A rapid and fully-automated method for the quantitation of tricyclic antidepressants in serum using turbulent-flow liquid chromatography–tandem mass spectrometry

BackgroundWe describe a fully-automated turbulent-flow liquid chromatography–tandem mass spectrometry method for the detection of tricyclic antidepressant drugs (amitriptyline, desipramine, imipramine, and nortriptyline) in serum.MethodsHuman serum and an internal standard were injected directly onto a Cyclone-P online solid-phase extraction (SPE) column (0.5 × 50 mm). Following removal of serum proteins and other components the analytes were transferred to a Hypersil Gold C-18 (50 × 3 mm) analytical column. Elution occurred with a gradient of water and acetonitrile each with 0.1% formic acid. Analytes were ionized and detected over a 3.5 min analysis time by electrospray-ionization mass spectrometry with selected reaction monitoring (SRM). Matrix effects were well-characterized and carryover, precision, linearity, recovery and limits of detection and quantitation were evaluated.ResultsThe simple and complex precision CVs for all compounds were ≤ 16%. The limits of detection and quantitation for all drugs were ≤ 3 ng/ml and < 20 ng/ml, respectively. Recoveries were between 97 and 114%. Slopes for method comparison plots were all > 0.96. Proficiency testing materials had values within 2 SDI of peer group means for all drugs.ConclusionBased on validation data, this is a specific, sensitive fully-automated method for rapid quantitation of tricyclic antidepressants in serum.