The Experts below are selected from a list of 132 Experts worldwide ranked by ideXlab platform
Ai Jia - One of the best experts on this subject based on the ideXlab platform.
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Trace analysis of quinolone and fluoroquinolone antibiotics from wastewaters by liquid chromatography-electrospray tandem mass spectrometry.
Journal of Chromatography A, 2008Co-Authors: Yang Xiao, Hong Chang, Ai JiaAbstract:Abstract A sensitive liquid chromatography–electrospray tandem mass spectrometry method, combined with solid-phase extraction and a weak cation exchange cartridge cleanup, was established for twenty quinolone and fluoroquinolone antibiotics (pipemidic Acid, flerofloxacin, ofloxacin, pefloxacin, enoxacin, norfloxacin, ciprofloxacin, danofloxacin, enrofloxacin, lomefloxacin, difloxacin, sarafloxacin, gatifloxacin, sparfloxacin, moxifloxacin, cinoxacin, oxolinic Acid, nalidixic Acid, flumequine, and Piromidic Acid) in influent, effluent, and river waters. For the various water matrices considered, the overall recoveries were from 64% to 127% except for Piromidic Acid (27–33%), and no obvious matrix effect was observed. The method detection limits for the twenty target antibiotics in the influent, effluent, and surface water samples were 1.6–50 ng/L, 0.6–50 ng/L, and 0.8–50 ng/L, respectively. This method was applied to analyze residual quinolone and fluoroquinolone antibiotics in wastewater and surface water samples from Beijing, China. Eight antibiotics (12 (pipemidic Acid)–1208 ng/L (ofloxacin)) were detected in wastewater, and seven (1.3 (lomefloxacin)–535 ng/L (ofloxacin)) were detected in surface water samples. Gatifloxacin, a 4th generation fluoroquinolone antibiotic, was detected for the first time in influent (111 ng/L), effluent (56 ng/L), and river water (16–42 ng/L).
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Trace analysis of quinolone and fluoroquinolone antibiotics from wastewaters by liquid chromatography-electrospray tandem mass spectrometry
journal of chromatography a, 2008Co-Authors: Xiao Yang, Ai Jia, Chang Hong, Hu JianyingAbstract:A sensitive liquid chromatography-electrospray tandem mass spectrometry method, combined with solid-phase extraction and a weak cation exchange cartridge cleanup, was established for twenty quinolone and fluoroquinolone antibiotics (pipemidic Acid, flerofloxacin, ofloxacin, pefloxacin, enoxacin, norfloxacin, ciprofloxacin, danofloxacin, enrofloxacin, lomefloxacin, difloxacin, sarafloxacin, gatifloxacin, sparfloxacin, moxifloxacin, cinoxacin, oxolinic Acid, nalidixic Acid, flumequine, and Piromidic Acid) in influent, effluent, and river waters. For the various water matrices considered, the overall recoveries were from 64% to 127% except for Piromidic Acid (27-33%), and no obvious matrix effect was observed. The method detection limits for the twenty target antibiotics in the influent, effluent, and surface water samples were 1.6-50 ng/L, 0.6-50 ng/L, and 0.8-50 ng/L, respectively. This method was applied to analyze residual quinolone and fluoroquinolone antibiotics in wastewater and surface water samples from Beijing, China. Eight antibiotics (12 (pipemidic Acid)-1208 ng/L (ofloxacin)) were detected in wastewater, and seven (1.3 (lomefloxacin)-535 ng/L (ofloxacin)) were detected in surface water samples. Gatifloxacin, a 4th generation fluoroquinolone antibiotic, was detected for the first time in influent (111 ng/L), effluent (56 ng/L), and river water (16-42 ng/L). 2008 Elsevier B.V. All rights reserved.Biochemical Research MethodsChemistry, AnalyticalSCI(E)EIPubMed76ARTICLE1-2100-108121
Mark R. Madson - One of the best experts on this subject based on the ideXlab platform.
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Laser diode thermal desorption mass spectrometry for the analysis of quinolone antibiotic residues in aquacultured seafood
Rapid communications in mass spectrometry : RCM, 2012Co-Authors: Jack J. Lohne, Sherri B Turnipseed, Wendy C. Andersen, Susan B. Clark, Mark R. MadsonAbstract:RATIONALE Veterinary drug residue analysis of meat and seafood products is an important part of national regulatory agency food safety programs to ensure that consumers are not exposed to potentially dangerous substances. Complex tissue matrices often require lengthy extraction and analysis procedures to identify improper animal drug treatment. Direct and rapid analysis mass spectrometry techniques have the potential to increase regulatory sample analysis speed by eliminating liquid chromatographic separation. METHODS Flumequine, oxolinic Acid, and nalidixic Acid were extracted from catfish, shrimp, and salmon using Acidified acetonitrile. Extracts were concentrated, dried onto metal sample wells, then rapidly desorbed (6 s) with an infrared diode laser for analysis by laser diode thermal desorption atmospheric pressure chemical ionization with tandem mass spectrometry (LDTD-MS/MS). Analysis was conducted in selected reaction monitoring mode using Piromidic Acid as internal standard. RESULTS Six-point calibration curves for each compound in extracted matrix were linear with r2 correlation greater than 0.99. The method was validated by analyzing 23 negative samples and 116 fortified samples at concentrations of 10, 20, 50, 100, and 600 ng/g. Average recoveries of fortified samples were greater than 77% with method detection levels ranging from 2 to 7 ng/g. Three product ion transitions were acquired per analyte to identify each residue. CONCLUSIONS A rapid method for quinolone analysis in fish muscle was developed using LDTD-MS/MS. The total analysis time was less than 30 s per sample; quinolone residues were detected below 10 ng/g and in most cases residue identity was confirmed. This represents the first application of LDTD to tissue extract analysis. Published 2012. This article is a US Government work and is in the public domain in the USA.
Meg Croft - One of the best experts on this subject based on the ideXlab platform.
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Determination of quinolones and fluoroquinolones in fish tissue and seafood by high-performance liquid chromatography with electrospray ionisation tandem mass spectrometric detection.
Journal of chromatography. A, 2002Co-Authors: Lesley Johnston, Lindsey G. Mackay, Meg CroftAbstract:Abstract A reversed-phase high-performance liquid chromatographic method with tandem mass-spectrometric detection was developed and validated for the simultaneous analysis of eight quinolones and fluoroquinolones (oxolinic Acid, flumequine, Piromidic Acid, enrofloxacin, ciprofloxacin, danofloxacin, sarafloxacin and orbifloxacin) in trout tissue, prawns and abalone. The analytes were extracted from homogenised tissue using acetonitrile and the extracts subjected to an automated two-stage solid-phase extraction process involving polymeric reversed-phase and anion-exchange cartridges. Good recoveries were obtained for all analytes and the limit of quantification was 5 μg/kg (10 μg/kg for ciprofloxacin). The limit of detection was 1–3 μg/kg, depending on the analyte and matrix. Confirmation of the identity of a residue was achieved by further tandem mass-spectrometric analysis. A procedure for estimating the uncertainty associated with the measurement is presented.
José Luis Vilchez - One of the best experts on this subject based on the ideXlab platform.
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Capillary zone electrophoretic determination of tosufloxacin and trovafloxacin in urine
Chromatographia, 2002Co-Authors: José Luis Vilchez, Avismelsi Prieto, Lilia Araujo, Alberto NavalónAbstract:A simple and rapid capillary zone electrophoretic method with UV detection has been developed for determination of tosufloxacin and trovafloxacin. The separation was performed in fused-silica capillaries (57 cm length × 75μm i.d.); the running buffer was 35 mm borate + 35 mm phosphate buffer solution, pH 8.6, containing 6% ( v/v ) acetonitrile. The applied potential was 15 kV, the temperature 30°C, and detection was at 262 nm. Piromidic Acid was used as the internal standard. Response was linearly dependent on concentration in the range 1.0–120.0 μg mL^−1 and the detection limit was 0.2 μg mL^−1 for both compounds. The analysis was highly reproducible ( RSD between 3.41 and 1.25%). The method was applied to the determination of tosufloxacin and trovafloxacin in human and rat urine. The method was validated by using HPLC as a reference method. Recovery was between 96.8 and 102%.
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Determination of grepafloxacin and clinafloxacin by capillary zone electrophoresis.
Journal of chromatography. B Analytical technologies in the biomedical and life sciences, 2002Co-Authors: Alberto Navalón, Lilia Araujo, Avismelsi Prieto, José Luis VilchezAbstract:A simple and rapid capillary zone electrophoresis determination method with UV detection of grepafloxacin and clinafloxacin has been developed. The separation was performed in 35 mM borate-35 mM phosphate buffer solution (pH 8.6), containing 6% (v/v) of acetonitrile. Analyses were realised using fused-silica capillaries (57 cm length x 75 microm I.D.) and the operating conditions were: 15 kV applied voltage, 30 degrees C and detection at 279 nm. Piromidic Acid was used as an internal standard. The linear concentration range of application was 1.0-120.0 microg ml(-1) for both compounds, with a detection limit of 0.2 microg ml(-1) for grepafloxacin and 0.3 microg ml(-1) for clinafloxacin. The analysis yielded good reproducibility (RSD between 3.37 and 1.74%). It was applied to the determination of grepafloxacin and clinafloxacin in human and rat urine samples. The method was validated using HPLC as a reference method. Recovery levels were between 94.5 and 103%.
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Determination of grepafloxacin and clinafloxacin by capillary zone electrophoresis.
Journal of Chromatography B, 2002Co-Authors: Alberto Navalón, Lilia Araujo, Avismelsi Prieto, José Luis VilchezAbstract:Abstract A simple and rapid capillary zone electrophoresis determination method with UV detection of grepafloxacin and clinafloxacin has been developed. The separation was performed in 35 m M borate–35 m M phosphate buffer solution (pH 8.6), containing 6% (v/v) of acetonitrile. Analyses were realised using fused-silica capillaries (57 cm length×75 μm I.D.) and the operating conditions were: 15 kV applied voltage, 30 °C and detection at 279 nm. Piromidic Acid was used as an internal standard. The linear concentration range of application was 1.0–120.0 μg ml −1 for both compounds, with a detection limit of 0.2 μg ml −1 for grepafloxacin and 0.3 μg ml −1 for clinafloxacin. The analysis yielded good reproducibility (RSD between 3.37 and 1.74%). It was applied to the determination of grepafloxacin and clinafloxacin in human and rat urine samples. The method was validated using HPLC as a reference method. Recovery levels were between 94.5 and 103%.
Alberto Navalón - One of the best experts on this subject based on the ideXlab platform.
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Determination of quinolone residues in raw cow milk. Application of polar stir-bars and ultra-high performance liquid chromatography–tandem mass spectrometry
2018Co-Authors: Rocío Rodríguez-gómez, Alberto Navalón, María Teresa García-córcoles, Morsina Çipa, Dolores Barrón, Alberto Zafra-gómezAbstract:Seventeen quinolone antibiotics were determined in cows’ milk. A method of high sensitivity, selectivity and accuracy was developed. Accuracy (trueness and precision), linearity, sensitivity, selectivity, decision limit and detection capability were established following the recommendations of the Commission Decision 2002/657/EC and the Food and Drug Administration (FDA) guideline. The use of polar stir-bar sorptive extraction (SBSE) prior to UHPLC-MS/MS analysis is proposed. The variables that affect SBSE were optimised using multivariate optimisation strategies. The ionic strength, the extraction time and the sample volume were studied. pH and stir-bar coating (polydimethylsiloxane, PDMS, and polyethyleneglycol modified silicone, PEG) were studied. PEG showed the best extraction yield at pH 6. For validation, a matrix-matched calibration and a recovery assay were carried out. Limits of quantification from 0.5 μg kg−1 for nalidixic Acid, flumequine and Piromidic Acid, to 4.0 μg kg−1 for sarafloxacin were calculated. The precision (%, RSD) was lower than 15% for all antibiotics. Recoveries in fortified samples were between 88 and 114%.
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Capillary zone electrophoretic determination of tosufloxacin and trovafloxacin in urine
Chromatographia, 2002Co-Authors: José Luis Vilchez, Avismelsi Prieto, Lilia Araujo, Alberto NavalónAbstract:A simple and rapid capillary zone electrophoretic method with UV detection has been developed for determination of tosufloxacin and trovafloxacin. The separation was performed in fused-silica capillaries (57 cm length × 75μm i.d.); the running buffer was 35 mm borate + 35 mm phosphate buffer solution, pH 8.6, containing 6% ( v/v ) acetonitrile. The applied potential was 15 kV, the temperature 30°C, and detection was at 262 nm. Piromidic Acid was used as the internal standard. Response was linearly dependent on concentration in the range 1.0–120.0 μg mL^−1 and the detection limit was 0.2 μg mL^−1 for both compounds. The analysis was highly reproducible ( RSD between 3.41 and 1.25%). The method was applied to the determination of tosufloxacin and trovafloxacin in human and rat urine. The method was validated by using HPLC as a reference method. Recovery was between 96.8 and 102%.
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Determination of grepafloxacin and clinafloxacin by capillary zone electrophoresis.
Journal of chromatography. B Analytical technologies in the biomedical and life sciences, 2002Co-Authors: Alberto Navalón, Lilia Araujo, Avismelsi Prieto, José Luis VilchezAbstract:A simple and rapid capillary zone electrophoresis determination method with UV detection of grepafloxacin and clinafloxacin has been developed. The separation was performed in 35 mM borate-35 mM phosphate buffer solution (pH 8.6), containing 6% (v/v) of acetonitrile. Analyses were realised using fused-silica capillaries (57 cm length x 75 microm I.D.) and the operating conditions were: 15 kV applied voltage, 30 degrees C and detection at 279 nm. Piromidic Acid was used as an internal standard. The linear concentration range of application was 1.0-120.0 microg ml(-1) for both compounds, with a detection limit of 0.2 microg ml(-1) for grepafloxacin and 0.3 microg ml(-1) for clinafloxacin. The analysis yielded good reproducibility (RSD between 3.37 and 1.74%). It was applied to the determination of grepafloxacin and clinafloxacin in human and rat urine samples. The method was validated using HPLC as a reference method. Recovery levels were between 94.5 and 103%.
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Determination of grepafloxacin and clinafloxacin by capillary zone electrophoresis.
Journal of Chromatography B, 2002Co-Authors: Alberto Navalón, Lilia Araujo, Avismelsi Prieto, José Luis VilchezAbstract:Abstract A simple and rapid capillary zone electrophoresis determination method with UV detection of grepafloxacin and clinafloxacin has been developed. The separation was performed in 35 m M borate–35 m M phosphate buffer solution (pH 8.6), containing 6% (v/v) of acetonitrile. Analyses were realised using fused-silica capillaries (57 cm length×75 μm I.D.) and the operating conditions were: 15 kV applied voltage, 30 °C and detection at 279 nm. Piromidic Acid was used as an internal standard. The linear concentration range of application was 1.0–120.0 μg ml −1 for both compounds, with a detection limit of 0.2 μg ml −1 for grepafloxacin and 0.3 μg ml −1 for clinafloxacin. The analysis yielded good reproducibility (RSD between 3.37 and 1.74%). It was applied to the determination of grepafloxacin and clinafloxacin in human and rat urine samples. The method was validated using HPLC as a reference method. Recovery levels were between 94.5 and 103%.