title: Reversed-phase liquid-chromatographic simultaneous analysis for thiopental and pentobarbital in serum.
abstract: We describe a reversed-phase liquid-chromatographic assay suitable for therapeutic monitoring of thiopental and pentobarbital simultaneously in human serum. The drugs are extracted from serum at pH 6.6 into n-butyl chloride containing thiamylal and barbital as the respective internal standards. The compounds are back-extracted into dilute sodium hydroxide, an aliquot of which is submitted to chromatography. The lowest measurable concentrations are 1.0 mg/L for thiopental and 2.0 mg/L for pentobarbital. The standard curve is linear from 0 to 100 mg/L for both. Between-run CVs are: at 25 mg/L, 4.1% (thiopental) and 3.2% (pentobarbital); at 50 mg/L, 2.8% (thiopental) and 3.4% (pentobarbital). Data on patients receiving thiopental and pentobarbital illustrate use of the method.
mesh_terms: D002851:Chromatography, High Pressure Liquid; D005189:False Positive Reactions; D006801:Humans; D006863:Hydrogen-Ion Concentration; D010634:Phenobarbital / Q000097:blood* / Q000302:isolation & purification / Q000627:therapeutic use; D013874:Thiopental / Q000097:blood* / Q000302:isolation & purification / Q000627:therapeutic use
chemical_list: D013874:Thiopental; D010634:Phenobarbital