A simple and rapid method for analysis of Aconitum alkaloids in serum and urine using liquid chromatography electrospray ionization mass spectrometry

Abstract

A simple and rapid method for determination of Aconitum alkaloids, aconitine, mesaconitine, hypaconitine and jesaconitine, in serum and urine samples has been developed using liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) combined with Extrelut^® column extraction. The protonated molecular ions were observed as base peaks of these alkaloids. The alkaloids were separated on an XTerra^® RP18 column with isocratic elution with a solvent mixture of 0.1% (v/v) formic acid in acetonitrile and 0.1% (v/v) formic acid in aqueous solution (24:76, v/v) using selective ion monitoring of protonated molecular ions. The calibration curves of the alkaloids in serum and urine were linear in the range of 5-200 pg per injection, and the detection limits of the alkaloids were 1 pg per injection (S/N=3). The recovery rates of the alkaloids ranged from 83.7% to 89.0% in serum and from 85.6% to 89.9% in urine. The inter-day precision and intra-day precision were acceptable. This method of analysis can be used for identification and quantitative determination of Aconitum alkaloids in cases of aconite poisoning and will be useful for investigating the pharmacokinetics of aconite substances in humans. In addition, it is simple and rapid and should therefore be useful in emergency medicine, in which quick and accurate test results are required.