title: A sensitive and rapid method for quantification of lacosamide and desmethyl lacosamide by LC-MS/MS.
abstract: BACKGROUND
  Monitoring lacosamide (LCM) helps optimize therapeutic dosing in some clinical settings. We developed a novel LC-MS/MS method for measuring serum LCM and O-desmethyl lacosamide (ODL).
  
  
  CONCLUSIONS
  The sample preparation was protein precipitation with methanol. The total CV was less than 4.7%. Calibration range was 0.95-30.29 µg/ml and 0.95-30.41 µg/ml while the expanded linear range was 0.41-47.49 µg/ml and 0.34-48.17 µg/ml for LCM and ODL, respectively with analytical accuracy of 87.2-106.0%. 45 random serum samples collected from 23 individuals on either 200 mg/day or 400 mg/day of LCM therapy showed concentrations of 2.2-19.8 µg/ml for LCM and up to 2.5 µg/ml for ODL.
  
  
  CONCLUSIONS
  A simple and sensitive LC-MS/MS assay was validated for quantification of LCM and ODL in human serum.
authors.affiliation: Department of Clinical Pathology, Cleveland Clinic, Cleveland, OH 44195, USA.
authors.forename: Drew
authors.initials: D
authors.lastname: Payto
authors.forename: Nancy
authors.initials: N
authors.lastname: Foldvary-Schaefer
authors.forename: Norman
authors.initials: N
authors.lastname: So
authors.forename: Monica
authors.initials: M
authors.lastname: Bruton
authors.forename: Sihe
authors.initials: S
authors.lastname: Wang
mesh_terms: D000081:Acetamides / Q000097:blood* / Q000737:chemistry*; D001774:Blood Chemical Analysis / Q000379:methods*; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D000078334:Lacosamide; D053719:Tandem Mass Spectrometry; D013997:Time Factors
chemical_list: D000081:Acetamides; D000078334:Lacosamide
keywords: O-desmethyl lacosamide; lacosamide; liquid chromatography; mass spectrometry