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Fernando Ramos - One of the best experts on this subject based on the ideXlab platform.

  • development and validation of a multi Residue and multi class screening method of 44 antibiotics in salmon salmo salar using ultra high performance liquid chromatography time of flight mass spectrometry application to farmed salmon
    Journal of Chromatography A, 2019
    Co-Authors: Ana Filipa Gaspar, Andreia Freitas, Sara Leston, Joao Rosa, Jorge Luis Victoria Barbosa, Lucia Santos, Ana Sofia Vila Pouca, Fernando Ramos
    Abstract:

    A fast and sensitive multi-Residue and multiclass screening method for the simultaneous determination of 44 antimicrobials in salmon muscle, using ultra- high-performance liquid chromatography/time-of-flight mass spectrometry (UHPLC-TOF/MS), was develop and validated. Two different procedures for the extraction step were tested, and an extraction with acetonitrile, ethylenediaminetetra acetic acid (EDTA) and n-hexane proved to be the best alternative. The method was validated, in accordance with Decision 2002/657/EC, using a qualitative approach at the CCβ level. The detection of the analytes was accomplished by retention time and accurate mass, whose Maximum error should not exceed 5 ppm. All the compounds were successfully detected and identified at concentration levels corresponding to ½ Maximum Residue Limit (MRL).The screening method was applied to 39 store bought samples of farmed salmon purchased in Portugal, originating from Norway and Denmark, and no antibiotic Residues were detected.

  • multi Residue and multi class method for the determination of antibiotics in bovine muscle by ultra high performance liquid chromatography tandem mass spectrometry
    Meat Science, 2014
    Co-Authors: Andreia Freitas, Jorge Barbosa, Fernando Ramos
    Abstract:

    Abstract A multi-Residue quantitative screening method covering 41 antibiotics from 7 different families, by ultra-high-performance–liquid-chromatography tandem mass spectrometry (UHPLC–MS/MS), is described. Sulfonamides, trimethoprim, tetracyclines, macrolides, quinolones, penicillins and chloramphenicol are simultaneously detected after a simple sample preparation of bovine muscle optimized to achieve the best recovery for all compounds. A simple sample treatment was developed consisting in an extraction with a mixture of acetonitrile and ethylenediaminetetraacetic acid (EDTA), followed by a defatting step with n-hexane. The methodology was validated, in accordance with Decision 2002/657/EC by evaluating the required parameters: decision Limit (CCα), detection capability (CCβ), specificity, repeatability and reproducibility. Precision in terms of relative standard deviation was under 20% for all compounds and the recoveries between 91% and 119%. CCα and CCβ were determined according the Maximum Residue Limit (MRL) or the minimum required performance Limit (MRPL), when required.

  • multi Residue and multi class determination of antibiotics in gilthead sea bream sparus aurata by ultra high performance liquid chromatography tandem mass spectrometry
    Food Additives and Contaminants Part A-chemistry Analysis Control Exposure & Risk Assessment, 2014
    Co-Authors: Andreia Freitas, Sara Leston, Joao Rosa, M C Castilho, Jorge Luis Victoria Barbosa, Paulo Rema, Miguel ângelo Pardal, Fernando Ramos
    Abstract:

    This paper describes a method for the determination of 41 antibiotics from seven different classes in gilthead sea bream (Sparus aurata) by ultra-high-performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS). Sulfonamides, trimethoprim, tetracyclines, macrolides, quinolones, penicillins and chloramphenicol were simultaneously determined. Fourteen procedures for sample treatment were tested and an extraction with acetonitrile and ethylenediaminetetra acetic acid was found to be the best option. The methodology was validated in accordance with Decision 2002/657/EC. Precision in terms of relative standard deviation (RSD) was under 17% for all compounds, and the recoveries ranged from 92% to 111%. CCα and CCβ were determined according to the Maximum Residue Limit or the minimum required performance Limit, when necessary. The validation provided evidence that the method was suitable for application in routine analysis for the detection and confirmation of antibiotics in muscle of gilthead s...

A Abd M Elaty - One of the best experts on this subject based on the ideXlab platform.

  • residual determination and risk assessment of buprofezin in plum prunus domestica grown in open field conditions following the application of three different formulations
    Biomedical Chromatography, 2016
    Co-Authors: Md Humayun Kabir, A Abd M Elaty, Sungwoo Kim, Han Sol Lee, Md Musfiqur Rahman, Youngjun Lee, Hyung Suk Chung, Truong Lieu, Jeongheui Choi
    Abstract:

    This study was conducted to characterize the residual level and perform a risk assessment on buprofezin formulated as an emulsifiable concentrate, wettable powder, and suspension concentrate over various treatment schedules in plum (Prunus domestica). The samples were extracted with an AOAC quick, easy, cheap, effective, rugged, and safe, 'QuEChERS', method after major modifications. As intrinsic interferences were observed in blank plum samples following dispersive-solid phase extraction (consisting of primary secondary amine and C18 sorbents), amino cartridges were used for solid-phase extraction. Analysis was carried out using liquid chromatography with diode array detection and confirmed by liquid chromatography-tandem mass spectrometry. The method showed excellent linearity with determination coefficient (R(2)  = 1) and satisfactory recoveries (at two spiking levels, 0.5 and 2.5 mg/kg) between 90.98 and 94.74% with relative standard deviation (RSD) ≤8%. The Limit of quantification (0.05 mg/kg) was considerably lower than the Maximum Residue Limit (2 mg/kg) set by the Codex Alimentarius. Absolute Residue levels for emulsifiable concentrates were highest, perhaps owing to the dilution rate and adjuvant. Notably, all formulation Residues were lower than the Maximum Residue Limit, and safety data proved that the fruits are safe for consumers. Copyright © 2016 John Wiley & Sons, Ltd.

  • Residue analysis of orthosulfamuron herbicide in fatty rice using liquid chromatography tandem mass spectrometry
    Journal of Advanced Research, 2015
    Co-Authors: Jeongheui Choi, A Abd M Elaty, Md Musfiqur Rahman, So Jeong Im, Jaehan Shim
    Abstract:

    In the present study, orthosulfamuron Residues were extracted from fatty (unpolished) rice and rice straw using a modified QuEChERS method and analyzed using liquid chromatography–tandem mass spectrometry. The matrix-matched calibration was linear over the concentration ranges of 0.01–2.0 mg/kg with determination coefficient (R2) ⩾ 0.997. The recovery rates at two fortification levels (0.1 and 0.5 mg/kg) were satisfactory and ranged between 88.1% and 100.6%, with relative standard deviation (RSD) <8%. The Limit of quantitation, 0.03 mg/kg, was lower than the Maximum Residue Limit, 0.05 mg/kg, set by the Ministry of Food and Drug Safety in the Republic of Korea. The developed method was applied successfully to field samples harvested at 116 days and none of the samples were positive for the Residue.

  • development of a single step precipitation cleanup method for the determination of enrofloxacin ciprofloxacin and danofloxacin in porcine plasma
    Food Chemistry, 2011
    Co-Authors: Jeongheui Choi, A Abd M Elaty, M I R Mamun, Jonghyouk Park, Eunho Shin, Jiyeon Park, Sung Chul Shin, Jaehan Shim
    Abstract:

    In this study, we describe a newly developed and simple analytical method using high-performance liquid chromatography coupled to fluorescence detector (HPLC-FLD) for the determination of enrofloxacin, ciprofloxacin, and danofloxacin in porcine plasma. A single-step sample preparation, including extraction with acidic acetonitrile, coagulation with ammonium acetate, and centrifugation made possible the direct analysis of plasma samples without the need for any further cleanup procedure. The developed method was validated with specificity, linearity, Limit of detection (LOD), Limit of quantitation (LOQ), accuracy, and precision. All results were fully adequate. In the study using porcine plasma incurring enrofloxacin, the developed method proved capable of quantifying concentrations below its Maximum Residue Limit, and its time-course Residues were excreted within the 10-day withdrawal time.

  • dissipation behavior of lufenuron benzoylphenylurea insecticide in on chinese cabbage applied by foliar spraying under greenhouse conditions
    Bulletin of Environmental Contamination and Toxicology, 2008
    Co-Authors: Sathya Khay, Jeongheui Choi, A Abd M Elaty, M I R Mamun, Byungjun Park, A Goudah, Hochul Shin, Jaehan Shim
    Abstract:

    Chinese cabbage has long been consumed as a staple food by the Koreans in various forms of fresh, salted, or fermented as kimchi. To fulfill the off-season demand for this crop, it has become a common practice to be cultivated under greenhouse conditions. Since pesticide Residues in/on leafy vegetables have strongly concerned with food safety in the Korean society, the changes of lufenuron Residues, in/on Chinese cabbage applied by foliar spraying under greenhouse conditions was investigated. Lufenuron 5% emulsifiable concentrate (EC) was sprayed with diluted solution of recommended and double doses to the crop. The shoots of the cabbage were harvested immediately after spraying, and sequentially the harvests were conveyed to analyze the residual amounts. The deposited level of the analyte in/on Chinese cabbage under greenhouse conditions seemed to be difficult to produce the crop with 0.2 ppm of Maximum Residue Limit (MRL) of the Korea Food and Drug Administration (KFDA).

Andreia Freitas - One of the best experts on this subject based on the ideXlab platform.

  • development and validation of a multi Residue and multi class screening method of 44 antibiotics in salmon salmo salar using ultra high performance liquid chromatography time of flight mass spectrometry application to farmed salmon
    Journal of Chromatography A, 2019
    Co-Authors: Ana Filipa Gaspar, Andreia Freitas, Sara Leston, Joao Rosa, Jorge Luis Victoria Barbosa, Lucia Santos, Ana Sofia Vila Pouca, Fernando Ramos
    Abstract:

    A fast and sensitive multi-Residue and multiclass screening method for the simultaneous determination of 44 antimicrobials in salmon muscle, using ultra- high-performance liquid chromatography/time-of-flight mass spectrometry (UHPLC-TOF/MS), was develop and validated. Two different procedures for the extraction step were tested, and an extraction with acetonitrile, ethylenediaminetetra acetic acid (EDTA) and n-hexane proved to be the best alternative. The method was validated, in accordance with Decision 2002/657/EC, using a qualitative approach at the CCβ level. The detection of the analytes was accomplished by retention time and accurate mass, whose Maximum error should not exceed 5 ppm. All the compounds were successfully detected and identified at concentration levels corresponding to ½ Maximum Residue Limit (MRL).The screening method was applied to 39 store bought samples of farmed salmon purchased in Portugal, originating from Norway and Denmark, and no antibiotic Residues were detected.

  • multi Residue and multi class method for the determination of antibiotics in bovine muscle by ultra high performance liquid chromatography tandem mass spectrometry
    Meat Science, 2014
    Co-Authors: Andreia Freitas, Jorge Barbosa, Fernando Ramos
    Abstract:

    Abstract A multi-Residue quantitative screening method covering 41 antibiotics from 7 different families, by ultra-high-performance–liquid-chromatography tandem mass spectrometry (UHPLC–MS/MS), is described. Sulfonamides, trimethoprim, tetracyclines, macrolides, quinolones, penicillins and chloramphenicol are simultaneously detected after a simple sample preparation of bovine muscle optimized to achieve the best recovery for all compounds. A simple sample treatment was developed consisting in an extraction with a mixture of acetonitrile and ethylenediaminetetraacetic acid (EDTA), followed by a defatting step with n-hexane. The methodology was validated, in accordance with Decision 2002/657/EC by evaluating the required parameters: decision Limit (CCα), detection capability (CCβ), specificity, repeatability and reproducibility. Precision in terms of relative standard deviation was under 20% for all compounds and the recoveries between 91% and 119%. CCα and CCβ were determined according the Maximum Residue Limit (MRL) or the minimum required performance Limit (MRPL), when required.

  • multi Residue and multi class determination of antibiotics in gilthead sea bream sparus aurata by ultra high performance liquid chromatography tandem mass spectrometry
    Food Additives and Contaminants Part A-chemistry Analysis Control Exposure & Risk Assessment, 2014
    Co-Authors: Andreia Freitas, Sara Leston, Joao Rosa, M C Castilho, Jorge Luis Victoria Barbosa, Paulo Rema, Miguel ângelo Pardal, Fernando Ramos
    Abstract:

    This paper describes a method for the determination of 41 antibiotics from seven different classes in gilthead sea bream (Sparus aurata) by ultra-high-performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS). Sulfonamides, trimethoprim, tetracyclines, macrolides, quinolones, penicillins and chloramphenicol were simultaneously determined. Fourteen procedures for sample treatment were tested and an extraction with acetonitrile and ethylenediaminetetra acetic acid was found to be the best option. The methodology was validated in accordance with Decision 2002/657/EC. Precision in terms of relative standard deviation (RSD) was under 17% for all compounds, and the recoveries ranged from 92% to 111%. CCα and CCβ were determined according to the Maximum Residue Limit or the minimum required performance Limit, when necessary. The validation provided evidence that the method was suitable for application in routine analysis for the detection and confirmation of antibiotics in muscle of gilthead s...

Jaehan Shim - One of the best experts on this subject based on the ideXlab platform.

  • Residue analysis of orthosulfamuron herbicide in fatty rice using liquid chromatography tandem mass spectrometry
    Journal of Advanced Research, 2015
    Co-Authors: Jeongheui Choi, A Abd M Elaty, Md Musfiqur Rahman, So Jeong Im, Jaehan Shim
    Abstract:

    In the present study, orthosulfamuron Residues were extracted from fatty (unpolished) rice and rice straw using a modified QuEChERS method and analyzed using liquid chromatography–tandem mass spectrometry. The matrix-matched calibration was linear over the concentration ranges of 0.01–2.0 mg/kg with determination coefficient (R2) ⩾ 0.997. The recovery rates at two fortification levels (0.1 and 0.5 mg/kg) were satisfactory and ranged between 88.1% and 100.6%, with relative standard deviation (RSD) <8%. The Limit of quantitation, 0.03 mg/kg, was lower than the Maximum Residue Limit, 0.05 mg/kg, set by the Ministry of Food and Drug Safety in the Republic of Korea. The developed method was applied successfully to field samples harvested at 116 days and none of the samples were positive for the Residue.

  • development of a single step precipitation cleanup method for the determination of enrofloxacin ciprofloxacin and danofloxacin in porcine plasma
    Food Chemistry, 2011
    Co-Authors: Jeongheui Choi, A Abd M Elaty, M I R Mamun, Jonghyouk Park, Eunho Shin, Jiyeon Park, Sung Chul Shin, Jaehan Shim
    Abstract:

    In this study, we describe a newly developed and simple analytical method using high-performance liquid chromatography coupled to fluorescence detector (HPLC-FLD) for the determination of enrofloxacin, ciprofloxacin, and danofloxacin in porcine plasma. A single-step sample preparation, including extraction with acidic acetonitrile, coagulation with ammonium acetate, and centrifugation made possible the direct analysis of plasma samples without the need for any further cleanup procedure. The developed method was validated with specificity, linearity, Limit of detection (LOD), Limit of quantitation (LOQ), accuracy, and precision. All results were fully adequate. In the study using porcine plasma incurring enrofloxacin, the developed method proved capable of quantifying concentrations below its Maximum Residue Limit, and its time-course Residues were excreted within the 10-day withdrawal time.

  • dissipation behavior of lufenuron benzoylphenylurea insecticide in on chinese cabbage applied by foliar spraying under greenhouse conditions
    Bulletin of Environmental Contamination and Toxicology, 2008
    Co-Authors: Sathya Khay, Jeongheui Choi, A Abd M Elaty, M I R Mamun, Byungjun Park, A Goudah, Hochul Shin, Jaehan Shim
    Abstract:

    Chinese cabbage has long been consumed as a staple food by the Koreans in various forms of fresh, salted, or fermented as kimchi. To fulfill the off-season demand for this crop, it has become a common practice to be cultivated under greenhouse conditions. Since pesticide Residues in/on leafy vegetables have strongly concerned with food safety in the Korean society, the changes of lufenuron Residues, in/on Chinese cabbage applied by foliar spraying under greenhouse conditions was investigated. Lufenuron 5% emulsifiable concentrate (EC) was sprayed with diluted solution of recommended and double doses to the crop. The shoots of the cabbage were harvested immediately after spraying, and sequentially the harvests were conveyed to analyze the residual amounts. The deposited level of the analyte in/on Chinese cabbage under greenhouse conditions seemed to be difficult to produce the crop with 0.2 ppm of Maximum Residue Limit (MRL) of the Korea Food and Drug Administration (KFDA).

Jeongheui Choi - One of the best experts on this subject based on the ideXlab platform.

  • residual determination and risk assessment of buprofezin in plum prunus domestica grown in open field conditions following the application of three different formulations
    Biomedical Chromatography, 2016
    Co-Authors: Md Humayun Kabir, A Abd M Elaty, Sungwoo Kim, Han Sol Lee, Md Musfiqur Rahman, Youngjun Lee, Hyung Suk Chung, Truong Lieu, Jeongheui Choi
    Abstract:

    This study was conducted to characterize the residual level and perform a risk assessment on buprofezin formulated as an emulsifiable concentrate, wettable powder, and suspension concentrate over various treatment schedules in plum (Prunus domestica). The samples were extracted with an AOAC quick, easy, cheap, effective, rugged, and safe, 'QuEChERS', method after major modifications. As intrinsic interferences were observed in blank plum samples following dispersive-solid phase extraction (consisting of primary secondary amine and C18 sorbents), amino cartridges were used for solid-phase extraction. Analysis was carried out using liquid chromatography with diode array detection and confirmed by liquid chromatography-tandem mass spectrometry. The method showed excellent linearity with determination coefficient (R(2)  = 1) and satisfactory recoveries (at two spiking levels, 0.5 and 2.5 mg/kg) between 90.98 and 94.74% with relative standard deviation (RSD) ≤8%. The Limit of quantification (0.05 mg/kg) was considerably lower than the Maximum Residue Limit (2 mg/kg) set by the Codex Alimentarius. Absolute Residue levels for emulsifiable concentrates were highest, perhaps owing to the dilution rate and adjuvant. Notably, all formulation Residues were lower than the Maximum Residue Limit, and safety data proved that the fruits are safe for consumers. Copyright © 2016 John Wiley & Sons, Ltd.

  • Residue analysis of orthosulfamuron herbicide in fatty rice using liquid chromatography tandem mass spectrometry
    Journal of Advanced Research, 2015
    Co-Authors: Jeongheui Choi, A Abd M Elaty, Md Musfiqur Rahman, So Jeong Im, Jaehan Shim
    Abstract:

    In the present study, orthosulfamuron Residues were extracted from fatty (unpolished) rice and rice straw using a modified QuEChERS method and analyzed using liquid chromatography–tandem mass spectrometry. The matrix-matched calibration was linear over the concentration ranges of 0.01–2.0 mg/kg with determination coefficient (R2) ⩾ 0.997. The recovery rates at two fortification levels (0.1 and 0.5 mg/kg) were satisfactory and ranged between 88.1% and 100.6%, with relative standard deviation (RSD) <8%. The Limit of quantitation, 0.03 mg/kg, was lower than the Maximum Residue Limit, 0.05 mg/kg, set by the Ministry of Food and Drug Safety in the Republic of Korea. The developed method was applied successfully to field samples harvested at 116 days and none of the samples were positive for the Residue.

  • development of a single step precipitation cleanup method for the determination of enrofloxacin ciprofloxacin and danofloxacin in porcine plasma
    Food Chemistry, 2011
    Co-Authors: Jeongheui Choi, A Abd M Elaty, M I R Mamun, Jonghyouk Park, Eunho Shin, Jiyeon Park, Sung Chul Shin, Jaehan Shim
    Abstract:

    In this study, we describe a newly developed and simple analytical method using high-performance liquid chromatography coupled to fluorescence detector (HPLC-FLD) for the determination of enrofloxacin, ciprofloxacin, and danofloxacin in porcine plasma. A single-step sample preparation, including extraction with acidic acetonitrile, coagulation with ammonium acetate, and centrifugation made possible the direct analysis of plasma samples without the need for any further cleanup procedure. The developed method was validated with specificity, linearity, Limit of detection (LOD), Limit of quantitation (LOQ), accuracy, and precision. All results were fully adequate. In the study using porcine plasma incurring enrofloxacin, the developed method proved capable of quantifying concentrations below its Maximum Residue Limit, and its time-course Residues were excreted within the 10-day withdrawal time.

  • dissipation behavior of lufenuron benzoylphenylurea insecticide in on chinese cabbage applied by foliar spraying under greenhouse conditions
    Bulletin of Environmental Contamination and Toxicology, 2008
    Co-Authors: Sathya Khay, Jeongheui Choi, A Abd M Elaty, M I R Mamun, Byungjun Park, A Goudah, Hochul Shin, Jaehan Shim
    Abstract:

    Chinese cabbage has long been consumed as a staple food by the Koreans in various forms of fresh, salted, or fermented as kimchi. To fulfill the off-season demand for this crop, it has become a common practice to be cultivated under greenhouse conditions. Since pesticide Residues in/on leafy vegetables have strongly concerned with food safety in the Korean society, the changes of lufenuron Residues, in/on Chinese cabbage applied by foliar spraying under greenhouse conditions was investigated. Lufenuron 5% emulsifiable concentrate (EC) was sprayed with diluted solution of recommended and double doses to the crop. The shoots of the cabbage were harvested immediately after spraying, and sequentially the harvests were conveyed to analyze the residual amounts. The deposited level of the analyte in/on Chinese cabbage under greenhouse conditions seemed to be difficult to produce the crop with 0.2 ppm of Maximum Residue Limit (MRL) of the Korea Food and Drug Administration (KFDA).