugs in water. Cocaine, amphetamine-related compounds, LSD, ketamine, PCP, fentanyl, and metabolites, among the controlled drugs, and nicotine, caffeine, and their metabolites, among the noncontrolled drugs, were studied. Chromatographic separation was achieved in less than 4.5 min, with improved peak resolution and sensitivity. Identification and quantification of the compounds of interest was performed by selected reaction monitoring, using an electrospray ionization source. Isotope dilution (except for paraxanthine) was used for quantitation. Quality parameters of the method were established, and limits of quantification were obtained for controlled drugs in surface waters from 0.1 to 3.1 ng/L and in wastewaters from 0.2 to 4.0 ng/L. Run-to-run and day-to-day precisions were evaluated in different water matrixes (Milli-Q water, surface water, wastewater). To assess the presence of these drugs in real water samples, the optimized method was applied to the analysis of wastewater and surface river water. The analysis of several samples from wastewater treatment plants in northeast Spain revealed the presence of drugs such as cocaine and amphetamine-related compounds, in both influent and effluent samples. Cocaine metabolite and MDMA (ecstasy) were also found in surface waters while nicotine and caffeine were detected in all the analyzed samples. The results obtained demonstrate that the presence of these drugs in the aquatic media must be considered a matter of environmental concern.  相似文献   

8.
Two methods have been developed that enable the determination of estrogens down to 2 ng/g in digested and activated sludge from domestic sewage treatment plants (STPs) and down to 0.2 ng/g in freshwater sediments. The method for sludge analysis consists of solvent extraction; a gel permeation chromatography (GPC) cleanup step, a 1 g silica gel column; and finally, detection by GC-ion trap MS/MS of the silylated estrogens with MSTFA. For sediments, the solvent extraction was successively followed by silica gel cleanup, solid phase enrichment (SPE), and a HPLC cleanup before derivatization and GC/MS/MS detection. Mean recoveries of the estrogens mainly exceeded 70% in sludge and 90% in sediments. In activated and digested sewage sludge, estrone and 17beta-estradiol were detected up to 37 ng/g and 49 ng/g, respectively, and 17alpha-ethinylestradiol up to 17 ng/g. The occurrence of estrogens in digested sludge indicates that estrogens can be persistent during sludge digestion. In river sediments, estrone and 17beta-estradiol were detected up to 2 ng/g (estrone), and the contraceptive 17alpha-ethinylestradiol was found with a maximum of 0.9 ng/g. Mestranol, a prodrug for 17alpha-ethinylestradiol, was not detected either in sludge or in sediments.  相似文献   

9.
A new approach to the search for residues of known and unknown estrogens in calf urine is presented. Following enzymatic deconjugation and solid-phase extraction, a minor part of the samples is screened for estrogen activity using a recently developed rapid reporter gene bioassay. The remainder of the bioactive extracts is analyzed by gradient liquid chromatography (LC) with, in parallel, bioactivity and mass spectrometric detection via effluent splitting toward a 96-well fraction collector and an electrospray quadrupole time-of-flight mass spectrometer (QTOFMS). The LC fractions in the 96-well plate are used for the detection of estrogen activity using the bioassay. The biogram obtained features a 20-s time resolution, and the suspect well numbers can be easily correlated with the LC/QTOFMS retention time. The mass spectral data from the thus assigned relevant parts of the chromatograms are background subtracted, followed by accurate mass measurement, element composition calculation, and identification. The method allows estrogen activity detection and identification of (un)known estrogens in urine at the 1-2 ng/L level, in compliance with current residue analysis performance for hormone abuse in cattle. The applicability of this LC/bioassay/QTOFMS approach for the identification of estrogens in real-life samples is demonstrated by the analysis of several calf urine samples, and preliminary data from a pig feed sample.  相似文献   

10.
A method was developed to determine nine N-nitrosamines in wastewater on the basis of solid-phase extraction and liquid chromatography mass spectrometry using a linear ion trap-orbitrap hybrid instrument at high mass resolution. Analytes and five deuterated internal standards were preconcentrated by solid-phase extraction. Positive electrospray ionization resulted in protonated molecular ions of all nitrosamines. One to three product ions were formed by collision-induced dissociation or higher energy C-trap dissociation. The signal intensity of the product ions differed up to a factor of 3 between the two techniques. The molecular ions were usually used for quantification, because of the better sensitivity, and the product ions for confirmation. An actual mass resolving power of 25 000-40 000 ensured a sufficient selectivity to distinguish all molecular and product ions from interfering background ions. Only for N-nitrosomorpholine was a coeluting isobaric molecular ion detected in wastewater samples, which, however, formed different product ions. The mass accuracy was between -12 ppm at m/z 55 and 0 ppm at m/z 205 and did not change for more than 5 ppm over a sample sequence of 20 h analysis time. The optimized method allowed quantifying nine N-nitrosamines in drinking water and wastewater samples down to method detection limits of 0.3-3.9 ng/L at instrumental detection limits of 2-14 pg on column. Recoveries over the whole method were between 75 and 125% for six compounds, but considerably lower for three compounds, probably due to strong matrix effects causing a signal suppression of up to 95% in wastewater samples. N-Nitrosodimethylamine and N-nitrosomorpholine were the most abundant compounds (3-22 ng/L) in samples from two wastewater treatment plants, another four nitrosamines (N-nitrosopyrrolidone, -piperidine, -diethylamine, and -dibutylamine) were also detected. Our study demonstrates that the LTQ Orbitrap is a powerful instrument to quantify low molecular weight compounds at the picogram level in complex matrixes with both a high sensitivity and selectivity.  相似文献   

11.
The first analytical method for the determination of 13 phosphoric acid mono- and diesters from aqueous samples is presented. The method consists of solid-phase extraction (SPE) and ion-pair liquid chromatographic separation with tri-n-butylamine coupled to electrospray ionization tandem mass spectrometry in the negative ion mode. Due to a lack of pure standards, only 3 of the 13 esters could be quantified. SPE recoveries ranged from 71 to 112% for di-n-butyl phosphate, diphenyl phosphate, and di-(2-ethylhexyl) phosphate (DEHP) with limits of quantification from 7 to 14 ng/L for 100-mL samples. At analyte concentrations >or=1 microg/L, aqueous samples can be analyzed by direct injection without extraction. In municipal wastewater, six diesters and one monoester were unambiguously identified by comparison with synthesized reference material. DEHP showed highest concentrations of 60 and 5 microg/L in raw and treated wastewater, respectively. The detection of monoethylhexyl phosphate was confirmed by LC-Q-TOF-MS analysis, and it was found at a concentration level comparable to DEHP. Laboratory degradation tests show that phosphoric acid diesters can be formed as intermediates in the microbial degradation of trialkyl phosphates that are being used as flame retardants and plasticizers.  相似文献   

12.
13.
A novel analytical method has been developed for the determination of six basic antidepressants (venlafaxine, sertraline, paroxetine, citalopram, amitriptyline, and fluoxetine) and four of their metabolites (O-desmethylvenlafaxine, desmethylsertraline, nortriptyline, and norfluoxetine) in raw sewage and roughly primary-treated wastewater. For analytical development purposes, two ion exchange solid-phase extraction cartridges were compared. Extracts were analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS) with positive-mode electrospray (+ESI) and selected reaction monitoring transitions. The choice of a basic mobile phase significantly improved the instrumental sensitivity (by up to 14-fold for norfluoxetine) relative to common +ESI acidic mobile phases. In addition to the remarkable gain in sensitivity, negligible matrix effects were also observed in the raw sewage samples. Analyte recoveries ranged from 80 to 103% and effluent detection limits from 0.048 to 0.10 ng/L. Samples collected at the Montreal Wastewater Treatment Plant showed the unequivocal presence of all the target compounds at concentrations of 2-346 ng/L. The target antidepressants were also detected in samples taken from the effluent receiving waters (i.e., the St. Lawrence River) but at lower concentrations (0.41-69 ng/L). The highly sensitive proposed method constitutes one of the best means for monitoring the environmental occurrence of tricyclic antidepressants, selective serotonin reuptake inhibitors (SSRIs), and some of their metabolites.  相似文献   

14.
The coupling of antibody-, receptor-, or enzyme-based inhibition assays postcolumn to chromatographic systems provides biological detectors with extraordinary high sensitivity and specificity. Three monoclonal antibodies (MC10E7, AD4G2, M8H5) directed against microcystins and protein phosphatase 1 (PP1) were used as off-line detectors for the HPLC separation of microcystins and nodularin in comparison to UV detection. For HPLC/ELISA coupling using antibody MC10E7, a detection limit of 0.04 ng microcystin-LR was achieved. The provisional guideline value for microcystin-LR (1 microg/L, WHO) could be monitored without prior sample concentration, in contrast to UV detection. Quantification of microcystin-LR and two cross-reactants was demonstrated. Furthermore, cross-reactivity or enzyme inhibition of new microcystins, only available in small amounts, can be determined by this method. Using a cyanobacterial extract, HPLC/ELISA coupling was compared to HPLC/UV and electrospray ionization mass spectrometry (ESI-TOFMS).  相似文献   

15.
Residues of illicit drugs and their metabolites that are excreted by humans may flow into and through wastewater treatment plants. The aim of this study was to develop a method for the determination of cocaine, amphetamines, morphine, cannabinoids, methadone, and some of their metabolites in wastewater. Composite 24-h samples from urban treatment plants were enriched with deuterated internal standards before solid-phase extraction. High-pressure liquid chromatography tandem mass spectrometry with multiple reaction monitoring was used for quantitation. Recoveries were generally higher than 80%, and limits of quantifications were in the low nanograms-per-liter range for untreated and treated wastewater. The overall variability of the method was lower than 10% for untreated and 5% for treated wastewater. The method was applied to wastewater samples coming from two treatment plants in Italy and Switzerland. Quantification ranges were found to be 0.2-1 microg/L for cocaine and its metabolite benzoylecgonine, 80-200 ng/L for morphine, 10 ng/L for 6-acetylmorphine, 60-90 ng/L for 11-nor-9-carboxy-Delta9-tetrahydrocannabinol, 10-90 ng/L for methadone and its main metabolite 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine, and lower than 20 ng/L for amphetamines. As previously reported for cocaine, this method could be useful to estimate and monitor drug consumption in the population in real time, helping social scientists and authorities to combat drug abuse.  相似文献   

16.
A method has been developed for the trace analysis of 27 compounds from a diverse group of pharmaceuticals, steroids, pesticides, and personal care products. The method employs solid-phase extraction (SPE) and liquid chromatography/tandem mass spectrometry (LC/MS/MS), using electrospray ionization (ESI) in both positive and negative modes and atmospheric pressure chemical ionization in positive mode. Unlike many previous methods, a single SPE procedure using 1 L of water coupled to a simple LC method is used for all ionization modes. Instrument detection limits for most compounds were below 1.0 pg on column with reporting limits of 1.0 ng/L in water. Recoveries for most compounds in deionized water were greater than 80%. Sulfuric acid was found to be the preferred sample preservative, and structures of all MS/MS product ions are proposed. Matrix effects from waters with a high content of treated municipal effluent were observed in both ESI modes and are discussed in the paper.  相似文献   

17.
We have developed an analytical method, consisting of ion-pair liquid chromatography coupled to electrospray ionization mass spectrometry (IP-LC-ESI-MS), for the simultaneous quantitative analysis of several key classes of polar metabolites, like nucleotides, coenzyme A esters, sugar nucleotides, and sugar bisphosphates. The use of the ion-pair agent hexylamine and optimization of the pH of the mobile phases were critical parameters in obtaining good retention and peak shapes of many of the above-mentioned polar and acidic metabolites that are impossible to analyze using standard reversed-phase LC/MS. Optimum conditions were found when using a gradient from 5 mM hexylamine in water (pH 6.3) to 90% methanol/10% 10 mM ammonium acetate (pH 8.5). The IP-LC-ESI-MS method was extensively validated by determining the linearity (R2 > 0.995), sensitivity (limit of detection 0.1-1 ng), repeatability, and reproducibility (relative standard deviation <10%). The IP-LC-ESI-MS method was shown to be a useful tool for microbial metabolomics, i.e., the comprehensive quantitative analysis of metabolites in extracts of microorganisms, and for the determination of the energy charge, i.e., the cellular energy status, as an overall quality measure for the sample workup and analytical protocols.  相似文献   

18.
A simple and accurate spectrophotometric method for determination of trace and ultra-trace amounts of Al3+ ion in tap and wastewater sample has been described. Using the eriochrome cyanine R (ECR) in the presence of N,N-dodecyltrimethylammonium bromide (DTAB) as cationic surfactant spectrophotometric determination of Al3+ ion has been carried out. The Beer's law is obeyed over the concentration range of 4-400 ng mL(-1) of Al3+ ion with the detection limits of 0.14 ng mL(-1), while the molar absorptivity of complexes is 1.19x10(5) L mol(-1) cm(-1). The influence of type and amount of surfactant, pH, and amount of ligand on sensitivity of spectrophotometric method were optimized. The method has been successfully applied for Al3+ ion determination in real sample.  相似文献   

19.
We have demonstrated the use of a simple microfabricated electrospray ionization source for coupling microfluidic chips to mass spectrometry (MS). A polymer-based microchip, coupled to a triple quadrupole mass spectrometer, has been employed for direct infusion quantitative bioanalysis of methylphenidate (Ritalin) extracted from human urine samples. The approach used a microfabricated polymer electrospray emitter to couple a microfluidic channel to a stable electrospray ionization source. The microchip was fabricated from cycloolefin plastic plate by hot embossing and thermal bonding. This microfluidic chip contained two independent microfluidic channels, integrated with two corresponding electrospray emitters and an internal gold electrode. Liquid-liquid extraction was used to prepare urine samples, spiked with methylphenidate. A trideuterated analogue of methylphenidate (methylphenidate-d(3)) was used as the internal standard for the analysis. The system showed good electrospray stability and reproducibility with different spray tips. Four different electrospray tips were used to analyze the same sample, and the results showed very small variation with a relative standard deviation of 1.4%. A standard curve prepared for methylphenidate in urine (R(2) = 0.999) was linear over the range of 0.4-800 ng/mL. The precision of the quality control samples for three different concentrations ranged from 19.1% at 20 ng/mL, 3.2% at 200 ng/mL, to 3.5% at 667 ng/mL while the accuracy was 96.3% at 20 ng/mL, 101.2% at 200 ng/mL, and 101.6% at 667 ng/mL. No system carryover was detected even when the same device was used for sequential analysis. These results suggest the potential of this microdevice for MS-based quantitative analysis in drug discovery and development.  相似文献   

20.
Highly water soluble benzene- and naphthalenesulfonates are widely used in the chemical, pharmaceutical, tannery, paper, and textile industries. In this work, Isolute ENV+ polystyrene divinylbenzene sorbent was used for the enrichment of 14 benzene- and naphthalenesulfonates from industrial wastewaters. The elution step was performed by adding 1 mL of water containing ion-pair reagent (5 mM of triethylamine (TEA) and 5 mM of acetic acid at pH 6.5) and 9 mL of methanol at 1 mL/min. The most relevant contribution was the use of ion-pair liquid chromatography followed by an orthogonal electrospray interface coupled to mass spectrometry in the negative ionization mode with postcolumn addition at 0.2 mL/min of methanol in combination with a volatile substance (triethylamine) as an ion-pair reagent. [M-H](-) ion was the base peak using low fragmentor voltages of 80 V with the electrospray interface. Significant fragmentation of the quasimolecular [M-H](-) ion occurs at high fragmentor voltage, producing [M-SO(2)H](-), [M-SO(3)H](-), and [SO(3)](?)(-) as diagnostic ions. Collision-induced dissociation of the parent ions for the benzene- and naphthalenesulfonates studied gave the [SO(3)](?)(-) fragment ion common to sulfonated compounds. At high fragmentor voltages of 150 V, [M-SO(3)H](-) ion is more abundant and therefore has a larger peak than the [M-H](-) peaks for 1,5-naphthalenedisulfonate, 2,6-naphthalenedisulfonate, 1-hydroxy-3,6-naphthalenedisulfonate, 2-hydroxy-3,6-naphthalenedisulfonate, and 2-amino-1,5-naphthalenedisulfonate. Recoveries were higher than 70%, with relative standard deviations between 1.3 and 10.7% with the exception of two naphthalenesulfonate compounds that had recoveries between 26 and 41%. Limits of detection (signal-to-noise ratio, 3) ranging from 0.6 pg to 0.13 ng (0.03-6.48 μg/L) were achieved when 150 mL of groundwater was processed. The aromatic sulfonates 3-nitrobenzenesulfonate, 4-methylbenzenesulfonate, 4-chlorobenzenesulfonate, 1-hydroxy-4-naphthalenosulfonate, 1-amino-6-naphthalenosulfonate, 1-amino-7-naphthalenosulfonate, and 1-naphthalenesulfonate and the linear alkyl benzenesulfonates C(10)-LAS and C(11)-LAS were unequivocally identified and quantitatively determined in μg/L, in wastewater samples from wastewater treatment plants and textile and tannery industries. 2-Naphthalenesulfonate was found as a major pollutant at mg/L concentration levels.  相似文献   

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