Determination of diltiazem in human whole blood and plasma by high-performance liquid chromatography using a polymeric reversed-phase column and utilizing a salting-out extraction procedure.
A rapid, simple and sensitive reversed-phase high-performance liquid chromatography method for the separation and measurement of the concentration of diltiazem in human whole blood and plasma has been developed. The method involves a simple one-step solvent extraction of the drug from biological samples followed by salting-out the organic solvent using ammonium sulfate. A 15 cm x 4.1 mm, PRP-1, pH-stable (pH 1-13) polymeric reversed-phase column was used with an isocratic elution of acetonitrile-0.01 M tetrabutylammonium hydroxide (60:40, v/v). Diltiazem was monitored at 254 nm and 0.50-0.005 a.u.f.s. The completion time for assay was less than 15 min, and the limit of detection was 10 ng/ml at a signal-to-noise ratio of 3 for a 50-microliters injection volume. Using this method, the pharmacokinetic parameters (elimination rate constant, elimination half-life and area under the curve) were calculated from a whole blood concentration versus time profile of diltiazem.
Department of Metabolism and Environmental Fate Chemistry, Hazleton Laboratories America, Inc., Madison, WI 53704.
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D002851:Chromatography, High Pressure Liquid; D004110:Diltiazem / Q000097:blood*; D006801:Humans; D013056:Spectrophotometry, Ultraviolet
D004110:Diltiazem