Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
J Anal Toxicol ; 46(8): 918-924, 2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-35953454

RESUMO

Although kombucha is a popular fermented beverage, the presence of alcohol markers has not been well studied despite being potential indicators of unintentional impairment. Ethyl glucuronide (EtG) and ethyl sulfate (EtS) were measured in oral fluid and urine collected after consumption of regular or hard kombucha. Participants drank within 20 min and provided all urine voids for 12 h, the first urine voids on days 2 and 3 and oral fluid specimens at fixed time points for 48 h. Screening employed liquid chromatography-tandem mass spectrometry (LC-MS-MS; EtS, 25 ng/mL cutoff [oral]; 100 ng/mL cutoff [urine]; EtG, 500 ng/mL cutoff [urine] and immunoassay (IA; EtG, 500 ng/mL cutoff [urine]). After consuming regular kombucha (n = 12 participants), EtS was not detected in oral fluid but both markers were detected by LC-MS-MS in urine specimens within the first five voids from 83% of participants with median (range) concentrations of 240 (100-3,700) ng/mL for EtS and 830 (530-2,200) ng/mL for EtG. Neither marker was positive by IA nor LC-MS-MS after day 1. After consuming hard kombucha (n = 7 participants), 2 (2.8%) of the 70 collected oral fluid specimens tested positive for EtS 3 h after consumption; however, 21 (30%) had EtS levels above the limit of detection (LOD, 10 ng/mL) after 0.5-8 h. Both markers were detected in urine specimens from all participants with median (range) concentrations of 3,381 (559-70,250) ng/mL for EtS and 763 (104-12,864) ng/mL For EtG. Urine specimens were negative for EtG and EtS by the end of the 48-hour study.


Assuntos
Glucuronatos , Ésteres do Ácido Sulfúrico , Consumo de Bebidas Alcoólicas/urina , Biomarcadores/urina , Etanol/urina , Glucuronatos/urina , Humanos , Ésteres do Ácido Sulfúrico/urina
2.
Methods Mol Biol ; 1872: 67-73, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30350280

RESUMO

High-performance liquid chromatography tandem mass spectrometry (LC-MS/MS) has become a primary analytical methodology in therapeutic drug monitoring of antiepileptic drugs (AEDs). To demonstrate the utility of LC-MS/MS in measuring drug concentrations in serum or plasma, analysis of lacosamide (Vimpat™) is discussed in this chapter. Lacosamide is an example of the newer-generation AEDs. The drug is extracted by protein precipitation and dilution of the serum specimen. A small volume of the extracted specimen is injected into a reversed-phase chromatography column, and lacosamide is identified by positive electrospray ionization (ESI) mass spectrometry in the multiple reaction monitoring (MRM) mode, which provides selectivity for quantitative analysis. A deuterated internal standard is used to correct for any loss of analyte during the process of extraction and analysis. A seven-point calibration curve and two levels of quality controls are included in each batch.


Assuntos
Anticonvulsivantes/farmacocinética , Cromatografia Líquida , Monitoramento de Medicamentos , Lacosamida/farmacocinética , Espectrometria de Massas em Tandem , Interpretação Estatística de Dados , Monitoramento de Medicamentos/métodos , Monitoramento de Medicamentos/normas , Humanos
3.
Epilepsy Res ; 93(1): 11-6, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21145707

RESUMO

Rectal administration of diazepam (DZ) has been used effectively in patients with epilepsy who experience acute repetitive seizures, but rectal gel may be difficult to administer during a seizure and is subject to variable drug absorption. An intramuscular (IM) autoinjector DZ formulation may offer a practical alternative to rectal DZ. This single-center, open-label, 3-treatment, 3-period crossover study compared the pharmacokinetic and safety profiles of 10mg DZ administered rectally in 24 healthy, fasted and fed subjects versus IM autoinjector delivery in fasted subjects. Blood samples were collected at baseline and for up to 24h postdose and plasma DZ concentrations were determined by liquid chromatography and tandem mass spectrometry. There were no significant differences between plasma concentrations for rectal administration of DZ in fasted and fed subjects at any time point. Intramuscular DZ administration resulted in more rapid and less variable drug absorption than rectal delivery. At 30min postdose and at all subsequent evaluations, IM administration resulted in significantly higher areas under the curve versus rectal administration in fasted subjects (p<0.05). This significant difference was sustained throughout the remainder of the 24-h study period (p<0.05). All reported adverse events were considered mild, and none required treatment.


Assuntos
Administração Retal , Anticonvulsivantes/farmacocinética , Diazepam/farmacocinética , Sistemas de Liberação de Medicamentos/métodos , Injeções Intramusculares , Adolescente , Adulto , Análise de Variância , Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/sangue , Estudos Cross-Over , Diazepam/administração & dosagem , Diazepam/sangue , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Adulto Jovem
4.
J Chromatogr A ; 1083(1-2): 127-32, 2005 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-16078698

RESUMO

Aflatoxins produced by food-borne molds are known carcinogenic toxins. Aflatoxin B1 (AFB1) is reported as the most toxic of this class of mycotoxins. We have coupled immunoaffinity column extraction with LC/MS to produce a sensitive and selective approach for the study of AFB1. As AFB1 can be potentially found in tobacco it is of interest to establish whether AFB1 can be transferred from a cigarette fortified with AFB1, to the sidestream smoke. Previous studies have found that AFB1 does not transfer to the mainstream smoke. Since sidestream smoke may contain higher concentrations of some smoke components, a method was developed to analyze the sidestream smoke produced from machine-smoked cigarettes. Sidestream smoke condensates collected on Cambridge filter pads were extracted with isopropanol, then further purified using immunoaffinity extraction columns. The extracts were then analyzed by LC/MS and LC/MS/MS. An instrumental limit of detection (LOD) was established at 3.75 pg injected on column, with the limit of quantitation (LOQ) equal to 11.25 pg on column for both LC/MS and LC/MS/MS. The instrument was found to be linear from 11.25 pg to 150 pg (r > 0.995.) Precision ranged from 4.2% to 8.4% at the LOQ, while accuracy ranged from 0.53% to 1.33%. The immunoaffinity extraction method LOD was determined to be 100 pg fortified onto the Cambridge filter. The LOQ was 350 pg. The average recovery of the AFB1 from the Cambridge pad was 82.9% over the range of 100-1000 pg fortified onto the pad. AFB1 was not detected in unfortified cigarettes. A transfer experiment, fortifying cigarettes at 1 microg/cigarette determined that AFB1 was transferred only slightly from the burning cigarette to the sidestream smoke. The mean percent transfer was 0.087%.


Assuntos
Aflatoxina B1/análise , Nicotiana/química , Fumaça/análise , Cromatografia de Afinidade/métodos , Cromatografia Líquida , Imunoensaio/métodos , Espectrometria de Massas , Sensibilidade e Especificidade
5.
J Anal Toxicol ; 29(7): 704-10, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16419404

RESUMO

A method for the direct analysis of 10 opiate compounds in urine was developed using liquid chromatography-mass spectrometry-mass spectrometry (LC-MS-MS) with electrospray ionization interface (ESI). Opiates included were morphine-3-P-glucuronide, morphine-6--glucuronide, morphine, oxymorphone, hydromorphone, norcodeine, codeine, oxycodone, 6-monoacetylmorphine (6MAM), and hydrocodone. Urine samples were prepared by centrifugation to remove large particles and direct injection into the LC-MS-MS. Separation and detection of all compounds was accomplished within 6 min. Linearity was established for all opiates except 6MAM from 50 ng/mL to 10,000 ng/mL; 6MAM from 0.25 ng/mL to 50 ng/mL with all correlation coefficients (r) > 0.99. Interrun precision (%CV) ranged from 1.1% to 16.7%, and intrarun precision ranged from 1.3% to 16.3%. Accuracy (% bias) ranged from -7.3% to 13.6% and -8.5% to 11.8 for inter- and intrarun, respectively. Eighty-nine urine samples previously analyzed by gas chromatography-MS were re-analyzed by the LC-MS-MS method. The qualitative results found an 88% agreement for negative samples between the two methods and 94% for positive samples. The LC-MS-MS method identified 19 samples with additional opiates in the positive samples. Overall, the direct injection LC-MS-MS method performed well and permitted the rapid analysis of urine samples for several opiates simultaneously without extensive sample preparation.


Assuntos
Cromatografia Líquida de Alta Pressão , Entorpecentes/urina , Transtornos Relacionados ao Uso de Opioides/urina , Espectrometria de Massas por Ionização por Electrospray/métodos , Detecção do Abuso de Substâncias/métodos , Cromatografia Gasosa-Espectrometria de Massas , Glucuronídeos/urina , Humanos , Transtornos Relacionados ao Uso de Opioides/diagnóstico , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray/instrumentação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA