A simple and rapid method for quantifying aconitines and their metabolites in whole blood by modified QuEChERS and liquid chromatography/tandem mass spectrometry (LC/MS/MS).

Aconitum contains highly toxic alkaloids such as aconitine, hypaconitine, jesaconitine, and mesaconitine. Since Aconitum ingestion causes fatal intoxication, it is important to analyze aconitines and their metabolites in the blood. In forensic toxicology, postmortem drug redistribution is known as one factor that would hamper accurate evaluation of concentrations. Therefore, it is recommended to collect multiple blood samples from various sites and compare the results to avoid miss identification of causative compounds for intoxication. In this study, we evaluated aconitines and their metabolites in postmortem blood specimens from ten sites by QuEChERS extraction and liquid chromatography-tandem mass spectrometry (LC/MS/MS). The recovery rates and matrix effects of analytes were approximately 74-80% and 94-100%, respectively. The correlation coefficients were over 0.99. The validation studies revealed that accuracies and precisions were around 97-2% (intraday) and 100-4% (interday), respectively. Finally, the concentrations of aconitine and jesaconitine were from 2.72 to 7.20 ng/mL and from 14.9 to 26.3 ng/mL, respectively. The concentrations of mesaconitine were from 0.32 to 0.88 ng/mL in four samples and detected in two. The concentrations were highest in the right atrium and lowest in the femoral vein. Our results suggest that aconitine and jesaconitne are accumulated in right atrium blood after death, and that right atrium specimen is suitable for measuring aconitine compounds in fatal intoxication cases.