The Experts below are selected from a list of 99 Experts worldwide ranked by ideXlab platform
Liam Regan - One of the best experts on this subject based on the ideXlab platform.
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development and validation of a rapid multi class method for the confirmation of fourteen prohibited medicinal additives in pig and poultry compound feed by liquid chromatography tandem mass spectrometry
Journal of Pharmaceutical and Biomedical Analysis, 2010Co-Authors: Mark Cronly, Patrice Behan, Barry Foley, Edward Malone, S Earley, M Gallagher, P Shearan, Liam ReganAbstract:A confirmatory method has been developed to allow for the analysis of fourteen prohibited medicinal additives in pig and poultry compound feed. These compounds are prohibited for use as feed additives although some are still authorised for use in medicated feed. Feed samples are extracted by acetonitrile with addition of sodium sulfate. The extracts undergo a hexane wash to aid with sample purification. The extracts are then evaporated to dryness and reconstituted in initial mobile phase. The samples undergo an ultracentrifugation step prior to injection onto the LC-MS/MS system and are analysed in a run time of 26 min. The LC-MS/MS system is run in MRM mode with both positive and negative electrospray ionisation. The method was validated over three days and is capable of quantitatively analysing for metronidazole, dimetridazole, ronidazole, Ipronidazole, chloramphenicol, sulfamethazine, dinitolimide, ethopabate, carbadox and clopidol. The method is also capable of qualitatively analysing for sulfadiazine, tylosin, virginiamycin and avilamycin. A level of 100 microg kg(-1) was used for validation purposes and the method is capable of analysing to this level for all the compounds. Validation criteria of trueness, precision, repeatability and reproducibility along with measurement uncertainty are calculated for all analytes.
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rapid multi class multi residue method for the confirmation of chloramphenicol and eleven nitroimidazoles in milk and honey by liquid chromatography tandem mass spectrometry lc ms
Food Additives and Contaminants Part A-chemistry Analysis Control Exposure & Risk Assessment, 2010Co-Authors: Mark Cronly, Patrice Behan, Barry Foley, Edward Malone, Sheila Martin, Michael P Doyle, Liam ReganAbstract:A confirmatory method was developed to allow for the analysis of eleven nitroimidazoles and also chloramphenicol in milk and honey samples. These compounds are classified as A6 compounds in Annex IV of Council Regulation 2377/90 (European Commission 1990) and therefore prohibited for use in animal husbandry. Milk samples were extracted by acetonitrile with the addition of NaCl; honey samples were first dissolved in water before a similar extraction. Honey extracts underwent a hexane wash to remove impurities. Both milk and honey extracts were evaporated to dryness and reconstituted in initial mobile phase. These were then injected onto a liquid chromatography-tandem mass spectrometry (LC-MS/MS) system and analysed in less than 9 min. The MS/MS was operated in multiple reaction monitoring (MRM) mode with positive and negative electrospray ionization. The method was validated in accordance with Commission Decision 2002/657/EC and is capable of analysing metronidazole, dimetridazole, ronidazole, Ipronidazole...
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rapid confirmatory method for the determination of 11 nitroimidazoles in egg using liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2009Co-Authors: Mark Cronly, Patrice Behan, Barry Foley, Edward Malone, Liam ReganAbstract:Abstract A rapid confirmatory method has been developed and validated for the simultaneous identification, confirmation and quantitation of 11 nitroimidazoles in eggs by liquid chromatography tandem mass spectrometry (LC–MS/MS). The method is validated in accordance with Commission Decision 2002/657/EC and is capable of analysing metronidazole (MNZ), dimetridazole (DMZ), ronidazole (RNZ), Ipronidazole (IPZ) and their hydroxy metabolites MNZ-OH, HMMNI (hydroxymethyl, methyl nitroimidazole), IPZ-OH. The method is also capable of analysing carnidazole (CRZ), ornidazole (ORZ), tinidazole (TNZ) and ternidazole (TRZ). MNZ, DMZ and RNZ have been assigned a recommended level (RL) of 3 μg kg −1 by the Community Reference Laboratory (CRL) in Berlin. The developed method described in this study is easily able to detect all the nitroimidazole compounds investigated at this level and below. Egg samples are extracted with acetonitrile, and NaCl is added to help remove matrix contaminants. The acetonitrile extract undergoes a liquid–liquid wash step with hexane; it is then evaporated and reconstituted in mobile phase. The reconstituted samples are analysed by liquid chromatography tandem mass spectrometry (LC–MS/MS). The decision limits (CCα) range from 0.33 to 1.26 μg kg −1 and the detection capabilities (CCβ), range from 0.56 to 2.15 μg kg −1 . The results of the inter-assay study, which was performed by fortifying hen egg samples ( n = 18) on three separate days, show the accuracy calculated for the various analytes to range between 87.2 and 106.2%. The precision of the method, expressed as %CV values for the inter-assay variation of each analyte at the three levels of fortification (3, 4.5 and 6.0 μg kg −1 ), ranged between 3.7 and 11.3%. A Day 4 analysis was carried out to examine species variances in eggs from different birds such as duck and quail and investigating differences in various battery and free range hen eggs.
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development and validation of a rapid method for the determination and confirmation of 10 nitroimidazoles in animal plasma using liquid chromatography tandem mass spectrometry
Journal of Chromatography B, 2009Co-Authors: Mark Cronly, Patrice Behan, Barry Foley, Edward Malone, Liam ReganAbstract:A rapid LC-MS/MS method has been developed and validated for the simultaneous identification, confirmation and quantitation of 10 nitroimidazoles in plasma. The method validated in accordance with Commission Decision (CD) 2002/657/EC is capable of analysing for metronidazole (MNZ), dimetridazole (DMZ), ronidazole (RNZ), Ipronidazole (IPZ) and their hydroxy metabolites MNZ-OH, HMMNI (hydroxymethyl, methyl nitroimidazole), IPZ-OH. The method is also capable of analysing carnidazole (CRZ), ornidazole (ORZ) and ternidazole (TRZ) which are rarely analysed by modern methods. MNZ, DMZ and RNZ have a recommended level (RL) of 3 ng mL(-1) which this method is easily able to detect for all the nitroimidazole compounds. Plasma samples are extracted with acetonitrile, and NaCl is added to help remove matrix contaminants. The acetonitrile extract undergoes a liquid-liquid wash step with hexane; it is then evaporated and reconstituted in mobile phase. The reconstituted samples are analysed by liquid chromatography tandem mass spectrometry (LC-MS/MS). The decision limits (CCalpha) range from 0.5 to 1.6 ng mL(-1) and the detection capabilities (CCbeta), range from 0.8 to 2.6 ng mL(-1). The results of the inter-assay study, which was performed by fortifying bovine plasma samples (n=18) on three separate days, show the accuracy calculated for the various analytes range between 101% and 108%. The precision of the method, expressed as CV% values for the inter-assay variation of each analyte at the three levels of fortification (3, 4.5 and 6.0 ng mL(-1)), ranged between 4.9% and 15.2%. A day 4 analysis was carried out to examine species variances in animals such as avian, ovine, porcine and equine.
Mark Cronly - One of the best experts on this subject based on the ideXlab platform.
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development and validation of a rapid multi class method for the confirmation of fourteen prohibited medicinal additives in pig and poultry compound feed by liquid chromatography tandem mass spectrometry
Journal of Pharmaceutical and Biomedical Analysis, 2010Co-Authors: Mark Cronly, Patrice Behan, Barry Foley, Edward Malone, S Earley, M Gallagher, P Shearan, Liam ReganAbstract:A confirmatory method has been developed to allow for the analysis of fourteen prohibited medicinal additives in pig and poultry compound feed. These compounds are prohibited for use as feed additives although some are still authorised for use in medicated feed. Feed samples are extracted by acetonitrile with addition of sodium sulfate. The extracts undergo a hexane wash to aid with sample purification. The extracts are then evaporated to dryness and reconstituted in initial mobile phase. The samples undergo an ultracentrifugation step prior to injection onto the LC-MS/MS system and are analysed in a run time of 26 min. The LC-MS/MS system is run in MRM mode with both positive and negative electrospray ionisation. The method was validated over three days and is capable of quantitatively analysing for metronidazole, dimetridazole, ronidazole, Ipronidazole, chloramphenicol, sulfamethazine, dinitolimide, ethopabate, carbadox and clopidol. The method is also capable of qualitatively analysing for sulfadiazine, tylosin, virginiamycin and avilamycin. A level of 100 microg kg(-1) was used for validation purposes and the method is capable of analysing to this level for all the compounds. Validation criteria of trueness, precision, repeatability and reproducibility along with measurement uncertainty are calculated for all analytes.
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rapid multi class multi residue method for the confirmation of chloramphenicol and eleven nitroimidazoles in milk and honey by liquid chromatography tandem mass spectrometry lc ms
Food Additives and Contaminants Part A-chemistry Analysis Control Exposure & Risk Assessment, 2010Co-Authors: Mark Cronly, Patrice Behan, Barry Foley, Edward Malone, Sheila Martin, Michael P Doyle, Liam ReganAbstract:A confirmatory method was developed to allow for the analysis of eleven nitroimidazoles and also chloramphenicol in milk and honey samples. These compounds are classified as A6 compounds in Annex IV of Council Regulation 2377/90 (European Commission 1990) and therefore prohibited for use in animal husbandry. Milk samples were extracted by acetonitrile with the addition of NaCl; honey samples were first dissolved in water before a similar extraction. Honey extracts underwent a hexane wash to remove impurities. Both milk and honey extracts were evaporated to dryness and reconstituted in initial mobile phase. These were then injected onto a liquid chromatography-tandem mass spectrometry (LC-MS/MS) system and analysed in less than 9 min. The MS/MS was operated in multiple reaction monitoring (MRM) mode with positive and negative electrospray ionization. The method was validated in accordance with Commission Decision 2002/657/EC and is capable of analysing metronidazole, dimetridazole, ronidazole, Ipronidazole...
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rapid confirmatory method for the determination of 11 nitroimidazoles in egg using liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2009Co-Authors: Mark Cronly, Patrice Behan, Barry Foley, Edward Malone, Liam ReganAbstract:Abstract A rapid confirmatory method has been developed and validated for the simultaneous identification, confirmation and quantitation of 11 nitroimidazoles in eggs by liquid chromatography tandem mass spectrometry (LC–MS/MS). The method is validated in accordance with Commission Decision 2002/657/EC and is capable of analysing metronidazole (MNZ), dimetridazole (DMZ), ronidazole (RNZ), Ipronidazole (IPZ) and their hydroxy metabolites MNZ-OH, HMMNI (hydroxymethyl, methyl nitroimidazole), IPZ-OH. The method is also capable of analysing carnidazole (CRZ), ornidazole (ORZ), tinidazole (TNZ) and ternidazole (TRZ). MNZ, DMZ and RNZ have been assigned a recommended level (RL) of 3 μg kg −1 by the Community Reference Laboratory (CRL) in Berlin. The developed method described in this study is easily able to detect all the nitroimidazole compounds investigated at this level and below. Egg samples are extracted with acetonitrile, and NaCl is added to help remove matrix contaminants. The acetonitrile extract undergoes a liquid–liquid wash step with hexane; it is then evaporated and reconstituted in mobile phase. The reconstituted samples are analysed by liquid chromatography tandem mass spectrometry (LC–MS/MS). The decision limits (CCα) range from 0.33 to 1.26 μg kg −1 and the detection capabilities (CCβ), range from 0.56 to 2.15 μg kg −1 . The results of the inter-assay study, which was performed by fortifying hen egg samples ( n = 18) on three separate days, show the accuracy calculated for the various analytes to range between 87.2 and 106.2%. The precision of the method, expressed as %CV values for the inter-assay variation of each analyte at the three levels of fortification (3, 4.5 and 6.0 μg kg −1 ), ranged between 3.7 and 11.3%. A Day 4 analysis was carried out to examine species variances in eggs from different birds such as duck and quail and investigating differences in various battery and free range hen eggs.
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development and validation of a rapid method for the determination and confirmation of 10 nitroimidazoles in animal plasma using liquid chromatography tandem mass spectrometry
Journal of Chromatography B, 2009Co-Authors: Mark Cronly, Patrice Behan, Barry Foley, Edward Malone, Liam ReganAbstract:A rapid LC-MS/MS method has been developed and validated for the simultaneous identification, confirmation and quantitation of 10 nitroimidazoles in plasma. The method validated in accordance with Commission Decision (CD) 2002/657/EC is capable of analysing for metronidazole (MNZ), dimetridazole (DMZ), ronidazole (RNZ), Ipronidazole (IPZ) and their hydroxy metabolites MNZ-OH, HMMNI (hydroxymethyl, methyl nitroimidazole), IPZ-OH. The method is also capable of analysing carnidazole (CRZ), ornidazole (ORZ) and ternidazole (TRZ) which are rarely analysed by modern methods. MNZ, DMZ and RNZ have a recommended level (RL) of 3 ng mL(-1) which this method is easily able to detect for all the nitroimidazole compounds. Plasma samples are extracted with acetonitrile, and NaCl is added to help remove matrix contaminants. The acetonitrile extract undergoes a liquid-liquid wash step with hexane; it is then evaporated and reconstituted in mobile phase. The reconstituted samples are analysed by liquid chromatography tandem mass spectrometry (LC-MS/MS). The decision limits (CCalpha) range from 0.5 to 1.6 ng mL(-1) and the detection capabilities (CCbeta), range from 0.8 to 2.6 ng mL(-1). The results of the inter-assay study, which was performed by fortifying bovine plasma samples (n=18) on three separate days, show the accuracy calculated for the various analytes range between 101% and 108%. The precision of the method, expressed as CV% values for the inter-assay variation of each analyte at the three levels of fortification (3, 4.5 and 6.0 ng mL(-1)), ranged between 4.9% and 15.2%. A day 4 analysis was carried out to examine species variances in animals such as avian, ovine, porcine and equine.
Barry Foley - One of the best experts on this subject based on the ideXlab platform.
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development and validation of a rapid multi class method for the confirmation of fourteen prohibited medicinal additives in pig and poultry compound feed by liquid chromatography tandem mass spectrometry
Journal of Pharmaceutical and Biomedical Analysis, 2010Co-Authors: Mark Cronly, Patrice Behan, Barry Foley, Edward Malone, S Earley, M Gallagher, P Shearan, Liam ReganAbstract:A confirmatory method has been developed to allow for the analysis of fourteen prohibited medicinal additives in pig and poultry compound feed. These compounds are prohibited for use as feed additives although some are still authorised for use in medicated feed. Feed samples are extracted by acetonitrile with addition of sodium sulfate. The extracts undergo a hexane wash to aid with sample purification. The extracts are then evaporated to dryness and reconstituted in initial mobile phase. The samples undergo an ultracentrifugation step prior to injection onto the LC-MS/MS system and are analysed in a run time of 26 min. The LC-MS/MS system is run in MRM mode with both positive and negative electrospray ionisation. The method was validated over three days and is capable of quantitatively analysing for metronidazole, dimetridazole, ronidazole, Ipronidazole, chloramphenicol, sulfamethazine, dinitolimide, ethopabate, carbadox and clopidol. The method is also capable of qualitatively analysing for sulfadiazine, tylosin, virginiamycin and avilamycin. A level of 100 microg kg(-1) was used for validation purposes and the method is capable of analysing to this level for all the compounds. Validation criteria of trueness, precision, repeatability and reproducibility along with measurement uncertainty are calculated for all analytes.
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rapid multi class multi residue method for the confirmation of chloramphenicol and eleven nitroimidazoles in milk and honey by liquid chromatography tandem mass spectrometry lc ms
Food Additives and Contaminants Part A-chemistry Analysis Control Exposure & Risk Assessment, 2010Co-Authors: Mark Cronly, Patrice Behan, Barry Foley, Edward Malone, Sheila Martin, Michael P Doyle, Liam ReganAbstract:A confirmatory method was developed to allow for the analysis of eleven nitroimidazoles and also chloramphenicol in milk and honey samples. These compounds are classified as A6 compounds in Annex IV of Council Regulation 2377/90 (European Commission 1990) and therefore prohibited for use in animal husbandry. Milk samples were extracted by acetonitrile with the addition of NaCl; honey samples were first dissolved in water before a similar extraction. Honey extracts underwent a hexane wash to remove impurities. Both milk and honey extracts were evaporated to dryness and reconstituted in initial mobile phase. These were then injected onto a liquid chromatography-tandem mass spectrometry (LC-MS/MS) system and analysed in less than 9 min. The MS/MS was operated in multiple reaction monitoring (MRM) mode with positive and negative electrospray ionization. The method was validated in accordance with Commission Decision 2002/657/EC and is capable of analysing metronidazole, dimetridazole, ronidazole, Ipronidazole...
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rapid confirmatory method for the determination of 11 nitroimidazoles in egg using liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2009Co-Authors: Mark Cronly, Patrice Behan, Barry Foley, Edward Malone, Liam ReganAbstract:Abstract A rapid confirmatory method has been developed and validated for the simultaneous identification, confirmation and quantitation of 11 nitroimidazoles in eggs by liquid chromatography tandem mass spectrometry (LC–MS/MS). The method is validated in accordance with Commission Decision 2002/657/EC and is capable of analysing metronidazole (MNZ), dimetridazole (DMZ), ronidazole (RNZ), Ipronidazole (IPZ) and their hydroxy metabolites MNZ-OH, HMMNI (hydroxymethyl, methyl nitroimidazole), IPZ-OH. The method is also capable of analysing carnidazole (CRZ), ornidazole (ORZ), tinidazole (TNZ) and ternidazole (TRZ). MNZ, DMZ and RNZ have been assigned a recommended level (RL) of 3 μg kg −1 by the Community Reference Laboratory (CRL) in Berlin. The developed method described in this study is easily able to detect all the nitroimidazole compounds investigated at this level and below. Egg samples are extracted with acetonitrile, and NaCl is added to help remove matrix contaminants. The acetonitrile extract undergoes a liquid–liquid wash step with hexane; it is then evaporated and reconstituted in mobile phase. The reconstituted samples are analysed by liquid chromatography tandem mass spectrometry (LC–MS/MS). The decision limits (CCα) range from 0.33 to 1.26 μg kg −1 and the detection capabilities (CCβ), range from 0.56 to 2.15 μg kg −1 . The results of the inter-assay study, which was performed by fortifying hen egg samples ( n = 18) on three separate days, show the accuracy calculated for the various analytes to range between 87.2 and 106.2%. The precision of the method, expressed as %CV values for the inter-assay variation of each analyte at the three levels of fortification (3, 4.5 and 6.0 μg kg −1 ), ranged between 3.7 and 11.3%. A Day 4 analysis was carried out to examine species variances in eggs from different birds such as duck and quail and investigating differences in various battery and free range hen eggs.
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development and validation of a rapid method for the determination and confirmation of 10 nitroimidazoles in animal plasma using liquid chromatography tandem mass spectrometry
Journal of Chromatography B, 2009Co-Authors: Mark Cronly, Patrice Behan, Barry Foley, Edward Malone, Liam ReganAbstract:A rapid LC-MS/MS method has been developed and validated for the simultaneous identification, confirmation and quantitation of 10 nitroimidazoles in plasma. The method validated in accordance with Commission Decision (CD) 2002/657/EC is capable of analysing for metronidazole (MNZ), dimetridazole (DMZ), ronidazole (RNZ), Ipronidazole (IPZ) and their hydroxy metabolites MNZ-OH, HMMNI (hydroxymethyl, methyl nitroimidazole), IPZ-OH. The method is also capable of analysing carnidazole (CRZ), ornidazole (ORZ) and ternidazole (TRZ) which are rarely analysed by modern methods. MNZ, DMZ and RNZ have a recommended level (RL) of 3 ng mL(-1) which this method is easily able to detect for all the nitroimidazole compounds. Plasma samples are extracted with acetonitrile, and NaCl is added to help remove matrix contaminants. The acetonitrile extract undergoes a liquid-liquid wash step with hexane; it is then evaporated and reconstituted in mobile phase. The reconstituted samples are analysed by liquid chromatography tandem mass spectrometry (LC-MS/MS). The decision limits (CCalpha) range from 0.5 to 1.6 ng mL(-1) and the detection capabilities (CCbeta), range from 0.8 to 2.6 ng mL(-1). The results of the inter-assay study, which was performed by fortifying bovine plasma samples (n=18) on three separate days, show the accuracy calculated for the various analytes range between 101% and 108%. The precision of the method, expressed as CV% values for the inter-assay variation of each analyte at the three levels of fortification (3, 4.5 and 6.0 ng mL(-1)), ranged between 4.9% and 15.2%. A day 4 analysis was carried out to examine species variances in animals such as avian, ovine, porcine and equine.
Edward Malone - One of the best experts on this subject based on the ideXlab platform.
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development and validation of a rapid multi class method for the confirmation of fourteen prohibited medicinal additives in pig and poultry compound feed by liquid chromatography tandem mass spectrometry
Journal of Pharmaceutical and Biomedical Analysis, 2010Co-Authors: Mark Cronly, Patrice Behan, Barry Foley, Edward Malone, S Earley, M Gallagher, P Shearan, Liam ReganAbstract:A confirmatory method has been developed to allow for the analysis of fourteen prohibited medicinal additives in pig and poultry compound feed. These compounds are prohibited for use as feed additives although some are still authorised for use in medicated feed. Feed samples are extracted by acetonitrile with addition of sodium sulfate. The extracts undergo a hexane wash to aid with sample purification. The extracts are then evaporated to dryness and reconstituted in initial mobile phase. The samples undergo an ultracentrifugation step prior to injection onto the LC-MS/MS system and are analysed in a run time of 26 min. The LC-MS/MS system is run in MRM mode with both positive and negative electrospray ionisation. The method was validated over three days and is capable of quantitatively analysing for metronidazole, dimetridazole, ronidazole, Ipronidazole, chloramphenicol, sulfamethazine, dinitolimide, ethopabate, carbadox and clopidol. The method is also capable of qualitatively analysing for sulfadiazine, tylosin, virginiamycin and avilamycin. A level of 100 microg kg(-1) was used for validation purposes and the method is capable of analysing to this level for all the compounds. Validation criteria of trueness, precision, repeatability and reproducibility along with measurement uncertainty are calculated for all analytes.
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rapid multi class multi residue method for the confirmation of chloramphenicol and eleven nitroimidazoles in milk and honey by liquid chromatography tandem mass spectrometry lc ms
Food Additives and Contaminants Part A-chemistry Analysis Control Exposure & Risk Assessment, 2010Co-Authors: Mark Cronly, Patrice Behan, Barry Foley, Edward Malone, Sheila Martin, Michael P Doyle, Liam ReganAbstract:A confirmatory method was developed to allow for the analysis of eleven nitroimidazoles and also chloramphenicol in milk and honey samples. These compounds are classified as A6 compounds in Annex IV of Council Regulation 2377/90 (European Commission 1990) and therefore prohibited for use in animal husbandry. Milk samples were extracted by acetonitrile with the addition of NaCl; honey samples were first dissolved in water before a similar extraction. Honey extracts underwent a hexane wash to remove impurities. Both milk and honey extracts were evaporated to dryness and reconstituted in initial mobile phase. These were then injected onto a liquid chromatography-tandem mass spectrometry (LC-MS/MS) system and analysed in less than 9 min. The MS/MS was operated in multiple reaction monitoring (MRM) mode with positive and negative electrospray ionization. The method was validated in accordance with Commission Decision 2002/657/EC and is capable of analysing metronidazole, dimetridazole, ronidazole, Ipronidazole...
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rapid confirmatory method for the determination of 11 nitroimidazoles in egg using liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2009Co-Authors: Mark Cronly, Patrice Behan, Barry Foley, Edward Malone, Liam ReganAbstract:Abstract A rapid confirmatory method has been developed and validated for the simultaneous identification, confirmation and quantitation of 11 nitroimidazoles in eggs by liquid chromatography tandem mass spectrometry (LC–MS/MS). The method is validated in accordance with Commission Decision 2002/657/EC and is capable of analysing metronidazole (MNZ), dimetridazole (DMZ), ronidazole (RNZ), Ipronidazole (IPZ) and their hydroxy metabolites MNZ-OH, HMMNI (hydroxymethyl, methyl nitroimidazole), IPZ-OH. The method is also capable of analysing carnidazole (CRZ), ornidazole (ORZ), tinidazole (TNZ) and ternidazole (TRZ). MNZ, DMZ and RNZ have been assigned a recommended level (RL) of 3 μg kg −1 by the Community Reference Laboratory (CRL) in Berlin. The developed method described in this study is easily able to detect all the nitroimidazole compounds investigated at this level and below. Egg samples are extracted with acetonitrile, and NaCl is added to help remove matrix contaminants. The acetonitrile extract undergoes a liquid–liquid wash step with hexane; it is then evaporated and reconstituted in mobile phase. The reconstituted samples are analysed by liquid chromatography tandem mass spectrometry (LC–MS/MS). The decision limits (CCα) range from 0.33 to 1.26 μg kg −1 and the detection capabilities (CCβ), range from 0.56 to 2.15 μg kg −1 . The results of the inter-assay study, which was performed by fortifying hen egg samples ( n = 18) on three separate days, show the accuracy calculated for the various analytes to range between 87.2 and 106.2%. The precision of the method, expressed as %CV values for the inter-assay variation of each analyte at the three levels of fortification (3, 4.5 and 6.0 μg kg −1 ), ranged between 3.7 and 11.3%. A Day 4 analysis was carried out to examine species variances in eggs from different birds such as duck and quail and investigating differences in various battery and free range hen eggs.
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development and validation of a rapid method for the determination and confirmation of 10 nitroimidazoles in animal plasma using liquid chromatography tandem mass spectrometry
Journal of Chromatography B, 2009Co-Authors: Mark Cronly, Patrice Behan, Barry Foley, Edward Malone, Liam ReganAbstract:A rapid LC-MS/MS method has been developed and validated for the simultaneous identification, confirmation and quantitation of 10 nitroimidazoles in plasma. The method validated in accordance with Commission Decision (CD) 2002/657/EC is capable of analysing for metronidazole (MNZ), dimetridazole (DMZ), ronidazole (RNZ), Ipronidazole (IPZ) and their hydroxy metabolites MNZ-OH, HMMNI (hydroxymethyl, methyl nitroimidazole), IPZ-OH. The method is also capable of analysing carnidazole (CRZ), ornidazole (ORZ) and ternidazole (TRZ) which are rarely analysed by modern methods. MNZ, DMZ and RNZ have a recommended level (RL) of 3 ng mL(-1) which this method is easily able to detect for all the nitroimidazole compounds. Plasma samples are extracted with acetonitrile, and NaCl is added to help remove matrix contaminants. The acetonitrile extract undergoes a liquid-liquid wash step with hexane; it is then evaporated and reconstituted in mobile phase. The reconstituted samples are analysed by liquid chromatography tandem mass spectrometry (LC-MS/MS). The decision limits (CCalpha) range from 0.5 to 1.6 ng mL(-1) and the detection capabilities (CCbeta), range from 0.8 to 2.6 ng mL(-1). The results of the inter-assay study, which was performed by fortifying bovine plasma samples (n=18) on three separate days, show the accuracy calculated for the various analytes range between 101% and 108%. The precision of the method, expressed as CV% values for the inter-assay variation of each analyte at the three levels of fortification (3, 4.5 and 6.0 ng mL(-1)), ranged between 4.9% and 15.2%. A day 4 analysis was carried out to examine species variances in animals such as avian, ovine, porcine and equine.
Patrice Behan - One of the best experts on this subject based on the ideXlab platform.
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development and validation of a rapid multi class method for the confirmation of fourteen prohibited medicinal additives in pig and poultry compound feed by liquid chromatography tandem mass spectrometry
Journal of Pharmaceutical and Biomedical Analysis, 2010Co-Authors: Mark Cronly, Patrice Behan, Barry Foley, Edward Malone, S Earley, M Gallagher, P Shearan, Liam ReganAbstract:A confirmatory method has been developed to allow for the analysis of fourteen prohibited medicinal additives in pig and poultry compound feed. These compounds are prohibited for use as feed additives although some are still authorised for use in medicated feed. Feed samples are extracted by acetonitrile with addition of sodium sulfate. The extracts undergo a hexane wash to aid with sample purification. The extracts are then evaporated to dryness and reconstituted in initial mobile phase. The samples undergo an ultracentrifugation step prior to injection onto the LC-MS/MS system and are analysed in a run time of 26 min. The LC-MS/MS system is run in MRM mode with both positive and negative electrospray ionisation. The method was validated over three days and is capable of quantitatively analysing for metronidazole, dimetridazole, ronidazole, Ipronidazole, chloramphenicol, sulfamethazine, dinitolimide, ethopabate, carbadox and clopidol. The method is also capable of qualitatively analysing for sulfadiazine, tylosin, virginiamycin and avilamycin. A level of 100 microg kg(-1) was used for validation purposes and the method is capable of analysing to this level for all the compounds. Validation criteria of trueness, precision, repeatability and reproducibility along with measurement uncertainty are calculated for all analytes.
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rapid multi class multi residue method for the confirmation of chloramphenicol and eleven nitroimidazoles in milk and honey by liquid chromatography tandem mass spectrometry lc ms
Food Additives and Contaminants Part A-chemistry Analysis Control Exposure & Risk Assessment, 2010Co-Authors: Mark Cronly, Patrice Behan, Barry Foley, Edward Malone, Sheila Martin, Michael P Doyle, Liam ReganAbstract:A confirmatory method was developed to allow for the analysis of eleven nitroimidazoles and also chloramphenicol in milk and honey samples. These compounds are classified as A6 compounds in Annex IV of Council Regulation 2377/90 (European Commission 1990) and therefore prohibited for use in animal husbandry. Milk samples were extracted by acetonitrile with the addition of NaCl; honey samples were first dissolved in water before a similar extraction. Honey extracts underwent a hexane wash to remove impurities. Both milk and honey extracts were evaporated to dryness and reconstituted in initial mobile phase. These were then injected onto a liquid chromatography-tandem mass spectrometry (LC-MS/MS) system and analysed in less than 9 min. The MS/MS was operated in multiple reaction monitoring (MRM) mode with positive and negative electrospray ionization. The method was validated in accordance with Commission Decision 2002/657/EC and is capable of analysing metronidazole, dimetridazole, ronidazole, Ipronidazole...
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rapid confirmatory method for the determination of 11 nitroimidazoles in egg using liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2009Co-Authors: Mark Cronly, Patrice Behan, Barry Foley, Edward Malone, Liam ReganAbstract:Abstract A rapid confirmatory method has been developed and validated for the simultaneous identification, confirmation and quantitation of 11 nitroimidazoles in eggs by liquid chromatography tandem mass spectrometry (LC–MS/MS). The method is validated in accordance with Commission Decision 2002/657/EC and is capable of analysing metronidazole (MNZ), dimetridazole (DMZ), ronidazole (RNZ), Ipronidazole (IPZ) and their hydroxy metabolites MNZ-OH, HMMNI (hydroxymethyl, methyl nitroimidazole), IPZ-OH. The method is also capable of analysing carnidazole (CRZ), ornidazole (ORZ), tinidazole (TNZ) and ternidazole (TRZ). MNZ, DMZ and RNZ have been assigned a recommended level (RL) of 3 μg kg −1 by the Community Reference Laboratory (CRL) in Berlin. The developed method described in this study is easily able to detect all the nitroimidazole compounds investigated at this level and below. Egg samples are extracted with acetonitrile, and NaCl is added to help remove matrix contaminants. The acetonitrile extract undergoes a liquid–liquid wash step with hexane; it is then evaporated and reconstituted in mobile phase. The reconstituted samples are analysed by liquid chromatography tandem mass spectrometry (LC–MS/MS). The decision limits (CCα) range from 0.33 to 1.26 μg kg −1 and the detection capabilities (CCβ), range from 0.56 to 2.15 μg kg −1 . The results of the inter-assay study, which was performed by fortifying hen egg samples ( n = 18) on three separate days, show the accuracy calculated for the various analytes to range between 87.2 and 106.2%. The precision of the method, expressed as %CV values for the inter-assay variation of each analyte at the three levels of fortification (3, 4.5 and 6.0 μg kg −1 ), ranged between 3.7 and 11.3%. A Day 4 analysis was carried out to examine species variances in eggs from different birds such as duck and quail and investigating differences in various battery and free range hen eggs.
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development and validation of a rapid method for the determination and confirmation of 10 nitroimidazoles in animal plasma using liquid chromatography tandem mass spectrometry
Journal of Chromatography B, 2009Co-Authors: Mark Cronly, Patrice Behan, Barry Foley, Edward Malone, Liam ReganAbstract:A rapid LC-MS/MS method has been developed and validated for the simultaneous identification, confirmation and quantitation of 10 nitroimidazoles in plasma. The method validated in accordance with Commission Decision (CD) 2002/657/EC is capable of analysing for metronidazole (MNZ), dimetridazole (DMZ), ronidazole (RNZ), Ipronidazole (IPZ) and their hydroxy metabolites MNZ-OH, HMMNI (hydroxymethyl, methyl nitroimidazole), IPZ-OH. The method is also capable of analysing carnidazole (CRZ), ornidazole (ORZ) and ternidazole (TRZ) which are rarely analysed by modern methods. MNZ, DMZ and RNZ have a recommended level (RL) of 3 ng mL(-1) which this method is easily able to detect for all the nitroimidazole compounds. Plasma samples are extracted with acetonitrile, and NaCl is added to help remove matrix contaminants. The acetonitrile extract undergoes a liquid-liquid wash step with hexane; it is then evaporated and reconstituted in mobile phase. The reconstituted samples are analysed by liquid chromatography tandem mass spectrometry (LC-MS/MS). The decision limits (CCalpha) range from 0.5 to 1.6 ng mL(-1) and the detection capabilities (CCbeta), range from 0.8 to 2.6 ng mL(-1). The results of the inter-assay study, which was performed by fortifying bovine plasma samples (n=18) on three separate days, show the accuracy calculated for the various analytes range between 101% and 108%. The precision of the method, expressed as CV% values for the inter-assay variation of each analyte at the three levels of fortification (3, 4.5 and 6.0 ng mL(-1)), ranged between 4.9% and 15.2%. A day 4 analysis was carried out to examine species variances in animals such as avian, ovine, porcine and equine.
