RESUMO
A moderately high resolution nanoelectrospray ionization gas-phase electrophoresis instrument was constructed and evaluated for simple high-speed separations of several groups of compounds. The insertion of a plate containing a 1.6 cm diameter exit orifice, 2.5 cm from the location of electrospray, allowed ions to be created and desolvated under ambient conditions with minimal solvent contamination to the drift tube. Ion separation selectivity is discussed and shown to be slightly altered by changing the drift gas flow rate. Issues of using gas-phase electrophoresis as a high-speed separation technique are discussed. Gas-phase electrophoresis-spectra of selected benzodiazepines, triazine herbicides, and simple combinatorial chemistry libraries are demonstrated.
Assuntos
Ansiolíticos/análise , Eletroforese/métodos , Herbicidas/análise , Alprazolam/análise , Técnicas de Química Combinatória , Diazepam/análise , Eletroforese/instrumentação , Desenho de Equipamento , Nitrazepam/análise , Oxazepam/análise , Prazepam/análise , Fatores de Tempo , Triazinas/análiseRESUMO
A supercritical fluid extraction (SFE) procedure for the analysis of temazepam from whole blood was developed. Quantitative recoveries were obtained by high-performance liquid chromatography using prazepam as an internal standard and carefully monitoring the extraction temperature and pressure. The results were found to compare well with those obtained by solid-phase extraction techniques, but they also had the advantages of reduced solvent consumption and minimal sample handling. The application of this method to authentic forensic blood specimens showed the SFE method to be useful as an alternative procedure for the extraction of temazepam in the toxicology laboratory.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicina Legal , Prazepam/análise , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Temazepam/sangue , Humanos , Padrões de Referência , Reprodutibilidade dos TestesRESUMO
The development of a radioimmunoassay for the analysis of prazepam and its metabolites is described. It includes the preparation of the immunogen, immunization and measurement of specificity and sensitivity.
Assuntos
Prazepam/análise , Animais , Nordazepam/análise , Oxazepam/análise , Prazepam/metabolismo , Coelhos , RadioimunoensaioRESUMO
Methods have been developed for the determination of the benzodiazepine tranquilizer prazepam and its metabolites desmethyl diazepam, 3-hydroxy-prazepam and oxazepam by electron capture gas chromatography and selected ion monitoring with diazepam as the internal standard. The benzodiazepines were isolated from blood serum or homogenized tissue samples, either by extraction with ethyl acetate or on small Extrelut columns packed with porous silica. The concentrated extracts were directly injected into the gas chromatograph equipped with an electron capture detector. Following trimethylsilylation, analysis on a gas chromatography--mass spectrometry--computer system operated in the selected ion-monitoring mode was performed. Using 50--200 mg (microliter) biological material, concentrations of prazepam and metabolites of 5 ng/g(ml) could be determined with signal-to-noise ratios of greater than 10. Using 1 g(ml) samples, the same signal-to-noise ratios were obtained with 1 ng/g(ml) concentrations. The methods developed were applied to the analysis of the diaplacental transfer of prazepam and desmethyl diazepam in early human pregnancy. Furthermore, prazepam metabolism in human fetal liver and cell cultures was studied.
