Determination of olanzapine in plasma by high-performance liquid chromatography using ultraviolet absorbance detection.
A rapid method for the determination of olanzapine in plasma using high-performance liquid chromatography with ultra violet detection is described. Olanzapine was extracted from plasma with a mixture of hexane/dichloromethane (85:15), and then back extracted into phosphate buffer pH 2.8. Separation was achieved on a RP Select B C(18) column and commonly administered drugs did not interfere with the assay. The limit of quantitation was 1.5 microg/l and the inter-day and intra-day relative standard deviations were less than 10%. Olanzapine was shown to be stable in plasma for up to 7 days when stored at 4 degrees C. Moreover, the addition of ascorbic acid was not necessary for the achievement of chemical stability during storage, or during the assay procedure. The method has been used to measure olanzapine concentrations in patients treated with various doses of the drug varying from 5 to 40 mg/day.
Dusci
Leon J
LJ
Clinical Pharmacology and Toxicology Laboratory, The Western Australian Centre for Pathology and Medical Research, Locked Bag 2009, Nedlands 6009, Australia. leon.dusci@health.wa.gov.au
Peter Hackett
L
L
Fellows
Linda M
LM
Ilett
Kenneth F
KF
D014150:Antipsychotic Agents / Q000097:blood*; D001569:Benzodiazepines; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006801:Humans; D000077152:Olanzapine; D010890:Pirenzepine / Q000031:analogs & derivatives / Q000097:blood*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013056:Spectrophotometry, Ultraviolet / Q000379:methods*
D014150:Antipsychotic Agents; D001569:Benzodiazepines; D010890:Pirenzepine; D000077152:Olanzapine