Accurate Determination Of Zinc And Selenium Isotope By Inductively Coupled Plasma Mass Spectrometry

Zinc and selenium are necessary nutrient trace element in the life activity of human and animals which are extensively distributing everywhere in the body. They exert significantly influence on growth and develop, body repairing, body immunity and intelligence quotient.In present dissertation, experimental studies of separate techniques of zinc and selenium for matrix analysis with isotope dilution mass spectrometry (IDMS) were carried out. The main achievements obtained in this research are: (1) The separation of zinc with anion exchange resin. Separation conditions such as separation efficiency and column height were discussed. The recovery of zinc is above 96%. Combined with IDMS, this method was applied in determination zinc in soybean, human serum and bovine liver. The results are accurate and credible. (2) The separation of selenium isotope with sulphydryl cotton. Separate conditions such as efficiency and exchange capacity were discussed. The recovery of selenium is above 92%. Standard solution of different isotopic abundance were successfully separated. Combined with IDMS, this method was applied in determination selenium in human serum and bovine liver. The result is in the range of uncertainty of standard value. These separate techniques can also be applicated in separation of selenium isotope in compound matrix.This dissertation also refered to the research of isotopic standard, And the separate technique of zinc was applied and buoyancy correction was considered. Two highly purified and high concentrated isotope were blended to prepare isotope standard samples by gravimetry using exact balance. According to measurement of isotope standards by mass spectrometry, the correction factor of system error of mass spectrometry can be confirmed. The method is accepted by IUPAC to obtain accurate isotopic abundance of samples.