Urine polyamines determination using dansyl chloride derivatization in solid-phase extraction cartridges and HPLC.

The derivatization of biogenic amines such as putrescine, cadaverine, spermidine and spermine with dansyl chloride in solid phase extraction cartridges is described. Different types of filling materials were tested in order to have the highest retention of the different analytes. The best results were obtained by using C18 cartridges. The optimal conditions were: amine solution buffered at pH 12, 2 mM dansyl chloride (acetone-bicarbonate solution 20 mM (pH 9-9.5), 2 + 3 v/v) as reagent concentration, room temperature and 30 min reaction time. The developed procedure was applied to the determination of these polyamines in urine samples from healthy controls and cancer patients using HPLC with 1,7-diaminoheptane as internal standard. The concentrations ranged from 0.5 to 5 micrograms mL-1 and the detection limits were 10 ng mL-1 for all polyamines. By concentrating the urine extracts, the detection limits were improved down to 2 ng mL-1. The accuracy and the precision of the method were tested. The proposed dansylation method is advantageous with respect to solution dansylation. It improves the total analysis time, avoids high temperatures that can affect the thermal stability of the derivatives and could make possible the automation of the procedure.