A novel approach for fast and simple determination pyrrolizidine alkaloids in herbs by ultrasound-assisted dispersive solid phase extraction method coupled to liquid chromatography–tandem mass spectrometry

Abstract

Pyrrolizidine alkaloids (PAs) are secondary plant metabolites witch can contaminate food, especially herbs. Due to the fact that alkaloids have a strong adverse effect on human health, it is necessary to use sensitive and selective detection methods. In present study a modified method based on LC–MS/MS was developed and validated for the simultaneous determination of thirty pyrrolizidine alkaloids and their corresponding N-oxides (PANOs) in herbs samples. Sample extraction was based on ultrasound-assisted dispersive solid phase extraction and clean-up using graphene. Method validation showed that the proposed method hold good recoveries (61–128 %) for PAs/PANOs with RSD <15 %. Limits of quantification has been set at 1 μg kg−1 level for all targeted alkaloids. The optimized method yielded a small matrix effect (-20–20 %) for most PAs/PANOs. The uncertainty associated with the analytical method was not higher than 38 %. The method is operationally simple, time-saving, and can be applied to the analysis of real herb samples.