Quadrupole Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was used to determine lead (Pb) isotope ratios in Dan-shen, a type of herb used in Traditional Chinese Medicines (TCM), and in water and soil samples all taken from the same geographical location.
This document is an application note describing a scientific study that utilized Quadrupole Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to analyze lead isotope ratios in Dan-shen, a traditional Chinese medicine herb. The study aimed to verify if isotopic measurements could serve as a reliable method for fingerprinting the geographical origin of the herb, which is critical for ensuring its medicinal effectiveness. The research compared results from Dan-shen samples, soil, and water collected from various locations in China.
| RF power | 1250 W |
|---|---|
| Carrier Gas flow rate | 0.4 L/min |
| Make-up Gas flow rate | 0.9 mL/min |
| Sample uptake rate | about 50 uL/min |
| Integration time for 204Pb | 20sec |
| Integration time for 206Pb | 10sec |
| Integration time for 207Pb | 10sec |
| Integration time for 208Pb | 5 sec |
An Agilent 7500i ICP-MS fitted with a PFA micro flow nebulizer was used throughout the study.
SRM981 from the National Institute of Standards & Technology was used for mass bias correction.
Yes, the results show that it is possible to distinguish Dan-shen samples originating from different geographical areas using Pb isotope ratio measurements.