Quantification of olanzapine and its three metabolites by liquid chromatography-tandem mass spectrometry in human body fluids obtained from four deceased, and confirmation of the reduction from olanzapine N-oxide to olanzapine in whole blood in vitro.

PURPOSE: Quantification of olanzapine (OLZ) and its metabolites such as N-desmethylolanzapine (DM-O), 2-hydroxymethylolanzapine (2H-O) and olanzapine N-oxide (NO-O) in five kinds of human body fluids including whole blood by liquid chromatography (LC)-tandem mass spectrometry (MS/MS) has been presented; the quantification methods were carefully devised and validated using the matrix-matched calibration and standard addition methods. METHODS: OLZ and its three metabolites were extracted from 40 µL each of body fluids by two-step liquid-liquid separations. The samples and reagents were pre-cooled in a container filled with ice for the extraction because of the thermal instability of OLZ and its three metabolites especially in whole blood. RESULTS: The limits of quantification (LOQs) of OLZ and 2H-O were 0.05 ng/mL and those of DM-O and NO-O were 0.15 ng/mL in whole blood and urine, respectively. The concentrations of OLZ and its metabolites in heart whole blood, pericardial fluid, stomach contents, bile and urine were determined for two cadavers and those in whole blood and urine for the other two cadavers. The reduction from NO-O to OLZ was observed at 25 â„ƒ in whole blood in vitro. CONCLUSIONS: To our knowledge, this is the first report on the quantification of metabolites of olanzapine in the authentic human body fluids by LC-MS/MS as well as on the confirmation of in vitro reduction from NO-O to OLZ in whole blood that seems to have induced the quick decrease of NO-O.

Quantification of risperidone and paliperidone by liquid chromatography-tandem mass spectrometry in biological fluids and solid tissues obtained from two deceased using the standard addition method.

Risperidone (RIS) is an atypical antipsychotic agent and its 9-hydroxylated metabolite named paliperidone (PAL) also has pharmacological properties similar to that of RIS. Quantifications of RIS and PAL in authentic human biological fluids and solid tissues by liquid chromatography (LC)-tandem mass spectrometry (MS/MS) have not been reported yet although those in plasma (and blood) were reported abundantly. In the present work, a quantification method for RIS and PAL based on the standard addition method was devised and validated for the human fluid and solid tissue specimens. RIS and PAL in biological fluids were quantified only after their dilution and deproteinization. The concentrations of RIS and PAL in the heart whole blood, pericardial fluid, stomach contents, bile, urine, liver, kidney and cerebrum were determined for a deceased who had been treated with RIS therapeutically, and also a deceased who had ingested RIS with other drugs intentionally. To our knowledge, this is the first report on the quantification of RIS and PAL by LC-MS/MS in the authentic human tissues and biological fluids.

Long-term stability of 24 synthetic cannabinoid metabolites spiked into whole blood and urine for up to 168 days, and the comparable study for the 6 metabolites in non-spiked real case specimens stored for 1-5 years.

PURPOSE: The aim of this study is to investigate the stabilities of the 24 synthetic cannabinoid metabolites (SCMs) in blood and urine at various temperatures from - 30 to 37 ℃ stored for 1-168 days. In addition, experiments of stabilities at lower temperatures and for much longer duration have been performed as described below. METHODS: The quantification was performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The blank blood and urine spiked with SCMs and non-spiked real case (authentic) specimens were incubated at 37 ℃ up to 56 days and at 22, 4 or - 30 ℃ up to 168 days. The non-spiked authentic blood and urine specimens were also stored at - 30 or - 80 ℃ for 1, 3 or 5 years to investigate stabilities during very long time frames. RESULTS: All the 24 SCMs were much more stable in urine than in blood at 37, 22 or 4 ℃. All 24 SCMs spiked into blood or urine were stable at - 30 ℃ for up to 168 days. The 6 SCMs in the authentic specimens exhibited long stabilities at - 30 or - 80 ℃ for 3-5 years. Some tendencies were observed according to the relation between the structures of SCMs and their stabilities. CONCLUSIONS: The long-term stabilities of 24 SCMs in spiked samples and those of 6 SCMs in the authentic specimens were examined using LC-MS/MS. SCMs were largely very stable and usable several years after storage at - 30 or - 80 ℃.