Analysis of aconitum alkaloids by means of gas chromatography/selected ion monitoring.

Abstract

A gas chromatography/selected ion monitoring (GC/SIM) method for the simultaneous determination of aconitum alkaloids such as aconitine, mesaconitine and hypaconitine has been developed. Aconitum alkaloids were converted to their TMS ether derivatives by treatment with N, O-bis (trimethylsilyl) trifluoroacetamide in pyridine at room temperature. The gas chromatograms of reaction products showed in each case a well-resolved doublet consisting of a major (>70%) and a minor components, when analyzed using a 5%-phenylmethylsilicone cross-linked fused silica capillary column. These alkaloid derivatives gave simplified mass spectra with a base peak at m/z 698 for aconitine, m/z 684 for mesaconitine and m/z 596 for hypaconitine. When GC/SIM of aconitine was carried out under monitoring of the ion at m/z 698, detection limit was 10 picograms with signal-to-noise ratio of greater than 10. Linearity was obtained over a range from at least 10 to 1000pg. Similar results were obtained with another alkaloids. The use of this method for the measurement of aconitum alkaloids in biological fluids is described.