Determination of phenobarbital in human plasma by a specific liquid chromatography method: application to a bioequivalence study

• Published in: Química nova Vol. 33; no. 1; pp. 124 - 129
• Main Authors: Dalmora, Sérgio Luiz, Sangoi, Maximiliano da Silva, Nogueira, Daniele Rubert, D'Avila, Felipe Bianchini, Moreno, Ronílson Agnaldo, Sverdloff, Carlos Eduardo, Oliveira, Rogério Antonio de, Borges, Ney Carter
• Format: Journal Article
• Language: English
• Published: Sociedade Brasileira de Química 2010
• Subjects: human plasma; liquid chromatography; phenobarbital
• ISSN: 0100-4042; 1678-7064
• DOI: 10.1590/S0100-40422010000100023

A liquid chromatography method was developed and validated for the determination of phenobarbital in human plasma using phenytoin as internal standard. The drugs were extracted from plasma by liquid-liquid extraction and separated isocratically on a C12 analytical column, maintained at 35 ºC, with water:acetonitrile:methanol (58.8:15.2:26, v/v/v) as mobile phase, run at a flow rate of 1.2 mL/min with detection at 205 nm. The method was linear in the range of 0.1-4 μg/mL (r²=0.9999) and demonstrated acceptable results for the precision, accuracy and stability studies. The method was successfully applied for the bioequivalence study of two tablet formulations (test and reference) of phenobarbital 100 mg after single oral dose administration to healthy human volunteers.