Analysis of benzene ethylamine derivatives in urine using the programmable dynamic liquid-phase microextraction (LPME) device

Abstract

An automated LPME device for a dynamic LPME method was manufactured and its extraction efficiency was tested using spiked urine samples. The developed home-made LPME device was a programmable automated syringe dispenser to overcome deteriorating precision and difficulties in manually manipulating the plunger repeatedly. To establish the optimum parameters for benzene ethylamines, the effects of sampling volume, solvent volume, pH, salt-effect, choice of solvents, plunger speed, and number of samplings were investigated. Good repeatabilities for the extraction of mephentermine, ephedrine, methoxyphenamine, selegiline, and bupropion were obtained and the RSD values were 2.4, 1.9, 1.3, 1.6 and 1.5% at a concentration of 3 µg mL⁻¹ in spiked urine samples, respectively. The limit of detection was below 0.05 µg mL⁻¹ for the investigated drugs. This developed device for LPME analysis gave good validation results and improved convenience.