Determination of Trace Elements in Chinese Medicines by Neutron Activation Analysis and Spectrometry

Chen-Yeh Lin Shih-Chang Lu Lee-Chung Men

Institute of Nuclear Energy Research

Trace elements in Chinese medicines were determined by Neutron Activation Analysis (NAA),Inductively-coupled Plasma Spectrometry(ICP) and Inductively-coupled Plasma Mass Spectrometry(ICP-MS). NAA is a non-destructive method. Using epithermal neutron for activation analysis could reduce the background counts in low energy of gamma rays. As a result of getting better sensitivity for the determination of trace elements like As,Cd,Cr,Hg and Zn. The recovery and detection limits were also discussed.

Two different sample-pretreatment were studied for the methods of ICP and ICP-MS. One was mixed acid digestion and the other was sample-ashed and dissolution. The recovery of six elements of Cd,Cr,Cu,Ni,Pb and Zn was studied by using NIST Standard Reference Materials.

NAA, ICP and ICP-MS analyzed the trace elements content in 52 Chinese medicines. This database can be used as reference for the regulation of the control value of trace elements in herbs.