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31.
《Comptes Rendus Chimie》2015,18(10):1134-1142
Pharmaceuticals, personal care products and endocrine disruptors demonstrate huge potential to cause adverse ecological health effects at very low concentration in aquatic environment. There is a need to improve current purification technologies used in sewage and drinking-water treatment plants. This article aims at providing new insights into the recent development of natural and modified clay-based sorbents for the removal of aqueous contaminants such as pharmaceuticals and personal care products. The removal of six widely used pharmaceuticals: ibuprofen, diclofenac, ketoprofen, carbamazepine, as well as endocrine disrupting chemicals – bisphenol A and a bactericidal agent, triclosan – was examined by sorption onto eight adsorbents. Sorption was performed using natural and modified clay minerals – montmorillonite (Mt), vermiculite (VER), bentonite (B), kaolinite (K), commercial acid activated montmorillonites K10 and K30, and two carbonaceous-mineral nanocomposites, MtG5%T, BAlG3%C. This study showed that among the tested natural clays, vermiculite is the most promising sorbent for the removal of pharmaceuticals in purification processes. Among the modified clay minerals, the best results were achieved for carbonaceous bentonite and two acid activated montmorillonites K10 and K30. However, the removal of acidic pharmaceuticals on montomorillonite K10 and carbonaceous bentonite was strongly dependent on the pH value. In the case of vermiculite and acid-modified montmorillonite K30, the sorption of the selected compounds was not significantly affected by pH, which is crucial in wastewater treatment. The sorption constant divided by the specific surface area (Kd/A) is proposed to assess whether the surface area or chemical properties of the materials control the sorption process. Kd/A values were relatively high in the case of vermiculite, so it should be noticed that individual and specific surface properties of vermiculite were of crucial importance for sorption. 相似文献
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Determination of pharmaceuticals in biosolids using accelerated solvent extraction and liquid chromatography/tandem mass spectrometry 总被引:1,自引:0,他引:1
An analytical method was developed to quantitatively determine pharmaceuticals in biosolid (treated sewage sludge) from wastewater treatment plants (WWTPs). The collected biosolid samples were initially freeze dried, and grounded to obtain relatively homogenized powders. Pharmaceuticals were extracted using accelerated solvent extraction (ASE) under the optimized conditions. The optimal operation parameters, including extraction solvent, temperature, pressure, extraction time and cycles, were identified to be acetonitrile/water mixture (v/v 7:3) as extraction solvent with 3 extraction cycles (15 min for each cycle) at 100 °C and 100 bars. The extracts were cleaned up using solid-phase extraction followed by determination by liquid chromatography coupled with tandem mass spectrometry. For the 15 target pharmaceuticals commonly found in the environment, the overall method recoveries ranged from 49% to 68% for tetracyclines, 64% to 95% for sulfonamides, and 77% to 88% for other pharmaceuticals (i.e. acetaminophen, caffeine, carbamazepine, erythromycin, lincomycin and tylosin). The developed method was successfully validated and applied to the biosolid samples collected from WWTPs located in six cities in Michigan. Among the 15 target pharmaceuticals, 14 pharmaceuticals were detected in the collected biosolid samples. The average concentrations ranged from 2.6 μg/kg for lincomycin to 743.6 μg/kg for oxytetracycline. These results indicated that pharmaceuticals could survive wastewater treatment processes, and accumulate in sewage sludge and biosolids. Subsequent land application of the contaminated biosolids could lead to the dissemination of pharmaceuticals in soil and water environment, which poses potential threats to at-risk populations in the receiving ecosystems. 相似文献
34.
Sumner N 《Journal of chromatography. A》2011,1218(36):6107-6113
Experiments have been carried out to evaluate Counter Current Chromatography (CCC) as an alternative purification technique to preparative Reverse Phase High Performance Liquid Chromatography (RP-HPLC) for small molecule pharmaceuticals. The major drawback of CCC is the extensive time required in selecting the solvents to perform the separation. This is equivalent to choosing both the stationary phase and the mobile phase at the same time. In RP-HPLC it is a simple matter of deciding on the gradient, most samples can be purified on a C18 column with a water:acetonitrile gradient. The majority of the initial work was based on a standard test set of commercially available compounds, developed within our group to evaluate the performance of the HPLC apparatus and the column prior to the start of work each day. The work carried out on CCC has shown that the technique offers similar capabilities and can be carried out using similar protocols to RP-HPLC. CCC also has some advantages over RP-HPLC and can be regarded as a valuable addition to the chromatography toolbox. 相似文献
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The potent Diels-Alder diene, phencyclone, 1, reacts with N-pentafluorophenylmaleimide, 2, to form an adduct, 3, characterized by 1H, 13C, and 19F NMR at 300, 75 and 282 MHz, respectively. The one-dimensional (1D) and two-dimensional (2D) 1H and 13C NMR spectra of 3 at ambient temperatures imply a slow exchange limit (SEL) regime with respect to rotation of the unsubstituted bridgehead phenyl groups about severely hindered C(sp2)-C(sp3) bonds. Major non-bonded interactions are expected between the ortho protons of the C6H5 groups and H-1, 8 of the phenanthrenoid moiety of 3. 19F 1D and 2D (COSY) NMR spectra show that the SEL regime also obtains for rotation about the N-C6F5 bond of 3, with five separate fluorine signals seen, consistent with a preferred conformation in which the C6F5 may lie roughly perpendicular to the plane of the pyrrolidinedione moiety, and may be in the mirror symmetry plane of 3. The results are considered relevant to hindered aryl rotations in numerous Pharmaceuticals. Selected spectral data for 2 and precursors are also presented. 相似文献
37.
Abstract The Diels-Alder adduct of phencyclone, compound 1, with p-fluoranil, compound 3, has been prepared in refluxing toluene. The adduct, compound 2, has been examined by 1H, 13C and 19F NMR spectroscopy at 300, 75 and 282 MHz, respectively. At ambient temperature, the unsubstituted bridgehead phenyl groups in adduct 2 are found to exhibit hindered rotation, resulting in slow exchange limit (SEL) 1H NMR spectra. Full aryl proton assignments are made based on 1D and 2D (COSY45) NMR. The 19F NMR (proton coupled) reveals one of the two 19F signals to be a triplet. This resonance collapses to a singlet in the proton decoupled 19F spectrum, implying an unexpected long range 1H-19F coupling. For the 13C NMR spectrum, tentative assignments are presented. Data for compound 2 as a model compound for drugs are discussed in terms of the hindered aryl rotation and evidence of magnetic anisotrppic effects. 相似文献
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39.
Determination of antimicrobial residues and metabolites in the aquatic environment by liquid chromatography tandem mass spectrometry 总被引:2,自引:0,他引:2
Antimicrobials are used in large quantities in human and veterinary medicine. Their environmental occurrence is of particular
concern due to the potential spread and maintenance of bacterial resistance. After intake by the organisms, the unchanged
drug and its metabolized forms are excreted and enter wastewater treatment plants where they are mostly incompletely eliminated,
and are therefore eventually released into the aquatic environment. The reliable detection of several antimicrobials in different
environmental aqueous compartments is the result of great improvements achieved in analytical chemistry. This article provides
an overview of the more outstanding analytical methods based on liquid chromatography tandem mass spectrometry, developed
and applied to determine antimicrobial residues and metabolites present in surface, waste, and ground waters.
相似文献
40.
Multi-residue analytical methods using LC-tandem MS for the determination of pharmaceuticals in environmental and wastewater samples: a review 总被引:1,自引:0,他引:1
Multi-residue analytical methodologies are becoming the preferred and required tools against single group analysis, as they
provide wider knowledge about the occurrence of pharmaceuticals in the environment necessary for further study of their removal,
partition and ultimate fate. However, simultaneous analysis of compounds from different groups with quite different physico-chemical
characteristics requires a compromise in the selection of experimental conditions, which in some cases are not the best conditions
for all the analytes studied. In this article, an overview of analytical methodologies focusing on the simultaneous determination
of acidic, neutral and basic compounds belonging to different therapeutical classes is presented. The state-of-the-art of
LC-MS/MS for multi-class analysis is reviewed, highlighting the specific requirements for such analysis. 相似文献