title: Determination of tapentadol (Nucynta®) and N-desmethyltapentadol in authentic urine specimens by ultra-performance liquid chromatography-tandem mass spectrometry.
abstract: Urine specimens from pain management patients dosed with Nucynta (Tapentadol) were confirmed for the presence of tapentadol and N-desmethyltapentadol using ultra-performance liquid chromatography-tandem mass spectrometry to minimize sample preparation and urine volume requirements. The linearity of the method for both tapentadol and N-desmethyltapentadol demonstrated correlation coefficients (R²) above 0.99 and linear ranges from 50 to 500,000 ng/mL for tapentadol and 100 to 500,000 ng/mL for N-desmethyltapentadol. The intraday precision of the assay for both analytes ranged from 2.2 to 6.9% over three concentrations; the interday precision for both analytes ranged from 1.2 to 8.4%. The limits of quantitation were 50 and 100 ng/mL for tapentadol and N-desmethyltapentadol, respectively, and the upper limit of linearity for both analytes was determined to be 500,000 ng/mL. Urine samples were collected within 24 h of dosing with tapentadol and shipped overnight to the laboratory. Samples were hydrolyzed with acid prior to analysis to measure total (unconjugated and conjugated) tapentadol and N-desmethyltapentadol. Further investigation into characterization of metabolites was performed by using a hybrid quadrupole-time-of-flight mass spectrometer in lieu of suitable analytical reference standards. The presence of significant N-desmethyltapentadol glucuronide was demonstrated for the first time.
authors.affiliation: Ameritox, 9930 West Highway 80, Midland, Texas 79706, USA.
authors.forename: James A
authors.initials: JA
authors.lastname: Bourland
authors.forename: Ayodele A
authors.initials: AA
authors.lastname: Collins
authors.forename: Scot A
authors.initials: SA
authors.lastname: Chester
authors.forename: Sumankalai
authors.initials: S
authors.lastname: Ramachandran
authors.forename: Ronald C
authors.initials: RC
authors.lastname: Backer
mesh_terms: D000700:Analgesics / Q000652:urine*; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D059408:Pain Management / Q000379:methods; D010636:Phenols / Q000652:urine*; D017450:Receptors, Opioid, mu / Q000037:antagonists & inhibitors*; D015203:Reproducibility of Results; D053719:Tandem Mass Spectrometry / Q000379:methods*; D000077432:Tapentadol
chemical_list: D000700:Analgesics; C568350:N-desmethyltapentadol; D010636:Phenols; D017450:Receptors, Opioid, mu; D000077432:Tapentadol