Rapid detection of pesticide residues in Chinese herbal medicines by molecularly imprinted membrane electrospray ionization mass spectrometry

Chinese herbal medicines (CHMs) play an increasingly important role in the field of medicine and affects public health in the world. Although more and more strict has been employed to ensure the quality and safety of CHMs, pesticide residues in CHMs remain a serious issue and are the bottleneck for the global development of CHMs. In this work, we applied molecularly imprinted membrane electrospray mass spectrometry (MIM-ESI MS) for rapid detecting 4 classes of pesticide residues in CHMs, including organophosphorus (OPP), carbamates, pyrethroids and neonicotinoids in CHMs. Compared with our previous ambient ionization method MESI, MIM-ESI is capable of achieving a ～50-fold increase in the detection limit of conventional analytical methods owing to the specificity recognition and unique enrichment of MIM. The optimal experimental conditions were determined, and the method was further validated for its sensitivity and specificity. Our data showed that MIM-ESI MS is applicable for the direct quantitation of pesticide residues in CHMs. This detection technology may help to ensure the quality of CHMs in the future.