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Occurrence and risk assessment of pesticides and pharmaceuticals in viticulture impacted watersheds from Northwest Spain. CHEMOSPHERE 2023; 341:140098. [PMID: 37683952 DOI: 10.1016/j.chemosphere.2023.140098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 09/04/2023] [Accepted: 09/05/2023] [Indexed: 09/10/2023]
Abstract
An automated analytical methodology was developed, validated and applied to monitor 73 organic pollutants (pesticides and pharmaceuticals) in surface and groundwater samples obtained in watersheds from an intensive viticulture, rural region, in the Northwest of Spain. Filtered samples were concentrated using a reusable solid-phase extraction sorbent, on-line combined with liquid chromatography tandem mass spectrometry (LC-MS/MS). The analytical procedure achieved limits of quantification between 1 ng L-1 and 10 ng L-1, with a throughput of 2 samples hour-1, providing accurate recoveries for more than 90% of the 73 selected compounds, using calibration solutions prepared in ultrapure water (in presence of methanol and formic acid) as neat solvent. The distribution and the concentrations of pesticides in small streams impacted by discharges of treated municipal wastewaters were different in rural and residential areas. On the other hand, pharmaceuticals showed a similar distribution in both streams. In surface waters from viticulture impacted watersheds, with a limited influence of municipal wastewaters, pulses of pesticides were noticed, with values above 100 ng L-1 for several fungicides. Cardiovascular pharmaceuticals, psychiatric drugs and/or their transformation products were also ubiquitous in these samples, with low, but relatively stable concentrations among sampling campaigns. Within the suite of investigated compounds, maximum pesticide residues remained below their predicted-non effect concentration (PNEC) in all samples. On the other hand, the environmental concentrations of the cardiovascular drug olmesartan stayed systematically above its PNEC in fresh water samples.
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Direct, automated and sensitive determination of glyphosate and related anionic pesticides in environmental water samples using solid-phase extraction on-line combined with liquid chromatography tandem mass spectrometry. J Chromatogr A 2023; 1687:463697. [PMID: 36508766 DOI: 10.1016/j.chroma.2022.463697] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 11/29/2022] [Accepted: 11/30/2022] [Indexed: 12/12/2022]
Abstract
An automated procedure for the simultaneous determination of six anionic pesticides, including glyphosate (GLY) and its transformation product aminomethylphosphonic acid (AMPA), was developed and applied to the analysis of environmental water samples. The proposed method combines on-line concentration of water samples (0.160 mL), with compounds separation in an anion-exchange liquid chromatography (LC) column, followed by their selective determination by tandem mass spectrometry (MS/MS). The global procedure was completed in 25 min, providing limits of quantification (LOQs) between 5 ng L-1 and 20 ng L-1, with reduced effect of the surface water matrix in the efficiency of process (SPE and ionization yields). The method was applied to the analysis of grab samples obtained from three watersheds, in two rural and one residential area, in Galicia (Northwest Spain). Out of six investigated compounds, Fosetyl, AMPA and GLY were noticed in the set of processed samples. Their detection frequencies increased from 12% (Fosetyl) to 88% (AMPA). Median concentrations followed the same trend varying from 9 ng L-1 (Fosetyl) to 44 ng L-1 (AMPA). The higher levels and the large seasonal variations in the residues of the latter species were noticed in small rivers affected by discharges of municipal sewage treatment plants (STPs).
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Approaches to liquid chromatography tandem mass spectrometry assessment of glyphosate residues in wine. Anal Bioanal Chem 2022; 414:1445-1455. [PMID: 34820706 PMCID: PMC8724176 DOI: 10.1007/s00216-021-03775-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 10/25/2021] [Accepted: 11/04/2021] [Indexed: 11/30/2022]
Abstract
The performance of two different analytical methodologies to investigate the presence of glyphosate (GLY) and aminomethylphosphonic acid (AMPA) residues in wine samples was evaluated. Transformation of compounds in their fluorene-9-methyloxycarbonyl derivatives permitted their separation under reversed-phase liquid chromatography with tandem mass spectrometry (LC-MS/MS) determination. Although the wine matrix severely impaired the efficiency of GLY derivatization, this drawback was solved using a molecularly imprinted sorbent for the previous, selective extraction of GLY and AMPA from wine. Alternatively, the use of a strong anionic exchange, polyvinyl alcohol-based LC column, turned to be the most effective alternative for direct determination of both compounds in diluted wine samples. The chromatographic behavior of this column and the magnitude of matrix effects observed during analysis of diluted wine samples were significantly affected by the composition of the mobile phase. Under final working conditions, this column permitted the separation of AMPA and the fungicide fosetyl (which shows common transitions in tandem MS/MS methods), it improved significantly the sample throughput versus extraction-derivatization-purification method, and it allowed the use of solvent-based calibration standards. Both analytical procedures provided similar limits of quantification (LOQs) for GLY (0.5-1.0 ng mL-1), while the multistep method was 8 times more sensitive to AMPA than the direct procedure. GLY residues stayed above method LOQs in 70% of the processed wines; however, concentrations measured in 95% of positive samples remained 100 times below the maximum residue limit (MRL) set for GLY in vinification grapes.
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Determination of pesticide residues in wine by solid-phase extraction on-line combined with liquid chromatography tandem mass spectrometry. J Food Compost Anal 2021. [DOI: 10.1016/j.jfca.2021.104184] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Assessment of direct analysis in real time accurate mass spectrometry for the determination of triclosan in complex matrices. Anal Bioanal Chem 2021; 413:6355-6364. [PMID: 34378070 PMCID: PMC8487875 DOI: 10.1007/s00216-021-03591-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 07/27/2021] [Accepted: 07/29/2021] [Indexed: 11/25/2022]
Abstract
In this work, the applicability of direct analysis in real time coupled to accurate mass spectrometry (DART-MS) to the quantitative determination of triclosan (TCS) in samples with increasing complexity, from personal care products to extracts from sewage, is investigated. In the first term, DART-MS spectra of TCS as free phenol and as derivatized species are characterized; thereafter, the effects of several instrumental variables in the detectability of TCS (i.e., temperature, solvent, and compound holder) are discussed. Under final selected conditions, TCS was determined from its [M-H]− ions, without need of derivatization, attaining an instrumental limit of quantification of 5 ng mL−1, with a linear response range up to 1000 ng mL−1. Complex matrices, such as solid-phase extracts obtained from environmental water samples, moderately inhibited the ionization efficiency of TCS, with signal attenuation percentages in the range of 6 to 57%, depending on the sample type and on the concentration factor provided by the SPE procedure. The accuracy of results obtained by DART-MS was evaluated using liquid chromatography (LC) with MS detection; in both cases, a time-of-flight (TOF) MS instrument was employed for the selective determination of the [M−H]− ions of TCS (m/z values 286.9439 and 288.9410) using a mass window of 20 ppm. DART-MS did not only provide enough sensitivity to detect the presence of TCS in environmental samples (raw and treated wastewater as well as freeze-dried sludge), but also measured concentrations matched those determined by LC-ESI-TOF-MS, with only slightly higher standard deviations. During analysis of personal care products, containing much higher concentrations of TCS in a less complex matrix, both techniques were equivalent in terms of accuracy and precision. Graphical abstract ![]()
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Identification and determination of emerging pollutants in sewage sludge driven by UPLC-QTOF-MS data mining. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 778:146256. [PMID: 33714823 DOI: 10.1016/j.scitotenv.2021.146256] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 02/28/2021] [Accepted: 02/28/2021] [Indexed: 06/12/2023]
Abstract
Sludge from sewage treatment plants (STPs) is recognized as a sink of moderate to high lipophilic compounds resistant to biodegradation. Herein, we investigate the presence of emerging pollutants in sewage sludge combining the information provided by mass spectrometry detection, following ultra-performance liquid chromatography (UPLC), with the use of an accurate spectral database of pesticides and pharmaceuticals. In a first step, the performance of matrix solid-phase dispersion, as sample preparation technique, and two non-target data acquisition strategies (data dependent, DDA, and data independent analysis modes, DIA), used in combination with a UPLC quadrupole time-of-flight system, are assessed using a selection of deuterated compounds added either to freeze-dried sludge samples, or to sludge extracts. Possibilities and limitations of both modes are discussed. Following the DDA approach, a group of 68 micropollutants was identified in sludge from different STPs. Some of them are reported in this compartment for the first time. Finally, semi-quantitative concentration data are reported for a group of 37 pollutants in samples obtained from 16 STPs. Out of them, 10 pharmaceuticals, showing detection frequencies and median sludge residues above 50% and 100 ng g-1, respectively; are highlighted as pollutants to be monitored in sludge in order to understand their behaviour during the wastewater treatment.
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Supercritical fluid chromatography-mass spectrometric determination of chiral fungicides in viticulture-related samples. J Chromatogr A 2021; 1644:462124. [PMID: 33839447 DOI: 10.1016/j.chroma.2021.462124] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 03/22/2021] [Accepted: 03/25/2021] [Indexed: 12/31/2022]
Abstract
Supercritical fluid chromatography (SFC), combined with mass spectrometry (MS), was employed for the determination of five chiral fungicides, from two different chemical families (acylalanine and triazol) in wine and vineyard soils. The effect of different SFC parameters (stationary phase, chiral selector, mobile phase modifier and additive) in the resolution between enantiomers and in the efficiency of compounds ionization at the electrospray source (ESI) was thorougly described. Under final working conditions, chiral separations of selected fungicides were achieved using two different SFC-MS methods, with an analysis time of 10 min and resolution factors from 1.05 to 2.45 between enantiomers. In combination with solid-phase extraction and pressurized liquid extraction, they permitted the enantiomeric determination of target compounds in wine and vineyard soils with limits of quantification in the low ppb range (between 0.5 and 2.5 ng mL-1, and from 1.3 to 6.5 ng g-1, for wine and soil, respectively), and overall recoveries above 80%, calculated using solvent-based standards. For azolic fungicides (tebuconazole, myclobutanil and penconazole) soil dissipation and transfer from vines to wines were non-enantioselective processes. Data obtained for acylalanine compounds confirmed the application of metalaxyl (MET) to vines as racemate and as the R-enantiomer. The enantiomeric fractions (MET-S/(MET-S+MET-R)) of this fungicide in vineyard soils varied from 0.01 to 0.96; moreover, laboratory degradation experiments showed that the relative dissipation rates of MET enantiomers varied depending on the type of soil.
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Assessment of UV combined with free chlorine for removal of valsartan acid from water samples. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 762:143173. [PMID: 33139010 DOI: 10.1016/j.scitotenv.2020.143173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 10/12/2020] [Accepted: 10/14/2020] [Indexed: 06/11/2023]
Abstract
Valsartan acid (VALA) is a persistent and mobile pollutant, ubiquitously distributed in the aquatic environment. Herein, we assessed the efficiency of UV/free chlorine for the removal of this pollutant. Degradation experiments were performed using different water samples, considering several pH values and concentrations of inorganic anions. Time-course of VALA was measured by injection of different reaction time aliquots in a liquid chromatography (LC) triple quadrupole (QqQ) mass spectrometry (MS) system, whilst the study of potential transformation products (TPs) was evaluated by LC combined with a hybrid quadrupole time-of-flight (QTOF) MS system. Formation of volatile disinfection by-products (DBPs) was investigated by gas chromatography (GC) with TOF-MS detection. Compared to free chlorine treatment and UV photolysis, the combination of both parameters significantly enhanced the degradability of VALA. At neutral pH, UV/free chlorine was also more effective than UV/H2O2 to remove VALA from spiked water solutions. Three TPs of VALA were tentatively identified by LC-QTOF-MS, although only one was stable in the UV/free chlorine media. As regards volatile DBPs, the formation of chloroform, dichloroacetonitrile, di- and trichloroacetic acid was noticed. The mass yield of DBPs formation from VALA varied from 0.3% (dichloroacetonitrile) to 1.1% (chloroform). The efficiency of UV/free chlorine was first investigated in spiked solutions with increasing complexities: ultrapure, river and treated wastewater. Thereafter, the feasibility of reducing VALA levels in polluted river water was demonstrated.
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Multiresidue procedure to assess the occurrence and dissipation of fungicides and insecticides in vineyard soils from Northwest Spain. CHEMOSPHERE 2020; 261:127696. [PMID: 32711239 DOI: 10.1016/j.chemosphere.2020.127696] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 07/08/2020] [Accepted: 07/12/2020] [Indexed: 06/11/2023]
Abstract
The presence of fungicide and insecticide residues in wine has been largely investigated. However, few studies have addressed the persistence of these compounds in vineyard soils. In this research, we investigate the residues of a relevant number of fungicides and insecticides in vineyard soils, obtained in the Northwest of Spain, at the beginning of each agriculture campaign. Moreover, the dissipation of species showing high concentrations were monitored during the non-vegetative period of vines, in order to understand their soil evolution between application campaigns. To this end, a multiresidue analytical procedure based on pressurized liquid extraction (PLE) followed by liquid chromatography tandem mass spectrometry (LC-MS/MS) determination was first optimized. Under final working conditions, absolute recoveries in the range from 70 to 130% were achieved for 44 out of 51 selected compounds. The method LOQs remained at the low ng g-1 level (0.2-13 ng g-1) with a linear response range up to 500 ng g-1. Analysis of vineyard soils, collected during a 2-year period, from a geographic area with a high incidence of fungal diseases, demonstrated the presence of relevant concentrations of several fungicides and the insecticide imidacloprid (IMI) in this compartment. Most compounds detected at the end of the application season remained in soil at the beginning of the next year campaign. Among them, six fungicides (dimethomorph, boscalid, myclobutanil, penconazole, pyraclostrobin and pyrimethanil) and IMI showed average dissipation efficiencies below 50%, so they pose a potential to accumulate in this kind of soils.
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Residues of anilinopyrimidine fungicides and suspected metabolites in wine samples. J Chromatogr A 2020; 1622:461104. [DOI: 10.1016/j.chroma.2020.461104] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 04/01/2020] [Accepted: 04/02/2020] [Indexed: 10/24/2022]
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Portable dehumidifiers condensed water: A novel matrix for the screening of semi-volatile compounds in indoor air. CHEMOSPHERE 2020; 251:126346. [PMID: 32135372 DOI: 10.1016/j.chemosphere.2020.126346] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 02/20/2020] [Accepted: 02/25/2020] [Indexed: 06/10/2023]
Abstract
The comprehensive identification of organic species existing in indoor environments is a key issue to understand their impact in human health. This study proposes the analysis of condensed water samples, collected with portable dehumidifiers, to characterize semi-volatile compounds in the gas phase of confined areas. Water samples are concentrated by solid-phase extraction (SPE). The obtained extracts are analysed by gas chromatography (GC) time-of-flight mass spectrometry (TOF-MS), following a non-target screening data mining approach. In first term, spectra of deconvoluted compounds are compared with those in NIST low resolution library; thereafter, tentative identifications are verified using an in-house database of accurate electron ionization (EI) MS spectra. Chromatographic (retention index) and spectral data are combined for unambiguous species identification. The potential of condensed water samples to reflect changes in the composition of indoor atmospheres, the match between data obtained using different dehumidifiers, and the relative concentration efficiency of condensed water compared to that attained by active sampling of moderate air volumes are discussed. A total of 141 semi-volatile compounds were identified (98 confirmed against authentic standards) in a set of 21 samples obtained from different homes and working places. This list contains more than 40 fragrances (including several potential allergens), solvents and intermediates in the production of polymeric materials, plasticizers and flame retardants.
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Evaluation of supercritical fluid chromatography accurate mass spectrometry for neonicotinoid compounds determination in wine samples. J Chromatogr A 2020; 1620:460963. [DOI: 10.1016/j.chroma.2020.460963] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 02/07/2020] [Accepted: 02/07/2020] [Indexed: 02/06/2023]
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Chronic liver disease and impaired hepatic glycogen metabolism in argininosuccinate lyase deficiency. JCI Insight 2020; 5:132342. [PMID: 31990680 PMCID: PMC7101134 DOI: 10.1172/jci.insight.132342] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 01/15/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUNDLiver disease in urea cycle disorders (UCDs) ranges from hepatomegaly and chronic hepatocellular injury to cirrhosis and end-stage liver disease. However, the prevalence and underlying mechanisms are unclear.METHODSWe estimated the prevalence of chronic hepatocellular injury in UCDs using data from a multicenter, longitudinal, natural history study. We also used ultrasound with shear wave elastography and FibroTest to evaluate liver stiffness and markers of fibrosis in individuals with argininosuccinate lyase deficiency (ASLD), a disorder with high prevalence of elevated serum alanine aminotransferase (ALT). To understand the human observations, we evaluated the hepatic phenotype of the AslNeo/Neo mouse model of ASLD.RESULTSWe demonstrate a high prevalence of elevated ALT in ASLD (37%). Hyperammonemia and use of nitrogen-scavenging agents, 2 markers of disease severity, were significantly (P < 0.001 and P = 0.001, respectively) associated with elevated ALT in ASLD. In addition, ultrasound with shear wave elastography and FibroTest revealed increased echogenicity and liver stiffness, even in individuals with ASLD and normal aminotransferases. The AslNeo/Neo mice mimic the human disorder with hepatomegaly, elevated aminotransferases, and excessive hepatic glycogen noted before death (3-5 weeks of age). This excessive hepatic glycogen is associated with impaired hepatic glycogenolysis and decreased glycogen phosphorylase and is rescued with helper-dependent adenovirus expressing Asl using a liver-specific (ApoE) promoter.CONCLUSIONOur results link urea cycle dysfunction and impaired hepatic glucose metabolism and identify a mouse model of liver disease in the setting of urea cycle dysfunction.TRIAL REGISTRATIONThis study has been registered at ClinicalTrials.gov (NCT03721367, NCT00237315).FUNDINGFunding was provided by NIH, Burroughs Wellcome Fund, NUCDF, Genzyme/ACMG Foundation, and CPRIT.
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Selective Determination of Methyl Mercury in Biological Samples by Means of Programmed Temperature Gas Chromatography. J AOAC Int 2020. [DOI: 10.1093/jaoac/76.3.608] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract
A programmed temperature gas chromatographic method is presented by which it is possible to carry out routine analysis of methyl mercury in biological samples prepared according to the AOAC official first action recommendations without the need for preliminary treatment of the columns. This method greatly extends the life of the columns as well as the useful time for analysis; it has good linearity and repeatability. With the proposed method a total of 36 samples can be analyzed daily.
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Robustness assessment in computer-assisted liquid chromatography procedures based on desirability functions. J Chromatogr A 2020; 1609:460439. [DOI: 10.1016/j.chroma.2019.460439] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 08/04/2019] [Accepted: 08/06/2019] [Indexed: 10/26/2022]
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Assessment of gas chromatography time-of-flight mass spectrometry for the screening of semi-volatile compounds in indoor dust. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 688:162-173. [PMID: 31229814 DOI: 10.1016/j.scitotenv.2019.06.192] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 05/14/2019] [Accepted: 06/12/2019] [Indexed: 06/09/2023]
Abstract
Indoor dust contains a complex mixture of anthropogenic and synthetic compounds closely related to dermal and respiratory diseases. Target methods have been developed for the quantification of distinct groups of substances in dust samples; however, the comprehensive characterization of the different species existing in this matrix remains a challenging issue. Herein, we assess the performance of gas chromatography (GC) time-of-flight mass spectrometry (TOF-MS), using electron ionization (EI), for the screening of compounds present in indoor dust. Samples are processed by pressurized-liquid extraction (PLE) before GC-EI-TOF-MS analysis. The study proposes a data mining workflow for the non-target identification of species contained in dust extracts, aided by preliminary comparison with nominal resolution EI-MS spectra in the NIST17 library. The possibilities, and the limitations, of the above approach are discussed and the identities of >75 compounds are confirmed by comparison with authentic standards in dust from indoor environments. Some species, such as indigo, phthalic anhydride, 2,4-toluene di-isocyanate, phthalimide, certain UV absorbers and octyl isothiazolinone, identified in this research, have not been previously considered in target methods dealing with dust analysis. The study also evaluates two different algorithms for the suspected-target screening of dust extracts using a customized library of accurate EI-MS spectra. Finally, a semi-quantitative estimation of the range of concentrations for a group of 44 pollutants in a set of 27 dust samples is provided.
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Direct analysis in real time accurate mass spectrometry determination of bisphenol A in thermal printing paper. Talanta 2019; 205:120086. [PMID: 31450440 DOI: 10.1016/j.talanta.2019.06.086] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 06/20/2019] [Accepted: 06/24/2019] [Indexed: 10/26/2022]
Abstract
Contact with thermal printing paper is a relevant source of dermal exposure to unbonded bisphenol A (BPA). In order to limit this exposure route, the European Union has introduced a drastic reduction in the maximum allowed concentration of BPA in thermal paper produced after beginning of year 2020. This study investigates the suitability of direct analysis in real time (DART), combined with accurate mass spectrometry, as a faster alternative to chromatography-based methods for the quantitative determination of BPA, and three analogues species, in receipts and tickets usually printed on thermal paper. The ionization efficiency of these compounds is evaluated under different conditions, and the effect of instrumental parameters of the DART source in the observed responses is discussed. The yield of the DART desorption-ionization process was greatly improved when compounds are previously converted into their acetyl derivatives; thereafter, the temperature of electronically excited helium atoms was the most relevant of the evaluated instrumental parameters. Under optimized conditions, the reported method provided recoveries in the range from 90 to 110%, a limit of quantification of 0.004% (w:w), well below the maximum concentration established after 2020 for BPA (0.02%, w:w), and permitted to perform duplicate determinations of each sample extract with a response time around 1 min. The accuracy of BPA levels found in non-spiked samples was confirmed using GC-EI-MS as reference technique. BPA was systematically noticed in the processed samples with concentrations ranging from 0.005% to more than 6%.
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Selective determination of sartan drugs in environmental water samples by mixed-mode solid-phase extraction and liquid chromatography tandem mass spectrometry. CHEMOSPHERE 2019; 224:562-571. [PMID: 30836251 DOI: 10.1016/j.chemosphere.2019.02.137] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 02/12/2019] [Accepted: 02/22/2019] [Indexed: 06/09/2023]
Abstract
Herein, a method for the simultaneous determination of the currently prescribed sartan drugs (eprosartan, EPR; olmesartan, OLM; losartan, LOS; candesartan, CAN; telmisartan, TEL; irbesartan, IRB; and valsartan, VAL), and the biodegradation product valsartan acid (VALA), in water samples (raw and treated wastewater, river and tap water) was developed. Solid-phase extraction (SPE) and ultra-performance liquid chromatography (UPLC) tandem mass spectrometry (MS/MS) were employed as concentration and determination techniques, respectively. Different sorbents and elution solvents were tested for sample preparation. Under optimized conditions, samples at neutral pH (6-8 units) were concentrated using mixed-mode (reversed-phase and anionic exchange) cartridges. Thereafter, the sorbent was washed with 5 mL of a methanol: water (1:1) solution, dried under a nitrogen stream and compounds were eluted with 2 mL of methanol: NH3 (98:2). The accuracy of the method (accounting for SPE efficiency and matrix effects during electrospray ionization) was investigated using solvent-based calibration standards. Global recoveries, obtained for different water matrices (tap, river, treated and raw wastewater), ranged from 82% to 134%, with standard deviations between 2 and 18%. LOQs varied from 2 to 50 ng L-1. Analysis of un-spiked samples confirmed: (1) the incomplete removal of sartans at sewage treatment plants (STPs), (2) the formation of VALA during municipal water treatment, and (3) the presence of VALA in the processed tap water samples. Additional findings of the current study are the detection of hydroxylated derivatives of the sartan drugs IRB and LOS in wastewater, and the E-Z isomerization of EPR in environmental water samples.
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Effects of Aspirin on Growth Factor Release From Freshly Isolated Leukocyte-Rich Platelet-Rich Plasma in Healthy Men: A Prospective Fixed-Sequence Controlled Laboratory Study. Am J Sports Med 2019; 47:1223-1229. [PMID: 30888847 DOI: 10.1177/0363546519827294] [Citation(s) in RCA: 95] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND The benefits of platelet-rich plasma (PRP) are believed to be in part dependent on growth factor release after platelet activation. Platelet activation is complex and involves multiple mechanisms. One important mechanism is driven by cyclooxygenase 1 (COX-1)-mediated conversion of arachidonic acid (AA) to precursor prostaglandins that then mediate proinflammatory responses that trigger growth factor release. Acetylsalicylic acid (ASA; also known as aspirin) is known to irreversibly inhibit COX-1, thereby blocking AA-mediated signaling; however, it is unclear whether ASA use alters growth factor release from freshly isolated PRP. PURPOSE To assess the effects of low-dose ASA use on activation of growth factor release from freshly isolated human PRP via AA and thrombin (TBN). STUDY DESIGN Controlled laboratory study. METHODS Twelve healthy men underwent blood collection and leukocyte-rich PRP (LR-PRP) preparation through a double-spin protocol to obtain baseline whole blood and PRP counts the same day. PRP was aliquoted into 3 groups: nonactivated, AA activated, and TBN activated. Immediately after activation, the concentrations of transforming growth factor β1 (TGF-β1), vascular endothelial growth factor (VEGF), and platelet-derived growth factor AB (PDGF-AB) were measured using enzyme-linked immunosorbent assays (ELISAs). The same 12 participants were then placed on an 81-mg daily dose of oral ASA for 14 days. Repeat characterization of whole blood and PRP analyses was done on day 14, followed by repeat ELISAs of growth factors under the same nonactivated and activated settings as previously stated. RESULTS Fourteen days of daily ASA had no effect on the number of platelets and leukocytes measured in whole blood and LR-PRP. Compared with nonactivated LR-PRP, AA- and TBN-mediated activation led to significant release of VEGF and PDGF-AB. In contrast, release of TGF-β1 from LR-PRP was observed only with activation by AA, not with TBN. Consistent with its inhibitory role in AA signaling, ASA significantly inhibited AA-mediated release of all 3 growth factors measured in this study. Although ASA had no effect on TBN-mediated release of VEGF and TGF-β1 from LR-PRP, ASA did partially block TBN-mediated release of PDGF-AB, although the mechanism remains unclear. CONCLUSION Daily use of low-dose ASA reduces VEGF, PDGF-AB, and TGF-β1 expression in freshly isolated human LR-PRP when activated with AA. CLINICAL RELEVANCE Reduction in growth factor release attributed to daily use of low-dose ASA or other COX inhibitors can be mitigated when PRP samples are activated with TBN. Clinical studies are needed to determine whether activation before PRP injection is needed in all applications where ASA is in use and to what extent ASA may inhibit growth factor release in vivo at the site of injury.
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Free chlorine reactions of angiotensin II receptor antagonists: Kinetics study, transformation products elucidation and in-silico ecotoxicity assessment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 647:1000-1010. [PMID: 30180308 DOI: 10.1016/j.scitotenv.2018.08.082] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 08/03/2018] [Accepted: 08/05/2018] [Indexed: 06/08/2023]
Abstract
Angiotensin II receptor antagonists (ARA II) are widely employed in the treatment of hypertension-related diseases. Because of their partial metabolization and limited biodegradability, these drugs have become ubiquitous pollutants in the aquatic environment, including surface water. This research evaluated the reactivity of the ARA II drugs: irbesartan (IRB), losartan (LOS) telmisartan (TEL) and valsartan (VAL) with free chlorine. Responses of parent compounds and their transformation products (TPs) were followed by liquid chromatography (LC) with quadrupole (Q) time-of-flight (TOF) mass spectrometry. Degradation experiments were carried out using ultrapure and river water samples, adjusted at different pHs and, in some cases, adding a small amount (ng mL-1 level) of bromide salts. Whilst TEL and VAL remained stable in presence of relatively high concentrations of free chlorine (10 mg L-1), IRB and LOS were removed according to a pseudo-first order kinetics model. Considering an initial chlorine concentration of 10 mg L-1, their half-lives varied between 6 and 734 min, depending mostly on the water pH. IRB reacted with free chlorine through hydroxylation processes, with and without molecular cleavage and re-arrangements in the imidazolone ring. Its TPs showed a lower in-silico predicted toxicity than the parent drug. In case of LOS, two major competitive degradation routes were identified. They involved replacement of the methanol group attached to the imidazole cycle by chlorine or bromine, and the cleavage of this cycle with removal of the chlorinated carbon and the nitrogen in alpha position. The TPs generated following the first route are predicted to be more toxic than LOS.
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Fabric phase sorptive extraction followed by ultra-performance liquid chromatography-tandem mass spectrometry for the determination of fungicides and insecticides in wine. J Chromatogr A 2018; 1584:13-23. [PMID: 30502037 DOI: 10.1016/j.chroma.2018.11.025] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 11/02/2018] [Accepted: 11/15/2018] [Indexed: 12/31/2022]
Abstract
In this work, fabric phase sorptive extraction (FPSE) is investigated for the extraction and preconcentration of ultra-trace level residues of fungicides (19 compounds) and insecticides (3 species) in wine samples. Subsequently, the preconcentrated analytes are selectively determined using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Parameters affecting the efficiency and repeatability of the extraction are evaluated in depth; moreover, the proposed method is characterized in terms of linear response range, trueness, precision and limits of quantification (LOQs). The set-up of the extraction process and the type of coating were the variables exerting the most prominent effects in the repeatability and the yield of the extraction, respectively. Under optimized conditions, samples (10 mL of wine diluted with the same volume of ultrapure water) were extracted with a small amount of cellulose fabric (3 discs with 4 mm of diameter: total surface 0.38 cm2) coated with a sol-gel polyethylene glycol sorbent (sorbent amount 3.3 mg), immersed in the diluted sample, without being in direct contact with the PTFE covered magnetic stir bar. Following the overnight extraction step, analytes were quantitatively recovered using only 0.3 mL of an ACN-MeOH (80:20) mixture. Under equilibrium sampling conditions, the linear response range of the method varied from 0.2 to 200 ng mL-1, with limits of quantification (LOQs) between 0.03 and 0.3 ng mL-1. Relative recoveries ranged from 77 ± 6% to 118 ± 4%, and from 87 ± 4% to 121 ± 6% for red and white wines, respectively. Application of the optimized method to commercial wines demonstrated the existence of up to 9 out of 22 investigated compounds in the same wine sample. The compound identified at the highest concentration was iprovalicarb (IPR), with a value of 130 ± 9 ng mL-1 in a commercial white wine.
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Combinatorial Prg4 and Il-1ra Gene Therapy Protects Against Hyperalgesia and Cartilage Degeneration in Post-Traumatic Osteoarthritis. Hum Gene Ther 2018; 30:225-235. [PMID: 30070147 DOI: 10.1089/hum.2018.106] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Osteoarthritis (OA) is a degenerative disease of synovial joints characterized by progressive loss of articular cartilage, subchondral bone remodeling, and intra-articular inflammation with synovitis that results in chronic pain and motor impairment. Despite the economic and health impacts, current medical therapies are targeted at symptomatic relief of OA and fail to alter its progression. Given the complexity of OA pathogenesis, we hypothesized that a combinatorial gene therapy approach, designed to inhibit inflammation with interleukin-1 receptor antagonist (IL-1Ra) while promoting chondroprotection using lubricin (PRG4), would improve preservation of the joint compared to monotherapy alone. Employing two surgical techniques to model mild, moderate and severe posttraumatic OA, we found that combined delivery of helper-dependent adenoviruses (HDVs), expressing IL-1Ra and PRG4, preserved articular cartilage better than either monotherapy in both models as demonstrated by preservation of articular cartilage volume and surface area. This improved protection was associated with increased expression of proanabolic and cartilage matrix genes together with decreased expression of catabolic genes and inflammatory mediators. In addition to improvements in joint tissues, this combinatorial gene therapy prolonged protection against thermal hyperalgesia compared to either monotherapy. Taken together, our results show that a combinatorial strategy is superior to monotherapeutic approaches for treatment of posttraumatic OA.
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Evaluation of the aqueous phototransformation routes of phenyl ethyl azolic fungicides by liquid chromatography accurate mass spectrometry. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 615:942-954. [PMID: 29017135 DOI: 10.1016/j.scitotenv.2017.10.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 09/12/2017] [Accepted: 10/01/2017] [Indexed: 06/07/2023]
Abstract
Similarities and differences among the phototransformation routes of four azolic fungicides (diniconazole, DIN, imazalil, IMA; penconazole, PEN; and propiconazole, PRO) in surface water aliquots are investigated. Selected compounds share a common chemical structure consisting on dichlorophenyl and azolic rings connected through an ethylene bridge, which is substituted with different functionalities. Liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) was employed as analytical technique to follow the time-course of precursor fungicides and to detect and to identify their photo-transformation products (TPs). Under solar light, the substituents linked to the ethylene chain controlled the stability of the fungicides. Whilst PEN and PRO remained stable, DIN and IMA showed moderate reactivities, with half-lives (t1/2) of 5.1 and 33.5h, respectively. When exposed to UV (254nm) radiation, all compounds were effectively degraded with t1/2 in the range from seconds to a few minutes. Dechlorination followed by intramolecular cyclization, between phenyl and azolic rings, was identified as a common phototransformation route under UV irradiation. Depending on the length and the kind of the functionalities attached to the ethylene bridge, additional cyclization reactions are also possible. In-silico toxicity predictions pointed out to dechlorinated tricyclic TPs as the most concerning ones, with predicted lethal concentrations (LC50) in the same range as the precursor fungicides.
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Evaluation of nitrate effects in the aqueous photodegradability of selected phenolic pollutants. CHEMOSPHERE 2017; 185:127-136. [PMID: 28688846 DOI: 10.1016/j.chemosphere.2017.07.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 06/26/2017] [Accepted: 07/01/2017] [Indexed: 06/07/2023]
Abstract
The effect of nitrate in the aqueous photodegradation of five phenolic environmental pollutants (ortho-phenylphenol, OPP; methyl paraben, MeP; propyl paraben, PrP; Triclosan, TCS and bisphenol A, BPA) is evaluated. Time-course of precursor compounds and formation of transformation products (TPs) were investigated by liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). Nitrate showed a positive effect in the removal of selected pollutants. Observed TPs resulted from hydroxylation, aromatic nitration (with or without molecule cleavage) and nitro dehalogenation processes. The above reactions involved the participation of ·OH and ·NO2 radicals arising from photolysis of nitrate. Nitro TPs were produced in a different extent depending on the structure of the precursor pollutant, nitrate concentration, light source (254 nm UV and solar light) and water matrix (ultrapure, surface and urban wastewater). Some of these nitro TPs were also observed during UV irradiation of untreated and unbuffered wastewater, either naturally polluted with parent phenolic compounds or spiked with these species at the sub μg L-1 level. Nitration reactions were particularly favourable for OPP with the generated nitro TPs displaying a higher stability than the precursor molecule and the hydroxylated TPs of the same compound.
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Liquid chromatography quadrupole time-of-flight mass spectrometry identification and determination of tri- and hexaaryl chloro imidazoles in sewage sludge. JOURNAL OF MASS SPECTROMETRY : JMS 2017; 52:69-77. [PMID: 27966255 DOI: 10.1002/jms.3903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 12/05/2016] [Accepted: 12/09/2016] [Indexed: 06/06/2023]
Abstract
The identification and further quantification of 2-chloro-triarylimidazole (o-Cl-TAI) and its dimer (o-DCl-HABI) in sludge from a sewage treatment plant (STP) is reported for the first time. Liquid chromatography (LC) quadrupole time-of-flight (QTOF) mass spectrometry (MS) was used as analytical technique during screening and determination steps. Pollutants were identified following a post-run search strategy, applying the chlorine mass filter, and characterized by their accurate MS and product ion scan spectra. Finally, their identities were confirmed with authentic standards. The species (o-Cl-TAI) has been rated as potentially genotoxic and carcinogenic for mice and rats. Effects of sample preparation in the stability and the extraction efficiency of both compounds are discussed. Under final conditions, they were extracted from freeze-dried samples (0.5 g of sludge or biosolids dispersed with 2 g of C18 and packed into a polypropylene syringe) with 20 ml of methanol, which also flowed through a clean-up layer of Florisil and PSA sorbents (0.5 g each). This method attained quantitative extraction yields and limits of quantification between 4 and 10 ng/g. The pollutants o-Cl-TAI and o-DCl-HABI were ubiquitous in sludge and biosolids obtained in consecutive years from the investigated STP. Their concentrations varied from 0.02 to more than 13 μg/g (freeze-dried sample). Copyright © 2016 John Wiley & Sons, Ltd.
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Selective extraction and determination of neonicotinoid insecticides in wine by liquid chromatography–tandem mass spectrometry. J Chromatogr A 2016; 1460:9-15. [DOI: 10.1016/j.chroma.2016.07.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Revised: 07/01/2016] [Accepted: 07/04/2016] [Indexed: 01/09/2023]
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Multiclass semi-volatile compounds determination in wine by gas chromatography accurate time-of-flight mass spectrometry. J Chromatogr A 2016; 1442:107-17. [DOI: 10.1016/j.chroma.2016.03.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 03/01/2016] [Indexed: 10/22/2022]
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Restoration of the serum level of SERPINF1 does not correct the bone phenotype in Serpinf1 null mice. Mol Genet Metab 2016; 117:378-82. [PMID: 26693895 PMCID: PMC4788589 DOI: 10.1016/j.ymgme.2015.11.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 11/30/2015] [Accepted: 11/30/2015] [Indexed: 11/16/2022]
Abstract
Osteogenesis imperfecta (OI) is a group of genetic disorders characterized by bone fragility and deformity. OI type VI is unique owing to the mineralization defects observed in patient biopsies. Furthermore, it has been reported to respond less well to standard therapy with bisphosphonates [1]. Others and we have previously identified SERPINF1 mutations in patients with OI type VI. SERPINF1 encodes pigment epithelium derived factor (PEDF), a secreted collagen-binding glycoprotein that is absent in the sera of patients with OI type VI. Serpinf1 null mice show increased osteoid and decreased bone mass, and thus recapitulate the OI type VI phenotype. We tested whether restoration of circulating PEDF in the blood could correct the phenotype of OI type VI in the context of protein replacement. To do so, we utilized a helper-dependent adenoviral vector (HDAd) to express human SERPINF1 in the mouse liver and assessed whether PEDF secreted from the liver was able to rescue the bone phenotype observed in Serpinf1(-/-) mice. We confirmed that expression of SERPINF1 in the liver restored the serum level of PEDF. We also demonstrated that PEDF secreted from the liver was biologically active by showing the expected metabolic effects of increased adiposity and impaired glucose tolerance in Serpinf1(-/-) mice. Interestingly, overexpression of PEDF in vitro increased mineralization with a concomitant increase in the expression of bone gamma-carboxyglutamate protein, alkaline phosphatase and collagen, type I, alpha I, but the increased serum PEDF level did not improve the bone phenotype of Serpinf1(-/-) mice. These results suggest that PEDF may function in a context-dependent and paracrine fashion in bone homeostasis.
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Liquid chromatography quadrupole time-of-flight mass spectrometry selective determination of ochratoxin A in wine. Food Chem 2015; 199:401-8. [PMID: 26775988 DOI: 10.1016/j.foodchem.2015.12.036] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 11/11/2015] [Accepted: 12/08/2015] [Indexed: 11/29/2022]
Abstract
The performance of liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) for ochratoxin A (OTA) determination in wine is evaluated for the first time. Sample preparation was optimized to obtain quantitative recoveries at the same time that the efficiency of electrospray ionization (ESI) remained unaltered between sample extracts and calibration standards. Under final conditions, samples (20 mL) were concentrated using a reversed-phase solid-phase extraction (SPE) cartridge, followed by OTA elution with 1 mL of ethyl acetate. The absolute recoveries of the method, established against calibration standards, were 91-121% and 90-113% (without and with internal standard correction, respectively), for wines fortified at 3 concentration levels. The attained LOQ (0.05 ng mL(-1)) remained below the maximum permitted OTA concentration (2 ng mL(-1)) in dry wines. The method was applied to different samples, with OTA being found in some dessert wines at concentrations below 1 ng mL(-1). The ethyl ester of OTA (OTC) could be identified in the same wine samples from its accurate full product ion spectra.
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Determination of the cardiac drug amiodarone and its N-desethyl metabolite in sludge samples. J Chromatogr A 2015; 1394:62-70. [DOI: 10.1016/j.chroma.2015.03.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 03/06/2015] [Accepted: 03/09/2015] [Indexed: 12/22/2022]
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Simplified matrix solid phase dispersion procedure for the determination of parabens and benzophenone-ultraviolet filters in human placental tissue samples. J Chromatogr A 2014; 1371:39-47. [DOI: 10.1016/j.chroma.2014.10.063] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 09/26/2014] [Accepted: 10/22/2014] [Indexed: 11/24/2022]
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Assessment of dispersive liquid–liquid microextraction conditions for gas chromatography time-of-flight mass spectrometry identification of organic compounds in honey. J Chromatogr A 2014; 1368:26-36. [DOI: 10.1016/j.chroma.2014.09.057] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 09/22/2014] [Accepted: 09/23/2014] [Indexed: 01/25/2023]
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Matrix solid-phase dispersion of polybrominated diphenyl ethers and their hydroxylated and methoxylated analogues in lettuce, carrot and soil. J Chromatogr A 2014; 1360:57-65. [PMID: 25130091 DOI: 10.1016/j.chroma.2014.07.079] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Revised: 07/22/2014] [Accepted: 07/24/2014] [Indexed: 11/26/2022]
Abstract
In the present work, a novel analytical method for the simultaneous determination of ten polybrominated diphenyl ethers (PBDEs), eight methoxylated PBDEs (MeO-PBDEs) and seven hydroxylated PBDEs (OH-PBDEs) in soil, lettuce and carrot samples was developed. The procedure was based on matrix solid-phase dispersion (MSPD) followed by gas chromatography coupled to negative chemical ionization-mass spectrometry (GC-NCI-MS). Under optimum conditions, 0.5g of sample (freeze-dried in the case of lettuce and carrot samples) was dispersed with 0.5g of octadecyl-functionalized silica (C18) and 1.75g of acidified silica (10% H2SO4, w/w) was used as clean-up sorbent. A two-step fractionated elution was carried out. First, PBDEs and MeO-PBDEs were eluted in 75:25% (v/v) n-hexane/dichloromethane mixture and, then, the retained OH-PBDEs were eluted in pure dichloromethane. Both extracts were analyzed by GC-NCI-MS separately, in the case of OH-PBDEs after derivatization with N-methyl-N-(trimethylsilyl) trifluoroacetamide. The developed method was validated in terms of accuracy for soil, lettuce and carrot matrices, spiked at two fortification levels (5 and 25ngg(-1)). After correction with the corresponding surrogate, apparent recovery values (defined as the recovery obtained after correction with the corresponding surrogate) were in the 80-129% range. Precision (as relative standard deviation) in the 1-21% range and method detection limits (MDLs) in the 0.003 and 0.3ngg(-1) range for soil and in the 0.003-0.4ngg(-1) range (dry weight) for lettuce and carrot samples were obtained. For PBDEs the method was also validated with a standard reference material (SRM-2585) of house dust. Finally, the method was applied for the determination of target analytes in soil, lettuce and carrot.
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Selective determination of antimycotic drugs in environmental water samples by mixed-mode solid-phase extraction and liquid chromatography quadrupole time-of-flight mass spectrometry. J Chromatogr A 2014; 1339:42-9. [DOI: 10.1016/j.chroma.2014.02.087] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Revised: 02/24/2014] [Accepted: 02/25/2014] [Indexed: 11/27/2022]
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Determination of benzotriazoles in water samples by concurrent derivatization–dispersive liquid–liquid microextraction followed by gas chromatography–mass spectrometry. J Chromatogr A 2014; 1336:1-9. [DOI: 10.1016/j.chroma.2014.01.068] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 01/23/2014] [Accepted: 01/24/2014] [Indexed: 10/25/2022]
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Liquid chromatography quadrupole time-of-flight mass spectrometry quantification and screening of organophosphate compounds in sludge. Talanta 2013; 118:312-20. [PMID: 24274302 DOI: 10.1016/j.talanta.2013.10.024] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 10/07/2013] [Accepted: 10/16/2013] [Indexed: 10/26/2022]
Abstract
For the first time, we assess the performance of liquid chromatography (LC) quadrupole time-of-flight (QTOF) mass spectrometry (MS) for the selective quantification of eight organophosphate compounds (OPs), used as plasticizers and flame retardants additives, in sludge from urban sewage treatment plants (STPs). Moreover, the usefulness of accurate, full scan MS and MS/MS spectra to screen and to confirm the presence of additional OPs, without using reference standards, in sludge samples is discussed. Matrix solid-phase dispersion (MSPD) was used as a sample preparation technique. Under optimized conditions, MSPD provided quantitative recoveries for the group of targeted analytes, requiring just 15 mL of solvent and integrating extraction and clean-up processes in the same step. For these species, the achieved limits of quantification (LOQs) varied between 2 and 50 ng g(-1) and the efficiency of electrospray ionization (ESI) did not change significantly between pure standards and sludge extracts. Among targeted OPs, tri(chloroisopropyl) phosphate (TCPP), tributoxyethyl phosphate (TBEP) and triphenyl phosphate (TPP) were ubiquitous in sludge. The average concentrations of TCPP and TBEP stayed above 700 ng g(-1), whereas the mean value for TPP was 67 ng g(-1). Full scan, accurate spectra provided relevant clues for the screening of additional OPs, using a database containing just their empirical formulae and exact molecular weights; however, the occurrence of in-source fragmentation processes hampered the detection and correct identification of those species which did not render the expected [M+H](+) molecular ion, as was the case of 2-ethylhexyl-diphenyl phosphate (EHDPP).
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Gas chromatography quadrupole time-of-flight mass spectrometry determination of benzotriazole ultraviolet stabilizers in sludge samples. J Chromatogr A 2013; 1293:126-32. [DOI: 10.1016/j.chroma.2013.03.050] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Revised: 03/14/2013] [Accepted: 03/15/2013] [Indexed: 10/27/2022]
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Polyethersulfone solid-phase microextraction followed by liquid chromatography quadrupole time-of-flight mass spectrometry for benzotriazoles determination in water samples. J Chromatogr A 2013; 1299:40-7. [PMID: 23777835 DOI: 10.1016/j.chroma.2013.05.061] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Revised: 05/23/2013] [Accepted: 05/27/2013] [Indexed: 01/26/2023]
Abstract
A microextraction method for the determination of 1H-benzotriazole (BTri), and four polar derivatives (4 and 5-methyl-1H-benzotriazole, 4-TTri and 5-TTri; 5,6-dimethyl-1H-benzotriazole, XTri; and 5-chloro-1H-benzotriazole, 5-ClBTri), in surface and wastewater samples is presented. Analytes were pre-concentrated using a disposable, low cost polyethersulfone (PES) sorbent and further analysed by liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). Parameters affecting the efficiency of sample preparation (extraction conditions and desorption solvent) and those controlling the performance of LC-MS determination were investigated. Analytes were extracted from 15mL water samples, containing a 30% (w/v) of sodium chloride (4.5g) and adjusted at pH 4.5, using a tubular PES sorbent (5cm length×0.7mm o.d., sorbent volume 42μL). After methanol desorption and solvent exchange, benzotriazoles were determined by LC-MS, with chromatograms extracted using a mass window of 20ppm, centred in their [M+H](+) ions. The identity of chromatographic peaks was confirmed with accurate ion product scan (MS/MS) spectra. The method provided limits of quantification (LOQs) between 0.005 and 0.100μgL(-1), and relative recoveries from 81% to 124% (except for XTri in sewage samples, ca. 60%) with associated standard deviations between 2% and 9%. When compared with polydimethylsiloxane covered stir-bars (coating volume 24μL), the PES polymer achieved significant higher responses (5-20-fold) for these polar pollutants. BTri and tolyltriazoles (4-TTri and 5-TTri) were found in urban sewage and river water samples, affected by wastewater discharges, with the maximum concentration (5.9μgL(-1)) corresponding to BTri in raw wastewater.
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Chemometric-assisted method development in reversed-phase liquid chromatography. J Chromatogr A 2013; 1287:2-22. [DOI: 10.1016/j.chroma.2012.07.081] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2012] [Revised: 07/25/2012] [Accepted: 07/26/2012] [Indexed: 11/16/2022]
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Liquid chromatography time-of-flight mass spectrometry evaluation of fungicides reactivity in free chlorine containing water samples. JOURNAL OF MASS SPECTROMETRY : JMS 2013; 48:216-226. [PMID: 23378094 DOI: 10.1002/jms.3151] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2012] [Revised: 11/30/2012] [Accepted: 12/04/2012] [Indexed: 06/01/2023]
Abstract
Liquid chromatography (LC) combined with tandem mass spectrometry (MS/MS), based on the use of a hybrid quadrupole-time-of-flight mass analyzer, was used to investigate the reactivity of nine fungicides in free chlorine-containing water samples. Three of the selected compounds (fenhexamid, FEN; pyrimethanil, PYR; and cyprodinil, CYP) displayed a poor stability in presence of moderate chlorine levels; thus, the effects of different parameters on their half-lives (t(1/2)) were evaluated. Sample pH, bromide traces, and the water matrix affected their relative stabilities. Despite such variations, the three fungicides are degraded at significant rates not only in ultrapure, but also in surface water spiked with chlorine levels up to 2 µg ml(-1), and when mixed with chlorinated tap water, generating several transformation products (TPs). The time-course of precursor species and their TPs was followed in the LC-MS mode, using the information contained in accurate, full scan mass spectra (MS) to propose the empirical formulae of TPs. Thereafter, their ion product scan (MS/MS) spectra were considered to set their chemical structures; allowing, in some cases, to distinguish between isomeric TPs. The reaction pathway of FEN, the less stable fungicide, involved just an electrophilic substitution of hydrogen per chlorine, or bromine, and cleavage of the molecule to render an amide. PYR and CYP shared common reaction routes consisting of halogenation, hydroxylation, and condensation processes leading to complex mixtures of TPs, which were relatively stable to further transformations.
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Determination of hydroxylated stilbenes in wine by dispersive liquid–liquid microextraction followed by gas chromatography mass spectrometry. J Chromatogr A 2012; 1258:21-9. [DOI: 10.1016/j.chroma.2012.08.037] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Revised: 08/09/2012] [Accepted: 08/10/2012] [Indexed: 02/04/2023]
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Dispersive liquid–liquid microextraction with non-halogenated extractants for trihalomethanes determination in tap and swimming pool water. Talanta 2012; 99:846-52. [PMID: 22967632 DOI: 10.1016/j.talanta.2012.07.041] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2012] [Revised: 07/11/2012] [Accepted: 07/15/2012] [Indexed: 10/28/2022]
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43
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Assessment of benzophenone-4 reactivity with free chlorine by liquid chromatography quadrupole time-of-flight mass spectrometry. Anal Chim Acta 2012; 743:101-10. [DOI: 10.1016/j.aca.2012.07.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2012] [Revised: 06/26/2012] [Accepted: 07/08/2012] [Indexed: 10/28/2022]
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Cytokine-conditioned dendritic cells induce humoral tolerance to protein therapy in mice. Hum Gene Ther 2012; 23:769-80. [PMID: 22468961 DOI: 10.1089/hum.2011.225] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
A major obstacle in the genetic therapy of inherited metabolic disease is host immune responses to the therapeutic protein. This is best exemplified by inhibitor formation in the protein therapy for hemophilia A. An approach to overcoming this is induction of immunological tolerance to the therapeutic protein. Tolerogenic dendritic cells (DCtols) have been reported to induce tolerance. In addition, cytokines such as interleukin (IL)-10 and transforming growth factor (TGF)-β(1) are known to induce tolerance. To model protein therapy, we used ovalbumin (OVA) as antigen in BALB/c mice and their transgenic derivative, DO11.10 mice. In this study we show that adoptive transfer of antigen-pulsed dendritic cells (DCs) treated with a combination of IL-10 and TGF-β(1) can suppress the antibody response in mice. Adoptive transfer of cytokine-conditioned DCs in preimmunized mice results in reduction of antibody response in the mice. Furthermore, the effect is antigen specific, as the recipient mice were able to mount a potent antibody response to the control antigen. Last, we show that TGF-β(1) and IL-10-conditioned DCs are able to inhibit anti-FVIII antibody responses in FVIII knockout (KO) mice. Analysis of the contribution of IL-10 and TGF-β(1) to the DCtol phenotype shows that IL-10 treatment of DCs is sufficient for inducing OVA-specific tolerance in BALB/c mice, but we observed a requirement for treatment with both human TGF-β(1) and human IL-10 to significantly inhibit anti-FVIII antibody responses in FVIII KO mice. This paper demonstrates that autologous cell therapy for antigen-targeted immune suppression may be developed to facilitate long-term therapy.
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Mixed-mode solid-phase extraction followed by dispersive liquid–liquid microextraction for the sensitive determination of ethylphenols in red wines. J Chromatogr A 2012; 1229:79-85. [DOI: 10.1016/j.chroma.2012.01.044] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2011] [Revised: 01/13/2012] [Accepted: 01/16/2012] [Indexed: 10/14/2022]
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A binary-like approach for the computer assisted method development of isocratic and programmed ternary solvent elutions in reversed-phase liquid chromatography. J Chromatogr Sci 2012; 50:33-42. [PMID: 22291054 DOI: 10.1093/chromsci/bmr002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
A specific tool to enable exploration of multisolvent isocratic and programmed elutions for the computer assisted method development of reversed-phase liquid chromatography separations is described. The tool is purposely identical to those used in the optimization of binary solvent systems, which are by far the most commonly used by chromatographers. Existing data from failed binary solvent optimization processes are reused to explore ternary solvent systems with a few additional isocratic and programmed runs. This allows the development of efficient retention models for ternary systems, although the work of the chromatographer remains identical to that for optimization of binary systems. The retention models are used to develop an unattended optimization process and finally, the chromatographer selects the most satisfactory solution for testing and implementing in routine analysis. The process is exemplified with a mixture of 12 compounds that cannot be separated satisfactorily in aqueous binary solvent systems with methanol and acetonitrile as modifiers.
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Dispersive liquid–liquid microextraction using non-chlorinated, lighter than water solvents for gas chromatography–mass spectrometry determination of fungicides in wine. J Chromatogr A 2011; 1218:6603-11. [DOI: 10.1016/j.chroma.2011.07.054] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2011] [Revised: 07/15/2011] [Accepted: 07/18/2011] [Indexed: 11/25/2022]
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48
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NOD2 signaling contributes to the innate immune response against helper-dependent adenovirus vectors independently of MyD88 in vivo. Hum Gene Ther 2011; 22:1071-82. [PMID: 21561248 DOI: 10.1089/hum.2011.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
We previously demonstrated that Toll-like receptor/myeloid differentiation primary response gene 88 (MyD88) signaling is required for maximal innate and acquired [T helper cell type 1 (Th1)] immune responses following systemic administration of helper-dependent adenoviral vectors (HDAds). However, MyD88-deficient mice injected with HDAdLacZ exhibited only partial reduction of innate immune cytokine expression compared with wild-type mice, suggesting MyD88-independent pathways also respond to HDAds. We now show that NOD2, a nucleotide-binding and oligomerization domain (NOD)-like receptor known to detect muramyl dipeptides in bacterial peptidoglycans, also contributes to innate responses to HDAds, but not to humoral or Th1 immune responses. We established NOD2/MyD88 double-deficient mice that, when challenged with HDAds, showed a significant reduction of the innate response compared with mice deficient for either gene singly, suggesting that NOD2 signaling contributes to the innate response independently of MyD88 signaling following systemic administration of HDAds. In addition, NOD2-deficient mice exhibited significantly higher transgene expression than did wild-type mice at an early time point (before development of an acquired response), but not at a later time point (after development of an acquired response). These results indicate that the intracellular sensor NOD2 is required for innate responses to HDAds and can limit transgene expression during early phases of infection.
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Solid-phase extraction followed by liquid chromatography quadrupole time-of-flight tandem mass spectrometry for the selective determination of fungicides in wine samples. J Chromatogr A 2011; 1218:2165-75. [PMID: 21382623 DOI: 10.1016/j.chroma.2011.02.025] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2010] [Revised: 02/09/2011] [Accepted: 02/10/2011] [Indexed: 11/15/2022]
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50
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Silicone discs as disposable enrichment probes for gas chromatography-mass spectrometry determination of UV filters in water samples. Anal Bioanal Chem 2011; 400:603-11. [DOI: 10.1007/s00216-011-4763-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2010] [Revised: 02/01/2011] [Accepted: 02/02/2011] [Indexed: 10/18/2022]
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