RESUMO
Ractopamine (RAC), is a ß-adrenergic agonist increasingly used in the swine and cattle industry. This compound redirects nutrients to favour leanness rather than fat deposition, improves growth and carcass traits gaining higher economic benefit to producers. Countries around the world are split over whether to allow the use of RAC in meat production. Clenbuterol (CLB) and salbutamol (SLB) are anillinic and phenolic ß-agonists, respectively, with the same capacity of producing economic benefits for the meat sector. However, they are prohibited because of the potentially adverse reactions they can cause in consumers. The three ß-agonist compounds have been included in the Brazilian National Regulatory Survey and consequentially there is an eminent need for reliable methods capable of detecting those substances at the same time and reduce analytical costs. Therefore, an LC-MS/MS method for the simultaneous determination of residual RAC, CLB and SAL in swine and cattle muscle was developed and validated with quantification levels respecting the action levels established for Brazil which are 0.1, 0.2 and 5 µg kg-1 for RAC, CLB and SAL, respectively. Samples were quantified using RAC-d5, CLB-d9 and SLB-d6 as internal standards. The validation was performed according to European Union Decision 2002/657, which includes criteria (CCα, CCß, recovery, repeatability, reproducibility and calibration curve). The method meets the Brazilian regulatory requirement that establishes criteria and procedures for the determination of parameters such as CCα, CCß, precision and recovery. CCα values were 0.02, 0.21 and 5.42 µg kg-1 for RAC, CLB and SAL, respectively, in bovine and swine muscle samples; CCß values were 0.03, 0.22 and 5.8 µg kg-1 for RAC, CLB and SAL, respectively, in bovine and swine muscle samples. Average recoveries fortified with 0.05-7.5 µg kg-1 of the studied ß-agonist leads around 95%. The method was demonstrated to be suitable for the determination of RAC, CLB and SLB in swine and cattle muscle samples.
Assuntos
Albuterol/análise , Clembuterol/análise , Músculos/química , Fenetilaminas/análise , Animais , Brasil , Bovinos , Cromatografia Líquida de Alta Pressão , Laboratórios , Limite de Detecção , Suínos , Espectrometria de Massas em TandemRESUMO
Nitroimidazoles are a class of veterinary drugs used for the treatment and prevention of certain bacterial and protozoal diseases in poultry, swine dysentery and genital trichomoniasis in cattle. Since the safety assessment of nitroimidazoles showed them to be genotoxic, carcinogenic and mutagenic, a number of nitroimidazoles have been banned for therapeutic purposes in different countries. Moreover, nitroimidazoles have also been extensively used as growth promoters in food-producing animals. Due to their efficacious improvement in meat production and feed conversion, deliberate use still exists. Therefore, the illegal use of nitroimidazoles in animal husbandry must be monitored. A sensitive method based on LC-MS/MS for the simultaneous determination and confirmation of five banned nitroimidazole drugs including metronidazole, ronidazole, dimetridazole, metronidazole-OH (metabolite of metronidazole), and 2-hydroxymethyl-1-methyl-5-nitroimidazole (metabolite of ronidazole and dimetridazole) in bovine muscle, using ronidazole-d3 as an internal standard, was developed and validated. After extraction with ethyl acetate and evaporation, the nitroimidazoles were reconstituted in petroleum ether and purified, and LC-MS/MS analysis was performed. The method was validated according to Brazilian Regulation 24/2009 (equivalent to European Union Decision 2002/657/EC). Parameters such as decision limit (CCα), detection capability (CCß), precision, accuracy, uncertaincy and ruggedness were determined. Average accuracy of the five nitroimidazoles from bovine muscle fortified at 5 levels (0.5, 1.0, 1.5, 2.0 and 2.5 µg kg(-1)) ranged from 96% to 103%. The calculated CCα ranged from 0.0 to 0.17 µg kg(-1); CCß ranged from 0.08 to 0.41 µg kg(-1). A complete statistical analysis was performed and the results indicate that the method is robust when subjected to day-to-day analytical variations.
Assuntos
Anti-Infecciosos/análise , Cromatografia Líquida/métodos , Resíduos de Drogas/análise , Músculos/química , Espectrometria de Massas em Tandem/métodos , Animais , Bovinos , Limite de Detecção , Padrões de Referência , Reprodutibilidade dos TestesRESUMO
Florfenicol, a derivative of thiamphenicol in which the hydroxyl group at C-3 has been replaced with fluorine, is listed by the World Health Organization as an antibacterial agent for human medicine that is critically important in risk management strategies for non-human use. AOAC International has also identified it as an important molecule for the development of effective methods for the seafood sector. Following inspection missions from the European Union and United States of America, it was introduced in the Brazilian Residues Control Program to fulfill export and internal national requirements with a Maximum Residue Limit of 800 µg/kg. A high performance liquid chromatography method with ultraviolet detection at a wavelength of 230 nm (λ = 230 nm) for the detection of florfenicol in fish muscle was developed and validated according to the Brazilian Regulation 24/2009 (equivalent to European Union Decision 2002/657/EC). Fish samples were extracted with ethyl acetate and hexane followed by C18 solid phase clean-up and chromatographic separation on a reversed-phase C18 LC column with acetonitrile:water as mobile phase. The method results were also was compared with those obtained using liquid chromatography-tandem quadrupole mass spectrometry. The method meets the Brazilian regulatory requirements with a decision limit (CCα) of 840 µg/kg and detection capability (CCß) of 879 µg/kg. This method is easy to use and has been implemented into Brazil's residue control program, with liquid chromatography-tandem mass spectrometry (LC-MS/MS) confirmation of any suspect samples using the same method.
Assuntos
Antibacterianos/análise , Resíduos de Drogas/análise , Peixes/metabolismo , Alimentos Marinhos/análise , Espectrometria de Massas em Tandem/métodos , Tianfenicol/análogos & derivados , Animais , Antibacterianos/isolamento & purificação , Brasil , Cromatografia Líquida/métodos , Resíduos de Drogas/isolamento & purificação , Músculos/metabolismo , Reprodutibilidade dos Testes , Extração em Fase Sólida/métodos , Tianfenicol/análise , Tianfenicol/isolamento & purificaçãoRESUMO
Streptomycin is an aminoglycoside antibiotic used in apiculture to protect bees against a variety of brood diseases. Brazilian authorities have included it in the National Regulatory Monitoring Program for honey production. A simple and reliable method using liquid chromatography-tandem mass spectrometry has been developed and validated for the determination of streptomycin in honey. The chromatography separation was performed on a Gemini 5 microm C18 (50 mm x 2 mm) column using 5mM heptafluorbutiric acid/acetonitrile (85:15) as the mobile phase at a flow rate of 0.2 mLmin(-1). The detection of the analyte was achieved by positive ionization electrospray in multiple reaction-monitoring modes. Two characteristic transitions were monitored for streptomycin. Some analytical parameters were validated according to the guidelines laid down by European Commission Decision 2002/657/EC: decision limit, detection capability, recovery, precision and ruggedness. The recoveries of streptomycin from honey fortified at 2.5, 10, 15 and 20 microgkg(-1) levels are around 100%. The decision limit and detection capability of streptomycin was 3 microgkg(-1) and 4.7 microgkg(-1) respectively.
Assuntos
Antibacterianos/análise , Cromatografia Líquida de Alta Pressão/métodos , Resíduos de Drogas/análise , Mel/análise , Estreptomicina/análise , Espectrometria de Massas em Tandem/métodos , Antibacterianos/isolamento & purificação , Resíduos de Drogas/isolamento & purificação , Reprodutibilidade dos Testes , Estreptomicina/isolamento & purificaçãoRESUMO
The sulfonamides are stable chemotherapeutics used against the bacterial disease affecting bees, known as American foulbrood (Bacillus larvae), so their residues could appear in the honey of treated bees. Their presence at a concentration above the limit value is a potential hazard to human health. Brazilian authorities have included in the National regulatory monitoring program, the control of the three most widely used sulfonamides in honey production, i.e., sulfathiazole, sulfamethazine and sulfadimethoxine. A method for the determination of residual sulfonamides in honey, using sulfapyridine as an internal standard has been developed, optimized and validated. Some changes were implemented on current available methodologies for the analysis of sulfonamides in honey in order to adopt such procedures to Brazilian honey samples. Sulfonamides were extracted from honey with dichloromethane after dissolution with 30% sodium chloride, and cleaned up with solid phase extraction on Florisil columns. The eluate was analyzed by high-performance liquid chromatography with ultraviolet detection. The limit of detection was determined at 3 microg kg(-1), 4 microg kg(-1) and 5 microg kg(-1) for sulfathiazole, sulfamethazine and sulfadimethoxine, respectively with average recoveries of 61.0% for sulfathiazole; 94.5% for sulfamethazine and 86.0% for sulfadimethoxine at the 100 microg kg(-1) level. As the final step of validation procedure, the analysts were submitted to a blind spiked sample prepared by the quality assurance officer which results were successfully obtained regarding recovery and deviations.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Mel/análise , Sulfonamidas/análise , Raios Ultravioleta , Carboidratos/química , Cromatografia Líquida de Alta Pressão/normas , Hidrólise , Cloreto de Metileno/química , Reprodutibilidade dos Testes , Cloreto de Sódio/química , Extração em Fase Sólida , Sulfatiazol , Sulfatiazóis/químicaRESUMO
Ethopabate is frequently used in the prophylaxis and treatment of coccidiosis in poultry. Residues of this drug in food present a potential risk to consumers. A simple, rapid, and sensitive column high-performance liquid chromatographic (HPLC) method with UV detection for determination of ethopabate in poultry liver is presented. The drug is extracted with acetonitrile. After evaporation, the residue is dissolved with an acetone-hexane mixture and cleaned up by solid-phase extraction using Florisil columns. The analyte is then eluted with methanol. LC analysis is carried out on a C18 5 microm Gemini column, 15 cm x 4.6 mm. Ethopabate is quantified by means of UV detection at 270 nm. Parameters such as decision limit, detection capability, precision, recovery, ruggedness, and measurement uncertainty were calculated according to method validation guidelines provided in 2002/657/EC and ISO/IEC 17025:2005. Decision limit and detection capability were determined to be 2 and 3 microg/kg, respectively. Average recoveries from poultry samples fortified with 10, 15, and 20 microg/kg levels of ethopabate were 100-105%. A complete statistical analysis was performed on the results obtained, including an estimation of the method uncertainty. The method is to be implemented into Brazil's residue monitoring and control program for ethopabate.