Solid-phase extraction with HPLC-DAD selective detection of amitriptyline and nortriptyline in human breast milk

A simple, rapid, highly selective and sensitive method was developed to det ermine concentrations of amitriptyline and nortriptyline in human breast mi lk, using high performance liquid chromatography (HPLC) with a diode-array detector (DAD). Drugs were effectively extracted from 250 muL of milk by a solid phase extraction procedure on a polymeric sorbent-C18-based cartridge . The separation was carried out on a Eclipse XDB-C18 reversed phase column (30 mm x 4.6 mm, 3.5 mum particle size) using the mobile phase composed of acetonitrile and ammonium acetate 0.1M (33/67, v/v). Imipramine was used a s internal standard. Calibration functions were linear in the calibration r ange of 60-300 ng.mL(-1). The lower limit of detection was 1.9 ng.mL(-1) fo r both compounds. The recoveries were 92% for amitriptyline and 89% for nor triptyline. Since no method have been reported in the literature for the do sage of these two drugs in breast milk, this method could be useful, partic ularly, when evaluating the potential risk for the neonate during the lacta tion period.