title: LC-MS method for the estimation of delta8-THC and 11-nor-delta8-THC-9-COOH in plasma.
abstract: The aim of the present study was to develop a simple and sensitive LC-MS method for the estimation of delta8-tetrahydrocannabinol (delta8-THC) and its metabolite, 11-nor-delta8-tetrahydrocannabinol-9-carboxylic acid (11-nor-delta8-THC-9-COOH), in guinea pig plasma after topical drug application. The plasma samples were analyzed by LC-MS using negative-mode electrospray ionization detection and a simple liquid-liquid extraction technique. The mean recoveries for delta8-THC and its metabolite, 11-nor-delta8-THC-9-COOH, were 96.6 and 88.2%, respectively. The lower limits of quantification (LLOQ) for delta8-THC and 11-nor-delta8-THC-9-COOH were 3.97 and 7.26 nM, respectively. The topical treatment steady-state plasma concentrations of delta8-THC and 11-nor-delta8-THC-9-COOH were 8.24-27.63 and 19.66-23.17 nM, respectively, with a lag period of 0.3-2.2 h. This assay method is selective, sensitive, and reproducible for the determination of delta8-THC and 11-nor-delta8-THC-9-COOH at low concentrations in small volumes of plasma.
authors.affiliation: Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 725 Rose Street, Lexington, KY 40536-0082, USA.
authors.forename: Satyanarayana
authors.initials: S
authors.lastname: Valiveti
authors.forename: Dana C
authors.initials: DC
authors.lastname: Hammell
authors.forename: D Caroline
authors.initials: DC
authors.lastname: Earles
authors.forename: Audra L
authors.initials: AL
authors.lastname: Stinchcomb
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D013759:Dronabinol / Q000031:analogs & derivatives* / Q000097:blood* / Q000493:pharmacokinetics; D006168:Guinea Pigs; D013058:Mass Spectrometry / Q000379:methods*; D012015:Reference Standards; D012680:Sensitivity and Specificity
chemical_list: C009411:delta(6)-tetrahydrocannabinol-7-oic acid; D013759:Dronabinol