Simultaneous determination of three aconitum alkaloids in urine by LC-MS-MS.

A sensitive method has been developed for the identification and quantification of the toxic alkaloids yunaconitine, crassicauline A, and foresaconitine in urine specimens. After solid-phase extraction using Oasis MCX cartridges, the extracts were analyzed by LC-MS-MS. The limit of detection is 0.03 ng/mL urine for yunaconitine and 0.05 ng/mL urine for crassicauline A and foresaconitine; the limit of quantitation is 0.15 ng/mL urine for yunaconitine and 0.20 ng/mL urine for crassicauline A and foresaconitine. The method was employed in the analysis of the urine of a 55-year-old male who died after ingestion of herbal medicine powder made from the roots of aconite. Yunaconitine, crassicauline A and foresaconitine were identified in the urine. Crassicauline A and foresaconitine were thus identified in a biological specimen for the first time.