title: HPLC method for determination of verapamil in human plasma after solid-phase extraction.
abstract: A simple, rapid and precise HPLC method has been developed for the assay of verapamil in human plasma. The clean up of the plasma samples was tested using several adsorbents for solid-phase extraction and best recovery was obtained using mixed-mode cartridges (HLB - hydrophilic-lipophilic balance) ranging between 94.70 and 103.71%. HPLC separation was performed with isocratic elution on Lichrospher 60 RP-select B column (250 mm x 4 mm I.D., 5 microm particle size). The mobile phase was 40% acetonitrile and 0.025 mol/L KH2PO4 with pH 2.5 at flow rate of 1 mL/min. Diltiazem was used as internal standard and the detection wavelength was 200 nm. The calibration curves were linear in the range of 10-500 ng/mL. The developed method is convenient for routine analysis of verapamil in human plasma.
authors.affiliation: Institute of Chemistry, Faculty of Science, Sts. Cyril and Methodius University, POB 162, 1000 Skopje, Republic of Macedonia.
authors.forename: Violeta
authors.initials: V
authors.lastname: Ivanova
authors.forename: Dragica
authors.initials: D
authors.lastname: Zendelovska
authors.forename: Marina
authors.initials: M
authors.lastname: Stefova
authors.forename: Trajce
authors.initials: T
authors.lastname: Stafilov
mesh_terms: D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation* / Q000379:methods*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D015394:Molecular Structure; D052616:Solid Phase Extraction / Q000295:instrumentation* / Q000379:methods*; D014700:Verapamil / Q000097:blood* / Q000737:chemistry
chemical_list: D014700:Verapamil