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1.
Anal Bioanal Chem ; 416(20): 4503-4517, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38896239

RESUMO

Residues of various highly polar pesticides and their metabolites are commonly found in numerous food products. Some of these compounds, such as glyphosate, are not only used in large amounts in agriculture, but are also controversially discussed in public. Here, we present a method, employing ion chromatography (IC) coupled to tandem mass spectrometry (IC-MS/MS), for the analyses of glyphosate, aminomethyl phosphonic acid (AMPA), N-acetyl-glyphosate (NAGly), fosetyl, and 10 further highly polar pesticides and metabolites in various plant and animal matrices following a minimal sample preparation by means of the QuPPe method. Thorough investigations showed that an AS19 column enabled the analysis of all 14 compounds within 30 min. The best sensitivity could be obtained with the make-up solvent acetonitrile being admixed to the mobile phase at a 1:2 flow rate ratio. Matrix effects were thoroughly studied in terms of ion suppression and retention time shifts. Conductivity detection was used to monitor elution profiles of matrix co-extractives in comparison with matrix effect profiles obtained by continuous post-column infusion of a mix with 13 highly polar pesticides and metabolites. These tests indicated that a fivefold dilution of QuPPe extracts was suitable for the routine analysis of samples for MRL-conformity, as it considerably reduced matrix effects maintaining sufficient sensitivity and high recovery rates in eight different commodities. The suitability of the final method for its application in routine analysis was verified by the analysis of >130 samples containing incurred residues where the results were compared with two existing LC-MS/MS methods.


Assuntos
Contaminação de Alimentos , Resíduos de Praguicidas , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Animais , Contaminação de Alimentos/análise , Resíduos de Praguicidas/análise , Praguicidas/análise , Ânions/análise , Análise de Alimentos/métodos , Cromatografia por Troca Iônica/métodos , Plantas/química
2.
Anal Methods ; 16(23): 3692-3700, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38805075

RESUMO

Polar pesticides such as anionic or ionisable compounds have always provided a challenge for analytical chemists. Methods of analysis have been developed using a range of techniques including normal phase chromatography, ion-pairing, derivatisation and HILIC or multi-mode chromatography. These work well with some of these compounds but, except for HILIC, all of them have their limitations and none of them cover the range required by legislation. Some of these compounds, glyphosate, chlorate and phosphonic acid, are found regularly in a range of food matrices, and therefore reliable methods of analysis are essential. This study describes an ion chromatography method with tandem mass spectrometry detection which not only covers the full range of compounds required by legislation but also can be expanded to include other anionic or ionisable pesticides and metabolites. These include glyphosate and its metabolites, glufosinate and its metabolites, ethephon and its metabolites as well as fosetyl aluminium, chlorate and perchlorate. The method is fully validated according to the performance criteria from the SANTE guidelines for the analysis of pesticides in food and feed over a wide range of matrices, including milk, infant formula, cereals and fruits and vegetables. Over 300 food samples have analysed as part of our routine monitoring program.


Assuntos
Grão Comestível , Frutas , Praguicidas , Espectrometria de Massas em Tandem , Verduras , Espectrometria de Massas em Tandem/métodos , Grão Comestível/química , Verduras/química , Frutas/química , Praguicidas/análise , Leite/química , Fórmulas Infantis/química , Animais , Contaminação de Alimentos/análise , Humanos , Análise de Alimentos/métodos , Resíduos de Praguicidas/análise , Ânions/análise , Glicina/análogos & derivados , Glicina/análise , Glicina/química , Cromatografia por Troca Iônica/métodos
3.
Environ Monit Assess ; 195(2): 316, 2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36670262

RESUMO

The present study has been carried out to assess the quality of groundwater and surface water resources of Thettiyar watershed, Kerala, India. Sixty-six water samples were collected during pre-monsoon (April, 2019) and monsoon (July, 2019) season, and analyzed for pH, electrical conductivity (EC), total dissolved solids (TDS), total hardness and major cations and anions and microbiological parameters as well. According to the piper diagram's plot, Ca and Mg dominate over Na among the cations, and Cl is the most prevalent anion in groundwater throughout both the studied seasons. The hydrochemical analysis of water samples revealed that all the parameters are within the permissible limit except for pH. For microbiological analysis, the samples were tested for total coliform and fecal coliform. Most of the groundwater samples collected have higher total coliform and fecal coliform (E. coli) content than the recommended count by BIS (2012). The pre-monsoon surface water samples owned a maximum number of 3700 cfu/100 ml (TNTC-too numerous to count) of total coliform and 1400 cfu/100 ml (TNTC) of fecal coliform. In monsoon, the number of total coliform and fecal coliform has increased to 3800 cfu/100 ml and 1900 cfu/100 ml respectively. E. coli and total coliform are effectively correlated with each other in both seasons, in accordance with the statistical study. Domestic, sewage dump, and other household wastes are the main sources of bacterial contamination in the study area, which in turn nourishes contaminant organisms. According to the results, the government or municipality should implement an appropriate system for managing solid waste and should take all necessary measures to clean up the study area.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Qualidade da Água , Monitoramento Ambiental/métodos , Sistemas de Informação Geográfica , Escherichia coli , Poluentes Químicos da Água/análise , Água Subterrânea/química , Ânions/análise , Água/análise , Cátions/análise , Índia
4.
Appl Radiat Isot ; 192: 110566, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36493679

RESUMO

89SrCl2 radiopharmaceuticals is mainly used for bone pain palliation in the cancer patients, is being produced in FBTR via 89Y(n, p)89Sr using yttria target. The irradiated yttria target is chemically processed in high pure quartz distilled nitric acid medium in hot cell facility, to avoid the corrosion of components of hotcell due to chloride ions while using HCl medium. Being ionic species, the purified 89Sr(II) cation in aqueous solution containing bulk nitrate and other trace anions, exists as SrXn species where X: F-, Cl-, Br-, NO3-, PO43- and SO42-, n: stoichiometric anion content. The aim of the manuscript is to standardise an efficient ultra-low level anion purification method (ppb range) for the conversion of SrXn to SrCl2 and estimate the residual anionic impurities as recommended by the appropriate source specifications for its medical application. Various methods were standardised for the removal of anions in the SrCl2 source produced by the above process which include evaporation, calcination, anion exchange column, cation exchange column as well as its combination with pre-concentration column of ion chromatography (IC) technique using 89Sr tracers as well as FBTR produced 89Sr solution. Assay of 89Sr and other anions including nitrate for the above study were accomplished using Cerenkov counting and ion chromatography respectively. Thus evaporation-calcination-column chromatography mode was finalised to obtain pure SrCl2 source free from nitrate and other anionic impurities. This is the first ever systematic study for the Radiochemical quality control of nca 89SrCl2 radiopharmaceutical produced in a fast reactor. This study also finds its application to any analytical lab as well as industry where there is a requirement of anion purification in the ppb level.


Assuntos
Nitratos , Compostos Radiofarmacêuticos , Humanos , Nitratos/análise , Nitratos/química , Cromatografia por Troca Iônica/métodos , Ânions/análise , Cátions/análise , Controle de Qualidade
5.
AAPS J ; 25(1): 3, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36414847

RESUMO

The genome content of adeno-associated virus (AAV) vectors is critical to the safety and potency of AAV-based gene therapy products. Empty capsids are considered a product-related impurity and a critical quality attribute (CQA) of the drug product, thus requiring characterization throughout the production process to demonstrate they are controlled to acceptable levels in the final drug product. Anion exchange chromatography has been used to achieve separation between empty and full capsids, but requires method development and gradient optimization for different serotypes and formulations. Here, we describe an alternative approach to quantitation that does not rely on achieving separation between empty and full capsids, but instead uses the well-established relationship between absorbance at UV A260/A280 and relation to DNA/protein content, in combination with anion-exchange chromatography to allow one to calculate the relative proportion of empty and full capsids in AAV samples from a single peak. We call this approach ACUVRA: Anion-exchange Chromatography UV-Ratio Analysis, and show the applicability of the method through a case study with recombinant AAV2 (rAAV2) process intermediates and drug substance. Method qualification and GMP validation in a quality control (QC) laboratory results show that ACUVRA is a fit-for-purpose method for process development support and characterization, while also being a QC-friendly option for GMP release testing at all stages of clinical development. Graphical abstract.


Assuntos
Capsídeo , Dependovirus , Dependovirus/genética , Capsídeo/química , Vetores Genéticos , Cromatografia , Ânions/análise , Controle de Qualidade
6.
Int J Mol Sci ; 23(20)2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36293189

RESUMO

Gene therapy is opening unprecedented opportunities for novel therapeutic approaches. Based on the concept of rescuing function mutations by co-expressing the correct gene to allow biological functions to be restored, it requires the use of viral vectors to ensure the proper delivery of therapeutic genes. In this context, recombinant adeno-associated viruses (rAAV) are the most widely used vectors. Their biomanufacturing process requires the insertion of the therapeutic gene into the rAAV (full capsids). However, a percentage of rAAV that do not contain the desired gene (empty capsids), as well as partly filled capsids, might also be produced, potentially impacting the efficiency of the therapy. Therefore, the determination of the rAAV capsids' full/empty ratio needs to be monitored to ensure consistent product quality and efficacy. Anion-exchange chromatography (AEX) can serve this need. In this contribution, thorough AEX method development, including a mobile phase, a stationary phase and gradient conditions, has highlighted its potential in supporting gene therapy. Taking advantage of the fact that viral capsids follow an "on/off" retention behavior, the application of a step gradient approach to the rAAV serotype 8 (rAAV8) allowed the unprecedented separation of rAAV8 full/empty capsids, with a resolution gain of 3.7 as compared to the resolution obtained with a fully optimized linear gradient. Finally, the developed analytical approach allowed a precise and accurate baseline separation and quantification of full and empty rAAV8 capsids, with the potential to be applied as a high-throughput quality control (QC) method.


Assuntos
Capsídeo , Dependovirus , Dependovirus/genética , Capsídeo/química , Terapia Genética , Vetores Genéticos/genética , Cromatografia , Ânions/análise
7.
J Extracell Vesicles ; 11(3): e12205, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35289089

RESUMO

The development of a new large-scale purification protocol is required for research on the reliable bioactivity and drug discovery of extracellular vesicles (EVs). To address this issue, herein, we propose an effective method for preparing high-performance exosomes (EXOs) by using an anion-exchange method. Cytotoxic T-lymphocyte (CTL) EVs from 4 L of culture supernatant through a 220 nm cut-off filter are divided into two populations at a deproteinization rate of over 99.97%, which are eluted at low (0.15 M-0.3 M) and high (0.3 M-0.5 M) NaCl concentrations (approximately 2 × 1012 and 1.5 × 1012 particles, respectively) through the anion-exchange column chromatography. The former are abundant in EXO proteins, including late endosome-associated proteins and rab-family and integrin-family proteins, and functional micro (mi) RNAs, and have bioactivity for preventing tumour metastasis by depleting mesenchymal cell populations in the primary tumour lesions. By contrast, the latter is microvesicle (MV)-like particles including DNA, core histone and ribosomal proteins, and GC-rich miRNAs with unknown function, and are easily phagocytosed by mannose receptor+ Kupffer cells. Thus, the anion-exchange method is suitable for the large-scale separation of bioactive EXOs and MV-like EVs as a cargo for dangerous nucleic acids at high-purity.


Assuntos
Exossomos , Vesículas Extracelulares , Neoplasias , Ácidos Nucleicos , Ânions/análise , Exossomos/genética , Vesículas Extracelulares/química , Humanos , Neoplasias/diagnóstico , Ácidos Nucleicos/análise
8.
Environ Geochem Health ; 43(1): 1-21, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32458268

RESUMO

The chemical quality of groundwater supplies in two high-risk area (HRA) and low-risk area (LRA) for gastric cancer in Iran was assessed through hydrogeochemical analysis and water quality indices. For this aim, Piper and Schoeller diagrams and water quality index (WQI) were applied. In addition, exposure to nitrate via drinking water and its corresponding risk were also assessed using Monte Carlo simulation technique. Data on physicochemical properties of groundwater resources were obtained from Iran Water Resources Management Company. Sampling and analysis of tap water for nitrate concentration were conducted in two cities of Shiraz (as a representative of LRA) and Ardabil (as a representative of HRA). According to Piper diagrams, the dominant hydrogeochemical facies of groundwater supplies in HRA and LRA were Na-HCO3 (43.75%) and Ca-HCO3 (41.77%), respectively. The predominant cations in groundwater resources of HRA were found to be Na+ (68.06%) and Ca2+ (31.94%). For LRA, the typical cations were in decreasing trend: Ca2+ (39.64%) > Mg2+ (18.35%) > Na+ (17.26%). For two areas, HCO3-, SO42- and Cl- were, respectively, the most frequent anions. Two-sample Wilcoxon test showed that there were statistically significant difference between two areas in terms of anions and cations concentrations (p value < 0.05). The mean of total hardness (Ca2+ + Mg2+) concentration of water supplies in LRA (528.1 mg/L) was higher than HRA (263.1 mg/L), whereas the mean of Na+ concentration was found to be lower in LRA (90.6 mg/L) compared with HRA (108.1 mg/L). The sum of nitrate intake and its risk in LRA was higher than HRA. WQI results showed that drinking water quality in HRA and LRA ranged from excellent to poor and most water resources were of a good quality class. Further studies are suggested to investigate the role of drinking water in the etiology of gastric cancer in Iran.


Assuntos
Exposição Dietética/análise , Água Subterrânea/química , Água Subterrânea/normas , Neoplasias Gástricas/epidemiologia , Poluentes Químicos da Água/análise , Ânions/análise , Cátions/análise , Água Potável/química , Água Potável/normas , Monitoramento Ambiental , Humanos , Irã (Geográfico)/epidemiologia , Nitratos/análise , Medição de Risco , Neoplasias Gástricas/induzido quimicamente
9.
Chem Soc Rev ; 50(1): 589-618, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33174897

RESUMO

Imidazolium based receptors selectively recognize anions, and have received more and more attention. In 2006 and 2010, we reviewed the mechanism and progress of imidazolium salt recognition of anions, respectively. In the past ten years, new developments have emerged in this area, including some new imidazolium motifs and the identification of a wider variety of biological anions. In this review, we discuss the progress of imidazolium receptors for the recognition of anions in the period of 2010-2019 and highlight the trends in this area. We first classify receptors based on motifs, including some newly emerging receptors, as well as new advances in existing receptor types at this stage. Then we discuss separately according to the types of anions, including ATP, GTP, DNA and RNA.


Assuntos
Trifosfato de Adenosina/análise , DNA/análise , Guanosina Trifosfato/análise , Imidazóis/química , RNA/análise , Ânions/análise , Estrutura Molecular
10.
Molecules ; 25(24)2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33322010

RESUMO

The fluorine-less noble gas containing anions OBONgO- and OCNNgO- have been studied by correlated electronic structure calculation and density functional theory. The obtained energetics indicates that for Ng = Kr and Xe, these anions should be kinetically stable at low temperature. The molecular structures and electron density distribution suggests that these anions are stabilized by ion-induced dipole interactions with charges concentrated on the electronegative OBO and OCN groups. The current study shows that in addition to the fluoride ion, polyatomic groups with strong electronic affinities can also form stable noble gas containing anions of the type Y-…NgO.


Assuntos
Ânions/análise , Ânions/química , Flúor/química , Modelos Teóricos , Gases Nobres/análise , Gases Nobres/química , Algoritmos , Elétrons , Estrutura Molecular
11.
Inorg Chem ; 59(21): 15977-15986, 2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-33047602

RESUMO

In this work, we investigate the mode of interaction of a family of fluorescent zinc complexes with HS- and H2S. Different experiments, performed by diverse spectroscopic techniques, provide evidence that HS- binds the zinc center of all the complexes under investigation. Treatment with neutral H2S exhibits a markedly different reactivity which indicates selectivity for HS- over H2S of the systems under investigation. Striking color changes, visible to the naked eye, occur when treating the systems with HS- or by an H2S flow. Accordingly, also the fluorescence is modulated by the presence of HS-, with the possible formation of multiple adducts. The results highlight the potential of the devised systems to be implemented as HS-/H2S colorimetric and fluorescent sensors. Bioimaging experiments indicate the potential of using this class of compounds as probes for the detection of H2S in living cells.


Assuntos
Complexos de Coordenação/química , Corantes Fluorescentes/química , Sulfeto de Hidrogênio/análise , Imagem Óptica , Zinco/química , Ânions/análise , Células Hep G2 , Humanos , Microscopia de Fluorescência , Estrutura Molecular
12.
Molecules ; 25(9)2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32384787

RESUMO

The Opuntia ficus indica (L.) (OFI) is used as a nutritional and pharmaceutical agent in various dietary and value added products. This study underlines the possible use of native prickly pear cladode powder as a functional ingredient for health-promoting food production. To summarise, chemical characterization of polyphenols, minerals and soluble dietary fibre was performed; furthermore, the antioxidant activity and bioaccessibility of polyphenols and minerals were assessed. Eleven compounds between phenolic acids and flavonoids were identified, with piscidic acid and isorhamnetin derivatives being the most abundant. Opuntia's dietary fibre was mainly constituted of mucilage and pectin, and was composed of arabinose, galactose, glucose, mannose, rhamnose, and xylose sugars. The polyphenols' bioaccessibility was very high: piscidic acid at 200%, eucomic and ferulic acids >110% and flavonoids from 89% to 100%. The prickly pear cladode powder is also a source of minerals, as cations (calcium, sodium, potassium and magnesium) and anions (sulphate and chloride), with high magnesium bioaccessibilty (93%). OFI powder showed good capacity of radical scavenging measured by DPPH and ABTS methods, with 740 and 775 µmol Trolox/100 g OFI, respectively. Finally, the presented results allow the consideration of this natural product as a source of several essential nutrients, with a possible use in the food industry as a functional ingredient.


Assuntos
Antioxidantes/análise , Fibras na Dieta/análise , Frutas/química , Micronutrientes/análise , Opuntia/química , Polifenóis/análise , Polissacarídeos/análise , Ânions/análise , Arabinose/análise , Benzotiazóis/química , Disponibilidade Biológica , Compostos de Bifenilo/química , Cátions/análise , Ácidos Cumáricos/análise , Flavonoides/análise , Galactose/análise , Glucose/análise , Hidroxibenzoatos/análise , Manose/análise , Minerais/análise , Pectinas/análise , Pectinas/isolamento & purificação , Picratos/química , Mucilagem Vegetal/análise , Mucilagem Vegetal/isolamento & purificação , Ramnose/análise , Ácidos Sulfônicos/química , Xilose/análise
13.
ACS Nano ; 14(3): 3434-3441, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32043877

RESUMO

Self-propelled micro- and nanomachines are at the forefront of materials research, branching into applications in biomedical science and environmental remediation. Cationic frameworks enabling the collection and delivery of anionic species (A-) are highly required, due to the large variety of life-threatening pollutants, such as radioactive technetium and carcinogenic chromium, and medicines, such as dexamethasone derivatives with negative charges. However, such autonomous moving carriers for active transport of the anions have been barely discussed. A polymeric viologen (PV++)-consisting of electroactive bicationic subunits-is utilized in a tubular autonomous microswimmer to selectively deliver A- of different sizes and charge densities. The cargo loading is based on a facile anion exchange mechanism. The packed crystal structure of PV++ allows removal of an exceptionally high quantity of anions per one microswimmer (2.55 × 10-13 mol anions per microswimmer), a critical factor often neglected regarding the real-world application of microswimmers. Notably, there was virtually no leakage of anions during the delivery process or upon keeping the loaded microswimmers under ambient conditions for at least 4 months. Multiple release mechanisms, compatible with different environments, including electrochemical, photochemical, and a metathesis reaction, with high efficiencies up to 98% are introduced. Such functional autonomous micromachines provide great promise for the next generation of functional materials for biomedical and environmental applications.


Assuntos
Cromo/análise , Dexametasona/análise , Níquel/química , Platina/química , Polímeros/química , Tecnécio/análise , Viologênios/química , Ânions/análise , Técnicas Eletroquímicas , Estrutura Molecular , Tamanho da Partícula , Técnicas de Microbalança de Cristal de Quartzo , Propriedades de Superfície
14.
J Mater Chem B ; 8(5): 1017-1025, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-31934713

RESUMO

Tumor resistance and drug-induced nephrotoxicity pose great challenges to the clinical treatment of tumors, and they also limit the clinical application of oncology drugs. Finding an effective adjuvant, which can sensitize tumor treatment, is an effective method for tumor treatment. Here, we developed a ratiometric fluorescent probe, TP-Tfs, for superoxide anion (O2˙-) detection in living cells and in vivo during the process of tumor treatment for the first time. TP-Tfs with simple synthesis steps and high yields can detect O2˙- sensitively and selectively, and the detection limit was determined to be 37 nM. Using TP-Tfs, we found that cis-diaminodichloroplatinum(ii) (DDP) was effective in treating tumors by inducing O2˙- burst. Curcumin (cum) can sensitize tumor treatment effectively by inducing more severe O2˙- burst. These results indicated that the probe TP-Tfs was a promising candidate for drug screening and tumor treatment evaluation.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Corantes Fluorescentes/química , Neoplasias Pulmonares/tratamento farmacológico , Neuroblastoma/tratamento farmacológico , Superóxidos/análise , Ânions/análise , Antineoplásicos/química , Linhagem Celular Tumoral , Cisplatino/química , Corantes Fluorescentes/síntese química , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Teste de Materiais , Estrutura Molecular , Neuroblastoma/diagnóstico por imagem , Imagem Óptica , Tamanho da Partícula , Propriedades de Superfície
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 228: 117790, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31757708

RESUMO

Two novel coumarin based fluorescent sensors CHP and CHS have been synthesized for the sequential detection of Zn2+ ion and phosphate anion (PA) in DMF/HEPES buffer medium (1/5 v/v, 10 mM, pH = 7.4). On the addition of Zn2+ ion to the solution of CHP or CHS resulted in a pronounced fluorescence enhancement, accompanying noticeable color change (under UV or daylight), while there was hardly obvious change with other competing metal ions co-existing. The detection limits (DL) of CHP and CHS toward Zn2+ were separately determined as 1.03 × 10-7 (R2 = 0.9886) and 1.87 × 10-7 (R2 = 0.9902). The PET binding processes were affirmed by spectroscopic techniques, HRMS experiments and theoretical calculations. Subsequently, the CHP-Zn2+ or CHS-Zn2+ complexes showed high selectivity fluorescence quenching toward PA by snatching Zn2+ ion from its complex and the binding processes were reversible. DLs were calculated as 2.07 × 10-7 M (R2 = 0.9928) and 2.63 × 10-7 M (R2 = 0.9954), respectively. Furthermore, the cell imaging experiments demonstrated that the sensors were capable of detecting of Zn2+ and PA in vitro cells.


Assuntos
Cumarínicos/química , Corantes Fluorescentes/química , Imagem Óptica , Fosfatos , Zinco , Animais , Ânions/análise , Ânions/metabolismo , Cátions Bivalentes/análise , Cátions Bivalentes/metabolismo , Células PC12 , Fosfatos/análise , Fosfatos/metabolismo , Ratos , Espectrometria de Fluorescência , Zinco/análise , Zinco/metabolismo
16.
Artigo em Inglês | MEDLINE | ID: mdl-31533535

RESUMO

Unconventional natural gas extraction by hydraulic fracturing requires millions of gallons of water and generates flowback water, produced water and recycled fluids of varying chemical composition. Ion chromatography (IC) is a relatively low cost and efficient means to determine the anionic composition, however, the wide range in anionic content of these fluids poses a challenge to analytical methods developed for "natural" waters. We report here that the combination of UV and conductivity detectors increased detection sensitivity (e.g., 10-50 ppb) and expanded the number of anions detectable in a single sample run. Samples from four unconventional shale gas wells, two impoundments, nine conventional oil wells, two freshwater streams and mine drainage samples were analyzed in this study. All produced water samples and impoundment samples had high chloride (17,500-103,000 mg L-1, 93,900 to 134,000 mg L-1, 27,700 and 30,700 mg L-1), bromide (178-996 mg L-1, 183-439 mg L-1, 230 and 260 mg L-1) and conductivity (38,500-160,000 µS/cm3, 95,300 to 183,000 µS/cm3, 61,500 and 103,000 µS/cm3), respectively, relative to mine drainage and freshwater stream samples. Molar ratio analysis using Cl-/Br- to Cl- and SO42-/Cl- to Br- revealed significant differences between the samples, providing a simple means for distinguishing water impacted by different sources of contamination.


Assuntos
Ânions/análise , Indústria de Petróleo e Gás/métodos , Sais/química , Águas Residuárias/química , Poluentes Químicos da Água/análise , Cromatografia , Condutividade Elétrica , Água Doce/química , Campos de Petróleo e Gás
17.
Artigo em Inglês | MEDLINE | ID: mdl-31637954

RESUMO

Identifying the types of contamination and their sources in surface and groundwater is fundamental for effective protection of private and public source waters. Here we employed mass ratio analyses of a variety of anion and cation pairs to characterize flowback, produced water, and mine drainage. These endmembers were used to evaluate the source contributions of natural surface and ground water samples. A total of 1,177 ground water and surface water samples were analyzed including high-quality source waters and waters suspected of being impacted by drilling and mining activity. We found the following chemical ratios resolved different sources of contamination: Mg/Na vs SO4/Cl; SO4/Cl vs Mg/Li; Br/SO4 vs Ba/Cl; and Br vs Mg/Li. While no single parameter or mass ratio pairing by itself was definitive it was possible to converge on a likely source of contamination using multiple lines of analytical evidence. Further, this process clarified sources in impacted samples where one or more parameters commonly considered diagnostic of specific sources (e.g., Br, Ba), were below detection limits (e.g., too dilute) or not tested for. Ultimately, movement of sample values within the mass ratio space allows tracking of changes in water quality and contamination source dynamics as the water chemistry evolves.


Assuntos
Ânions/análise , Cátions/análise , Monitoramento Ambiental/métodos , Sais/química , Poluentes Químicos da Água/análise , Água Subterrânea/química , Gás Natural , Campos de Petróleo e Gás , Indústria de Petróleo e Gás , Águas Residuárias/química
18.
Anal Chem ; 91(21): 14019-14028, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31578849

RESUMO

Drug-induced acute kidney injury (AKI), caused by renal drug metabolism, has been considered to be a major barrier in drug development and clinical treatment. Among various drugs, anticancer drugs, cisplatin, and aminoglycoside antibiotic gentamicin, are known to be able to induce excessive or unfolded accumulation of proteins in the endoplasmic reticulum (ER) of cells, leading to ER stress. Meanwhile, reactive oxygen species (ROS) are formed, and superoxide anion (O2•-), the first produced ROS, is a key species to induce the AKI. Due to the lack of appropriate tools, the early diagnosis of AKI induced by cisplatin, gentamicin, or other drugs is still a crucial challenge. Herein, we report a lanthanide complex-based ER-targetable luminescence probe for O2•-, ER-(4'-trifluoromethanesulfonyloxy-2,2':6',2''-terpyridine-6,6''-diyl)bis(methylenenitrilo)tetrakis (aceticacid) (NFTTA)-Eu3+/Tb3+, for the sensitive monitoring of drug-induced AKI via mapping the generation of O2•- in live cells and laboratory animals. Using this probe coupled with the ratiometric time-gated luminescence (RTGL) imaging technique, the changes of O2•- level in the ER of live cells induced by different stimuli were precisely monitored. More importantly, the substantial increases in O2•- levels were observed in the cisplatin- and gentamicin-induced kidney injury of mice. In addition, the protective effects of l-carnitine (LC) and epigallocatechin-3-gallate (EGCG) against cisplatin- and gentamicin-induced nephrotoxicity were visualized and elucidated for the first time. The results demonstrated the potential of ER-NFTTA-Eu3+/Tb3+ for examining and monitoring O2•- in drug-induced AKI and for providing a diagnosis and treatment of nephrotoxicity diseases.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Cisplatino/efeitos adversos , Gentamicinas/efeitos adversos , Substâncias Luminescentes/química , Medições Luminescentes , Superóxidos/análise , Animais , Ânions/análise , Linhagem Celular , Cisplatino/administração & dosagem , Cisplatino/farmacologia , Retículo Endoplasmático/efeitos dos fármacos , Gentamicinas/administração & dosagem , Gentamicinas/farmacologia , Células Hep G2 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Imagem Óptica , Fatores de Tempo
19.
Arch Environ Contam Toxicol ; 77(4): 587-593, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31359072

RESUMO

Anionic surfactants are one of the pollutants derived from particulate matter (PM) and adversely affect the health of living organisms. In this study, the compositions of surfactants extracted from PM and vehicle soot collected in an urban area were investigated. A high-volume air sampler was used to collect PM sample at urban area based on coarse (> 1.5 µm) and fine (< 1.5 µm) mode particles. Meanwhile, the vehicle soot was collected randomly from the exhaust pipe of various types of diesel and petrol vehicles using a soft brush during dry days. The concentration of anionic surfactants, such as Methylene Blue Active Substances (MBAS), was determined by the colorimetric method using UV-Vis Spectrophotometer. Morphological properties of the PM and exhaust soot sample was studied using field-emission scanning electron microscope. Results revealed that the MBAS concentration was dominated by fine mode particles (6.03 ± 3.97 µmol g-1), whereas heavy-duty vehicles, such as buses, demonstrated the highest surfactant concentration with an average value of 0.340 ± 0.180 µmol g-1. The structure of collected PM for all samples mostly appeared to be an irregular shape with the size range of ultrafine particles (0.05-0.2 µm). The emission of surfactants from diesel and petrol vehicles, especially at urban areas, should be a major concern, because they could negatively affect human health and the environment.


Assuntos
Poluentes Atmosféricos/análise , Tensoativos/análise , Emissões de Veículos/análise , Ânions/análise , Cidades , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Malásia , Microscopia Eletrônica de Varredura/instrumentação , Microscopia Eletrônica de Varredura/métodos , Tamanho da Partícula , Material Particulado/análise , Fuligem/análise , Espectrofotometria Ultravioleta
20.
Food Chem ; 298: 125028, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260995

RESUMO

A robust and sensitive method utilising a hybrid ion chromatography tandem mass spectrometry system (IC-MS/MS) for the simultaneous determination of nine (9) highly polar anionic pesticides (chlorate, ethephon, fosetyl aluminium, glufosinate, glyphosate, N-acetyl AMPA, N-acetyl glyphosate, perchlorate and phosphonic acid) in fruit and vegetables is described. Mean recoveries (n = 6) at two fortification levels ranged from 83 to 112% with %CVs in the range 3-14%. The linearity range was 0.005-0.4 mg kg-1 and R2 values were >0.99 and the sensitivity of the method allowed (20× or 30×) dilution of samples. Provision of qualitative determination of aminomethylphosphonic acid (AMPA) was also facilitated via minor modification of the chromatographic conditions. Compliance with method validation criteria, survey results from the statutory UK/EU Pesticide Residues in Food 2018 programmes i.e. pea, pineapple, melon and successful z-scores for a UK proficiency testing scheme sample (ethephon in pineapple) demonstrate successful application of this IC-MS/MS method.


Assuntos
Contaminação de Alimentos/análise , Frutas/química , Resíduos de Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Verduras/química , Ânions/análise , Ânions/química , Cromatografia Líquida/métodos , União Europeia , Análise de Alimentos/métodos , Limite de Detecção , Compostos Organofosforados , Resíduos de Praguicidas/química , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/instrumentação
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