Mirtazapine (MTZ) is an antidepressant drug, which belongs to the chemical class of piperazinoazepines. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the quantifica- tion of MTZ ...Mirtazapine (MTZ) is an antidepressant drug, which belongs to the chemical class of piperazinoazepines. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the quantifica- tion of MTZ in plasma at the concentrations associated with therapy. Diazepam (DZP) was used as internal standard, added to 200 μL of plasma sample prior to a liquid-liquid extraction using hexane. Chroma- tographic separation was achieved on an Agilent? Eclipse XDB C-18 column (100 × 2.1 mm, 3.5 μm) in iso- cratic mode at 40?C. Mobile phase was 10 mM ammonium acetate/acetonitrile/formic acid (60/40/0.1, v/v/v) at a constant flow rate of 0.5 mL?min–1. The injection volume was 10 ?L and the total run time was 3.2 min. The method shows selectivity and linearity. The detection and quantitation limits were established at 0.17 and 0.50 ng?mL–1, respectively. The extraction recoveries for MTZ and DZP were found to be between 84.9 and 93.9%. The intra-day and inter-day precision and accuracy fulfill at the international acceptance criteria. The method shows to be stable for the studied parameters. Therefore, a rapid, specific, and sensitive LC-MS/MS method for quantification of MTZ in human plasma was developed and can be used in therapeu- tic drug monitoring of this drug.展开更多
An ion-exchange chromatography (IEC) followed by post-column derivatization method was validated for the determination of glutamine in food additive products. The chromatographic method was carried out on a sodium cat...An ion-exchange chromatography (IEC) followed by post-column derivatization method was validated for the determination of glutamine in food additive products. The chromatographic method was carried out on a sodium cation-exchange column and using detection at 570 nm. The mobile phase consisted of sodium eluant, pH 3.15, with 5% sulfolane, sodium eluant, pH 7.40 and sodium column regenerant. The method was linear in the range of 4 - 50 μg/mL (r2 = 0.9999). The accuracy was 99.78%. Moreover, method validation demonstrated acceptable results for precision and robustness. The method was found to be able to use for routine analysis of the glutamine.展开更多
文摘Mirtazapine (MTZ) is an antidepressant drug, which belongs to the chemical class of piperazinoazepines. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the quantifica- tion of MTZ in plasma at the concentrations associated with therapy. Diazepam (DZP) was used as internal standard, added to 200 μL of plasma sample prior to a liquid-liquid extraction using hexane. Chroma- tographic separation was achieved on an Agilent? Eclipse XDB C-18 column (100 × 2.1 mm, 3.5 μm) in iso- cratic mode at 40?C. Mobile phase was 10 mM ammonium acetate/acetonitrile/formic acid (60/40/0.1, v/v/v) at a constant flow rate of 0.5 mL?min–1. The injection volume was 10 ?L and the total run time was 3.2 min. The method shows selectivity and linearity. The detection and quantitation limits were established at 0.17 and 0.50 ng?mL–1, respectively. The extraction recoveries for MTZ and DZP were found to be between 84.9 and 93.9%. The intra-day and inter-day precision and accuracy fulfill at the international acceptance criteria. The method shows to be stable for the studied parameters. Therefore, a rapid, specific, and sensitive LC-MS/MS method for quantification of MTZ in human plasma was developed and can be used in therapeu- tic drug monitoring of this drug.
基金supported by CNPq-Brazil program and PACD-FCF-UNESP.
文摘An ion-exchange chromatography (IEC) followed by post-column derivatization method was validated for the determination of glutamine in food additive products. The chromatographic method was carried out on a sodium cation-exchange column and using detection at 570 nm. The mobile phase consisted of sodium eluant, pH 3.15, with 5% sulfolane, sodium eluant, pH 7.40 and sodium column regenerant. The method was linear in the range of 4 - 50 μg/mL (r2 = 0.9999). The accuracy was 99.78%. Moreover, method validation demonstrated acceptable results for precision and robustness. The method was found to be able to use for routine analysis of the glutamine.