Urinary excretion profiles of the orexin receptor antagonist suvorexant and its metabolites.

Purpose: Suvorexant is an orexin receptor antagonist used in the treatment of insomnia. In this study, we investigated the urinary excretion profiles of suvorexant and its major metabolites, including conjugates, to obtain fundamental information for proving exposure to suvorexant in criminal cases.

Methods: Urine specimens were collected from three subjects for maximum 168 h after a single oral ingestion of suvorexant (10 mg), and suvorexant and its metabolites in urine were determined using liquid chromatography-tandem mass spectrometry with a C18 semi-micro column.

Incorporation of suvorexant and lemborexant into hair and their distributions after a single intake.

Purpose: This study examined the applicability of hair analysis as an approach to identify suvorexant (SUV) and lemborexant (LEM) intake by analyzing black hair specimens collected from study participants after a single oral administration.

Methods: Hair specimens were collected form participants who took a single dose of 10 mg SUV or 5 mg LEM. Identification of the dual orexin receptor antagonists (DORAs) and their metabolites was performed by liquid chromatography-tandem mass spectrometry.

Human and rat microsomal metabolites of N-tert-butoxycarbonylmethamphetamine and its urinary metabolites in rat.

Purpose: N-tert-Butoxycarbonylmethamphetamine (BocMA), a masked derivative of methamphetamine (MA), converts into MA under acidic condition and potentially acts as a precursor to MA following ingestion. To investigate the metabolism and excretion of BocMA, metabolism tests were conducted using human liver microsomes (HLM), rat liver microsomes (RLM) and rat.

Methods: BocMA metabolites were analyzed after 1000-ng/mL BocMA incubation with microsomes for 3, 8, 13, 20, 30, and 60 min.

Incorporation of five common hypnotics into hair after a single dose and application to a forensic case of drug facilitated crimes.

In order to obtain fundamental information on the disposition of hypnotics into hair after a single oral dose the quantitative hair analysis of triazolam (TZ), etizolam (EZ), flunitrazepam (FNZ), nitrazepam (NZ) and zolpidem (ZP) have been performed using a validated LC-MS/MS procedure. Hair specimens (straight, black) were collected from three subjects about one month and three months after a single 0.25 mg dose of TZ, 1 mg of EZ, 2 mg of FNZ, 5 mg of NZ and 10 mg of ZP tartrate.

Incorporation of Methoxyphenamine into Hair in Early Stage after Intake.

In order to investigate the incorporation behavior of drugs into hair in early stage (within 24 h) after intake, time-course changes in drug distribution in black hair were carefully analyzed after a single oral administration of methoxyphenamine (MOP), a non-regulated analog of methamphetamine. Single-hair specimens collected by plucking with the roots intact at appropriate intervals post-intake were each divided into 1-mm segments from the proximal end, and MOP in each segment was determined by a validated liquid chromatography-tandem mass spectrometry procedure. At 10 min after intake, MOP was not detected in any of the segments.

Dehydration-fragmentation mechanism of cathinones and their metabolites in ESI-CID.

Various cathinone-derived designer drugs (CATs) have recently appeared on the drug market. This study examined the mechanism for the generation of dehydrated ions for CATs during electrospray ionization collision-induced dissociation (ESI-CID). The generation mechanism of dehydrated ions is dependent on the amine classification in the cathinone skeleton, which is used in the identification of CATs.

Effects of lipophilicity and functional groups of synthetic cannabinoids on their blood concentrations and urinary excretion.

The influence of lipophilicity and functional groups of synthetic cannabinoids (SCs) on their blood concentrations and urinary excretion has been studied by analyzing blood and urine specimens sampled from drivers who were involved in a car crashes under the influence of SCs. A total of 58 specimens (26 urine and 31 blood specimens), sampled within 13h of the occurrence, were analyzed by liquid chromatography-tandem mass spectrometry. Fifteen SCs were detected in those specimens; the SCs detected were categorized as follows: Class 1, Naphthoyl/Benzoyl indole (EAM2201 and three other analogs); Class 2, Indole-3-carboxylate/carboxamide containing naphthol/quinol (5F-PB-22 and four other analogs); and Class 3, Indazole-3-carboxamide containing valine/tert-leucine derivative (5F-AMB and five other analogs).

Incorporation of zolpidem and methoxyphenamine into white hair strands after single administrations: Influence of hair pigmentation on drug incorporation.

In order to investigate the influence of pigmentation on the incorporation of drugs into hair, time-course changes in drug distribution along non-pigmented (white) hairs as well as pigmented (black) hairs plucked from the same subject was observed following single administrations of two basic drugs with different properties, zolpidem and methoxyphenamine. These drugs in 1-mm sections of single hair specimens were each determined by a liquid chromatography-tandem mass spectrometric procedure. During the early stage (12-36 h) after intake, for black hairs, both drugs were detected over the entire area of hair root (4-5 mm in length), in which notable concentration of these drugs in the hair bulb (0-1-mm segment from the bottom of hair root, Region 1) and lower concentrations in the upper dermis zone (1-2-mm to 3-4-mm or to 4-5-mm segments, Region 2) were commonly observed.

Incorporation of Zolpidem into Hair and Its Distribution after a Single Administration.

To obtain fundamental information on the drug incorporation into hair, time-course changes in drug distribution along single-strand hair were observed after a single oral administration of zolpidem (ZP), one of the most frequently used hypnotic agents. Quantitative sectional hair analyses of 1-mm segments were performed for each single-strand hair using a validated LC-MS/MS procedure. ZP was detected in all specimens plucked at 10 and 24 hours after a single dose, and the distribution ranged over the whole hair root (4-5 mm in length).

Quantitative and antioxidative behavior of Trolox in rats' blood and brain by HPLC-UV and SMFIA-CL methods.

Trolox, a water-soluble vitamin E analogue has been used as a positive control in Trolox equivalent antioxidant capacity and oxygen radical antioxidant capacity assays due to its high antioxidative effect. In this study, the ex vivo antioxidative effects of Trolox and its concentration in blood and brain microdialysates from rat after administration were evaluated by newly established semi-microflow injection analysis, chemiluminescence detection and HPLC-UV. In the administration test, the antioxidative effect of Trolox in blood and brain microdialysates after a single administration of 200 mg/kg of Trolox to rats could be monitored.