Comparison of liquid chromatography-high-resolution tandem mass spectrometry (MS) and multi-stage mass spectrometry (MS) for screening toxic natural products.

BACKGROUND

Liquid chromatography-high-resolution mass spectrometry (LC-HR-MS) has emerged as a powerful analytical technology for compound screening in clinical toxicology. To evaluate the potential of LC-HR-MS in detecting toxic natural products, a spectral library of 85 natural products (79 alkaloids) that contains both MS and MS mass spectra was constructed and used to identify the natural products. Samples were analyzed using an LC-HR-MS method and the generated data were matched to the spectral library to identify the natural products.

METHODS

To test the performance of the LC-HR-MS method in different sample matrices, the 85 natural product standards were divided into three groups to separate structural isomers and avoid ion suppression effects caused by co-elution of multiple analytes. The grouped analytes were spiked into drug-free serum and drug-free urine to produce contrived clinical samples.

RESULTS

The compound identification results of the 85 natural products in urine and serum samples were obtained. The match scores using both MS and MS mass spectra and those using only MS mass spectra were compared at 10 different analyte concentrations. The two types of data analysis provided identical identification results for the majority of the analytes (96% in serum, 92% in urine), whereas, for the remaining analytes, the MS-MS tree data analysis had better performance in identifying them at lower concentrations.

CONCLUSION

This study shows that in comparison to LC-HR-MS (MS), LC-HR-MS can increase the performance in identification of a small group of the toxic natural products tested in serum and urine specimens.