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1.
J Sep Sci ; 40(3): 671-676, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27935246

RESUMO

An analytical method has been developed for the detection of a metabolite of nifursol, 3,5-dinitrosalicylic acid hydrazide, in foodstuffs of animal origin (chicken liver, pork liver, lobster, shrimp, eel, sausage, and honey). The method combines liquid chromatography and tandem mass spectrometry with liquid-liquid extraction. Samples were hydrolyzed with hydrochloric acid and derivatized with 2-nitrobenzaldehyde at 37°C for 16 h. The solutions of derivatives were adjusted to pH 7.0-7.5, and the metabolite was extracted with ethyl acetate. 3,5-Dinitrosalicylic acid hydrazide determination was performed in the negative electrospray ionization method. Both isotope-labeled internal standard and matrix-matched calibration solutions were used to correct the matrix effects. Limits of quantification were 0.5 µg/kg for all samples. The average recoveries, measured at three concentration levels (0.5, 2.0, and 10 µg/kg) were in the range of 75.8-108.4% with relative standard deviations below 9.8%. The developed method exhibits a high sensitivity and selectivity for the routine determination and confirmation of the presence of a metabolite of nifursol in foodstuffs of animal origin.


Assuntos
Cromatografia Líquida , Análise de Alimentos/métodos , Extração Líquido-Líquido , Produtos da Carne/análise , Carne/análise , Nitrofuranos/análise , Espectrometria de Massas em Tandem , Animais , Limite de Detecção , Nitrofuranos/química , Suínos
2.
J Agric Food Chem ; 62(45): 10881-8, 2014 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-25338226

RESUMO

Increasing attention has been focused on the artificial flavorings added in foods, especially those for infants and children. For the first time, a sensitive and efficient analytical method based on gas chromatography-tandem mass spectrometry (GC-MS/MS) was developed for the simultaneous identification and quantification of four flavoring agents (vanillin, methylvanillin, ethylvanillin, and coumarin) in infant formula samples. The flavorings in samples were extracted with methanol/water (v/v, 1:1), cleaned up by solid-phase extraction, and determined by GC-MS/MS in selected reaction monitoring (SRM) mode. Both isotope-labeled internal standards and matrix-matched calibration solutions were used to correct the matrix effects. The limit of quantification (LOQ) was calculated as 10 times the standard deviation, and it was 10.0 µg kg (-1) for vanillin, methylvanillin, ethylvanillin, and coumarin. The average recoveries were in the range of 82.8-107.5% with relative standard deviations (RSDs) below 8.9% measured at three concentration levels (10, 50, and 100 µg kg(-1)). The proposed method is suitable for the sensitive and accurate simultaneous determination of four flavoring agents in infant formula samples and also provided potential use for reference in terms of real analysis of other foods.


Assuntos
Aromatizantes/química , Aromatizantes/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Fórmulas Infantis/química , Extração em Fase Sólida/métodos , Benzaldeídos/química , Benzaldeídos/isolamento & purificação , Cumarínicos/química , Cumarínicos/isolamento & purificação , Humanos , Estrutura Molecular
3.
J Dairy Sci ; 97(2): 679-86, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24359823

RESUMO

A simple, precise, accurate, and validated liquid chromatography-quadrupole linear ion trap mass spectrometry method was developed for the determination of vanillin, ethyl vanillin, and coumarin in infant formula samples. Following ultrasonic extraction with methanol/water (1:1, vol/vol), and clean-up on an HLB solid-phase extraction cartridge (Waters Corp., Milford, MA), samples were separated on a Waters XSelect HSS T3 column (150 × 2.1-mm i.d., 5-µm film thickness; Waters Corp.), with 0.1% formic acid solution-acetonitrile as mobile phase at a flow rate of 0.25 mL/min. Quantification of the target was performed by the internal standard approach, using isotopically labeled compounds for each chemical group, to correct matrix effects. Data acquisition was carried out in multiple reaction monitoring transitions mode, monitoring 2 multiple reaction monitoring transitions to ensure an accurate identification of target compounds in the samples. Additional identification and confirmation of target compounds were performed using the enhanced product ion modus of the linear ion trap. The novel liquid chromatography-quadrupole linear ion trap mass spectrometry platform offers the best sensitivity and specificity for characterization and quantitative determination of vanillin, ethyl vanillin, and coumarin in infant formula and fulfills the quality criteria for routine laboratory application.


Assuntos
Carcinógenos/análise , Cromatografia Líquida/métodos , Aromatizantes/análise , Contaminação de Alimentos/análise , Fórmulas Infantis/química , Espectrometria de Massas/métodos , Benzaldeídos/análise , Cumarínicos/análise , Humanos , Lactente , Recém-Nascido
4.
J Dairy Sci ; 96(11): 6877-6882, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24054295

RESUMO

A simple, precise, accurate, and validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the determination of dicyandiamide residue in infant formula samples. Following microwave-assisted extraction with 5% formic acid and clean-up on a Sep-Pak AC-2 SPE cartridge, samples were separated on a ZIC-HILIC HPLC column (150 × 2.1mm i.d., 5-µm film thickness; Merck KGaA, Darmstadt, Germany) with 20mM ammonium acetate solution-acetonitrile as mobile phase at a flow rate of 0.25 mL/min. A linear calibration curve was obtained in the concentration range from 1.0 to 50 ng/mL. Infant formula samples were fortified with dicyandiamide at 3 levels, producing average recovery yields of 83.6 to 95.7%. The limits of detection and quantification of dicyandiamide were 3 and 10 µg/kg, respectively. Due to its simplicity and accuracy, the straightforward method is particularly suitable for routine dicyandiamide detection.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Resíduos de Drogas/isolamento & purificação , Contaminação de Alimentos/análise , Guanidinas/análise , Fórmulas Infantis/química , Espectrometria de Massas em Tandem/métodos , Animais , Calibragem , Resíduos de Drogas/análise , Guanidinas/química , Guanidinas/isolamento & purificação , Humanos , Lactente , Micro-Ondas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Extração em Fase Sólida
5.
J Sep Sci ; 36(5): 857-62, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23378155

RESUMO

A new method based on pressurized liquid extraction followed by LC-MS/MS analysis has been developed for the identification and quantification of three capsaicinoids (capsaicin, dihydrocapsaicin, and nordihydrocapsaicin) in extracts of Capsicum annuum. For the recovery of three capsaicinoids, the efficiency levels of ultrasonic-assisted extraction, microwave-assisted extraction, Soxhlet extraction, and pressurized liquid extraction were compared under different conditions. Pressurized liquid extraction resulted in higher yields. Pressurized liquid extractions were performed using methanol; temperature was set at 100°C and pressure at 1500 psi. LC analysis was performed on a Waters XBridge™ C18 column (150 × 2.1 mm, id 3.5 µm) eluted by a mobile phase of 0.1% formic acid and ACN. Data acquisition was carried out in multiple reaction monitoring transitions mode, monitoring two-reaction monitoring transitions to ensure an accurate identification of target compounds in the samples. The proposed method is rapid, simple, and could be utilized for the routine analysis of three capsaicinoids in C. annuum samples.


Assuntos
Capsaicina/análise , Capsaicina/isolamento & purificação , Capsicum/química , Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais/análise , Extratos Vegetais/isolamento & purificação , Espectrometria de Massas em Tandem/métodos , Capsaicina/análogos & derivados
6.
J Food Sci ; 77(12): C1269-72, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23171446

RESUMO

A fast, simple, low cost, and high-throughput method has been developed for the determination of citrus red 2 dye in orange and orange juice samples. The procedure is based on microwave-assisted extraction followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The method was optimized, and the analyte was efficiently extracted from the samples in 30 min using hexane/acetone (v/v, 3 : 1). The method was validated and showed good linearity and selectivity. The limits of quantification (LOQs) were 5 µg/kg (sample size of 2 g) for both orange and orange juice samples. The average recoveries, measured at 3 concentration levels (5, 10, and 20 µg/kg), were in the range 77.5% to 87.6% for the compound tested with relative standard deviations below 7.3%. The proposed method is rapid, accurate, and could be utilized for the routine analysis of citrus red 2 dye in orange and orange juice samples.


Assuntos
Bebidas/análise , Cromatografia Líquida/métodos , Citrus sinensis/química , Cicloexanos/análise , Manipulação de Alimentos/métodos , Indóis/análise , Espectrometria de Massas em Tandem/métodos , Micro-Ondas , Reprodutibilidade dos Testes , Extração em Fase Sólida
7.
Se Pu ; 29(2): 176-9, 2011 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-21598521

RESUMO

A method for the analysis of 4 alkaloids in Corydalis decumbens (Thunb.) Pers. was developed by high performance liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-MS/MS). The sample was extracted in methanol by ultrasonic, filtered and diluted with methanol for further analysis. The analysis was performed on a C18 column (150 mm x 2.1 mm, 3.5 microm) using a gradient elution program with the mobile phase of 0.2% acetic acid solution and acetonitrile. The analyte was determined by an electrospray ionization tandem mass spectrometry in multiple reactions monitoring (MRM) mode. The qualitative and quantitative analyses were based on the retention times and characteristic ion pairs consisting of one parent ion and two fragment ions of the analyte. The limits of detection (LODs) for 4 alkaloids were in the range of 0.02 - 0.2 microg/L, and the limits of quantification (LOQs) were in the range of 0.07 - 0.66 microg/L. The average recoveries were in the range of 93.6% - 103.5% for 4 alkaloids with the relative standard deviations below 3.8%. This method is reliable, sensitive and reproducible, and it can be used for the quality control of Corydalis decumbens (Thunb.) Pers. sample.


Assuntos
Alcaloides/análise , Cromatografia Líquida de Alta Pressão/métodos , Corydalis/química , Medicamentos de Ervas Chinesas/química , Espectrometria de Massas em Tandem/métodos , Benzofenantridinas/análise , Alcaloides de Berberina/análise , Bicuculina/análise
8.
Talanta ; 84(4): 1026-31, 2011 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-21530775

RESUMO

A new method based on pressurised liquid extraction (PLE) followed by liquid chromatography-triple quadrupole linear ion trap mass spectrometry (LC-QTrap-MS) analysis has been developed for the identification and quantification of four major alkaloids in extracts of Corydalis decumbens (Thunb.) Pers. PLE extractions were performed using 90% ethanol; temperature was set at 100°C and pressure at 1500 psi. HPLC analysis was performed on a Waters XBridge™ C(18) column (150 mm × 2.1mm i.d., 3.5 µm) eluted by a mobile phase of acetonitrile and 0.2% acetic acid. Data acquisition was carried out in multiple reaction monitoring transitions (MRMs) mode, monitoring two MRM transitions to ensure an accurate identification of target compounds in the samples. Additional identification and confirmation of target compounds were performed using the enhanced product ion modus (EPI) of the linear ion trap. The novel LC-QTrap-MS platform offers the best sensitivity and specificity for characterization and quantitative determination of the four alkaloids in C. decumbens (Thunb.) Pers. and fulfils the quality criteria for routine laboratory application.


Assuntos
Alcaloides/análise , Alcaloides/isolamento & purificação , Fracionamento Químico/métodos , Cromatografia Líquida/métodos , Corydalis/química , Espectrometria de Massas/métodos , Pressão , Alcaloides/metabolismo , Limite de Detecção , Modelos Lineares , Extratos Vegetais/química , Reprodutibilidade dos Testes , Sonicação , Espectrometria de Massas em Tandem , Fatores de Tempo
9.
J Sep Sci ; 34(4): 371-5, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21298779

RESUMO

Cyanuric acid (CYA) is attracting more attention due to its potential toxicity. In the present work, microwave-assisted extraction method in combination with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was proposed for the determination of CYA in pet food samples. Among different solvents, diethylamine-acetonitrile-water mixture (1:5:4, v/v) was found to be the best one as the extractant due to the strong polarity of CYA in the pet food. An internal standard, (13) C(3) -labeled CYA, was used in the extractions. The separation was performed on a MERCK ZIC HILIC column (150 mm × 2.1 mm id, 5 µm) with gradient elution of 20 mM ammonium acetate solution-acetonitrile. CYA was well retained (Rt = 5.10 min) and eluted with good peak shape. The method could respond linearly with CYA at concentrations from 1.0 to 50 ng/mL with a quantification limit of 0.25 mg/kg. The intra- and inter-day precision was less than 4.0% and the recovery of the assay was in the range of 90.4-108.1%. In the analysis of practical spiked pet food samples, the new method yielded satisfactory results. Due to its simplicity and accuracy the straightforward method is particularly suitable for routine CYA detection.


Assuntos
Ração Animal/análise , Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão/métodos , Resíduos de Drogas/análise , Resíduos de Drogas/isolamento & purificação , Contaminação de Alimentos/análise , Espectrometria de Massas em Tandem/métodos , Triazinas/análise , Triazinas/isolamento & purificação , Cromatografia Líquida de Alta Pressão/veterinária , Micro-Ondas , Espectrometria de Massas em Tandem/veterinária
10.
Food Chem ; 127(2): 875-9, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23140748

RESUMO

In the present work, microwave-assisted extraction method in combining with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was proposed for the determination of cyanuric acid (CYA) in infant formula samples. The separation was performed on a MERCK ZIC HILIC column (150×2.1mm i.d., 5µm) with gradient elution of 20mM ammonium acetate solution - acetonitrile. The method could respond linearly with cyanuric acid at concentrations from 1.0 to 50ngmL(-1) with a quantification limit of 0.25mgkg(-1). The intra- and inter-day precision was less than 4% and the recovery of the assay was in the range of 86.7-93.1%. In the analysis of practical spiked infant formula samples, the new method yielded satisfactory results. Due to its simplicity and accuracy the straightforward method is particularly suitable for routine cyanuric acid detection.

11.
J Sep Sci ; 33(21): 3319-25, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20878658

RESUMO

The concentrations of hexabromocyclododecanes (HBCD) in Sargassum fusiforme, the common Chinese edible seaweed, were investigated by LC-MS/MS. For the recovery of HBCD, the efficiency levels of ultrasonic-assisted extraction, microwave-assisted extraction, Soxhlet extraction and pressurised liquid extraction were compared under different conditions. Pressurised liquid extraction and ultrasonic-assisted extraction resulted in complete extraction of HBCD (92.7-102.5% recovery). Microwave-assisted extraction and Soxhlet extraction, on the other hand, offered relatively low extraction recoveries (82.1-90.6%). The instrumental LODs on columns in this study were 1.0, 0.3 and 0.7 ng/g for α-HBCD, ß-HBCD and γ-HBCD, respectively. Because of its accuracy, this straightforward method is particularly suitable for routine HBCD analysis.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Hidrocarbonetos Bromados/análise , Micro-Ondas , Sargassum/química , Ultrassom , Poluentes Químicos da Água/análise , Humanos , Estrutura Molecular , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Solventes/química , Estereoisomerismo
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