Amitriptyline and nortriptyline serum determination by micellar liquid chromatography

Abstract

Introduction Amitriptyline and nortriptyline are tricyclic antidepressants which act by enhancing the actions of norepinephrine and serotonin caused by blocking the re-uptake of various neurotransmitters at the neuronal membrane. A micellar liquid chromatographic procedure was developed to determine these drugs in serum samples for use in clinical monitoring. Methods The chromatographic determination of these highly hydrophobic substances was carried out using a 0.15 M SDS-6% ( v/ v) pentanol buffered at pH 7, in a C18 column, and electrochemical detection at 650 mV. The flow-rate was 1.5 mL/min. The analysis time was 14 min. Results The limits of detection (ng/mL) in serum were 0.25 and 0.31 for amitriptyline and nortriptyline, respectively. Repeatability and intermediate precision were evaluated at three different concentrations in serum samples. Discussion Untreated serum samples were injected directly into the HPLC system after filtration, leading to be a simple procedure that can be applied in routine analyses for Therapeutic Drug Monitoring.