title: A rapid and reliable method for the quantitation of tricyclic antidepressants in serum using HPLC-MS/MS.
abstract: OBJECTIVE
  Here we describe a liquid chromatography-tandem mass spectrometry method for the detection of tricyclic antidepressant drugs (amitriptyline, desipramine, imipramine, and nortriptyline) in serum.
  
  
  METHODS
  Following a protein precipitation from serum and dilution of supernatant with water, these analytes and their internal standards (deuterated versions of each drug) were injected, separated, and eluted from a Hypersil Gold C-18 (50x2.1 mm) analytical column with a gradient of water and acetonitrile each with 0.1% formic acid. Analytes were then ionized and detected over a 3.5 minute analysis time by electrospray ionization mass spectrometry with multiple reaction monitoring. Matrix effects were characterized using three methods: post-column infusion, pre- and post-extraction addition of analyte to matrix, and comparison of neet to serum preparations.
  
  
  RESULTS
  The inter-day and intra-day coefficients of variation for all compounds were < or =12%. The limit of detection for all drugs was <15 ng/mL and the limit quantitation for all drugs was <22 ng/mL. Recoveries were between 97 and 131% for all drugs. Patient method comparison and proficiency samples were run with acceptable results.
  
  
  CONCLUSIONS
  We have developed a specific and sensitive method for rapid quantitation of tricyclic antidepressants in serum, suitable for use in the clinical laboratory.
authors.affiliation: The Johns Hopkins University Department of Pathology, Baltimore, Maryland, USA.
authors.forename: Autumn R
authors.initials: AR
authors.lastname: Breaud
authors.forename: Robert
authors.initials: R
authors.lastname: Harlan
authors.forename: Marta
authors.initials: M
authors.lastname: Kozak
authors.forename: William
authors.initials: W
authors.lastname: Clarke
mesh_terms: D000929:Antidepressive Agents, Tricyclic / Q000097:blood*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006801:Humans; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D053719:Tandem Mass Spectrometry / Q000379:methods*; D013997:Time Factors
chemical_list: D000929:Antidepressive Agents, Tricyclic