RESUMO
Regadenoson, the first selective adenosine A2A receptor agonist, is used to perform exercise stress test during radionuclide myocardial perfusion imaging. To detect the concentration of regadenoson in human plasma, a simple, fast, and sensitive tandem mass spectrometry method was established herein. Acetonitrile was used as a protein precipitation agent. Chromatographic separation was completed in 6.5 min using a BEH HILIC column (50 × 2.1 mm, 1.7 µm). The mobile phase consisted of 10 mmol/L ammonium acetate/acetonitrile (gradient elution). To quantify regadenoson and regadenoson-d3, an API 4000 mass spectrometry in multiple reaction monitoring mode with transitions of 391.3â259.2 and 394.3â262.2, respectively, was utilized. The calibration curve was linear in the range of 0.100-50.0 µg/L, and the intrabatch and interbatch precisions were <9.7% and <13.0%, respectively, and the accuracy was 2.0-6.9%. There was no apparent matrix effect for regadenoson or regadenoson-d3. The developed method was used to study the pharmacokinetic characteristics of regadenoson in healthy Chinese subjects.
Assuntos
Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida/métodos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Purinas , Pirazóis , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodosRESUMO
A convenient and sensitive liquid chromatography-tandem mass spectrometry method was established to simultaneously quantify voriconazole (VRZ) and its metabolite, voriconazole N-oxide (VNO), in human urine. Voriconazole-d3 and voriconazole-d3 N-oxide were used as isotopic internal standards. Samples were processed by protein precipitation and separated using a ZORBAX SB-Aq column (1.8 µm, 2.1 × 50 mm). Mass spectrometry was performed using an API 4000 mass spectrometry by positive electrospray ionization. The flow rate was 0.6 mL/min. Gradient elution was performed with methanol and 0.1% formic acid as the organic and water phase, respectively. The VRZ and VNO calibration curves ranged from 20.0 to 7200 ng/mL in human urine. The specificity, matrix effect, extraction recovery, intra/inter-run precision, accuracy and stability were validated for both VRZ and VNO in human urine. The developed method was used to study urinary excretion after intravenous injection of 4 mg/kg VRZ in healthy Chinese subjects.