| Chelate of amino acid with trace element is suitable for absorption mechanism and characteristic of body, In which body necessary amino acid and trace element are combined. Chelate of amino acid with trace element is a new type, high effect of trace element fortificant, which have well characters and biologicalactivities. Glycine is the smallest amino acid, and the chelate of glycine with trace element also has the smallest molecular weight, so it is more suitable to body. In this article, ferrous glycinate was synthesized using ferrous carbonate and glycine as raw materials, zinc glycinate was synthesized using basic zinc carbonate and glycine as raw materials.The preparation of ferrous glycinate was firstly studied. By single factor experiments, the synthesis technology was confirmed. The optimal reaction condition was as follows: pH was between 5.5～6, the amount of complex antioxidants was 10％of the amount of glycine, the molar ratio of glycine to ferrous was 2:1, and water bath temperature was 80℃. The filtrate was treated with organic solvent and the ferrous glycinate was precipitated in organic solvent. Consequently, the chelate can be purified and analyzed by common chemical method. With this condition, ferrous glycinate was obtained, the content of ferrous account for 85％of total iron content, the yield was 87.21％, the chelated ratio was 86.95％. Oxidation stability of ferrous glycinate was significantly better than that of FeCl2 by the storing experiment. Hydrolyzing stability test showed that ferrous glycinate keep no hydrolyzation in water. On the contrary, FeSO4 solution hydrolyzed very fast and formed deposit of Fe(OH)2. whereafter oxidated to be Fe(OH)3, finally, turned to be Fe2O3 deposit. The infrared spectrometry of ferrous glycinate showed that there were no characteristic absorption of free glycine and it exists with a chelating compound structure; the thermogravimetric and differential thermal analyses showed that there was one molecule water in the chelate. Its molar conductance was 34.0Scm2/mol, stabilization constant was 5.08×105.Then the preparation of zinc glycinate was studied. The reasonable reaction conditions were that: the molar ratio of basic zinc carbonate to glycine was 0.5:1, water bath temperature was 90℃, time was 6h, pH was 6.5, The filtrate was treated with organic solvent and the zinc glycinate was precipitated in organic solvent. Consequently, the chelate can be purified and analyzed by common chemical method. With this condition, zinc glycinate was obtained, the yield was over 95％. After purification, composition and structure of the complex was characterized by some analysis methods, such as elementary analysis, infrared spectrum, ultraviolet spectrum, thermogravimetric and differential thermal analyses and powder diffraction. The result indicate there was no dissociative glycine in the product, the chelate was a molecule compound with one molecule water, the molecular formula was Zn(NH2CH2COO)2·H2O. its molar conductance was 20.1Scm2/mol, stabilization constant was 2.29×105 and chelated ratio was 100％±1％.
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