Comparison of two extraction methods for determination of propranolol and furosemide in human plasma by mixed-mode chromatography

详细信息    查看全文

• 作者：Walshe ; Michaela ; Kelly ; Mary T. ; Smyth ; Malcolm R.
• 关键词：Mixed-mode chromatography ; Column switching ; Propranolol ; Furosemide ; Plasma
• 刊名：Journal of Pharmaceutical and Biomedical Analysis
• 出版年：1996
• 出版时间：February, 1996
• 年：1996
• 卷：14
• 期：4
• 页码：475-481
• 全文大小：405 K

文摘

An isocratic high performance liquid chromatographic method is described for the determination of the β-adrenergic blocking drug, propranolol, and the diuretic, furosemide, in human plasma. The two compounds and the internal standard were extracted from plasma using a two-step extraction technique. Propranolol and pindolol (internal standard) were first extracted from alkaline plasma into diethyl ether; this was followed by extraction of furosemide into acidified ether: hexane (65:35). The two extracts were then combined and evaporated under nitrogen, and the reconstituted residues were analysed on a C18/SCX reversed-phase/cation exchange column with a mobile phase of acetonitrile: 0.1 M sodium acetate pH 4 (33:67). The drugs and the internal standard were detected by UV absorption at 230 nm. The drugs were also extracted from plasma by a column-switching technique utilizing a ten-port valve. The drug compounds were retained on a C18 pre-column. A comparison of RSD for within-batch (intra-assay) and between-batch (inter-assay) runs for both methods was carried out, the liquid/liquid extraction method giving better recovery values. The calibration graphs were linear from 25-300 ng ml⁻¹ for furosemide and 50-400 ng ml⁻¹ for propranolol. Recovery values were > 90.0 % by liquid/liquid extraction and > 76.0 % by column switching.