Determination and primary speciation analysis of metal elements in rhubarb roots by ICP-MS

The metal elements in rhubarb roots were separated into soluble state and suspension state by 0.45 μm membrane filter based on traditional analytical flowchart program. The rhubarb roots at different producing areas and the decoction of rhubarb roots were pretreated by wet digestion, and then the metal elements were determined by ICP-MS analysis. The results indicate that there is obvious difference in the contents of metal elements between the different places. The dissolved rate of metal elements was low in the decoction of rhubarb, and the metal elements mainly existed in organic state with low water solubility. The determined metal elements mainly existed in soluble state, and their contents in soluble state are more than 50%. The determination and primary speciation analysis of the metal elements in rhubarb roots can provide useful information about bioavailability and pharmacological functions of rhubarb roots.