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抗坏血酸与自由钢(Ⅱ)及其多胺螯合物不发生直接的氧化还原反应。铜(Ⅱ)与抗坏血酸有络合作用。螯合齿数大于2的铜(Ⅱ)-多胺螯合物对抗坏血酸的有氧氧化无催化活性。当配位数为2时,铜(Ⅱ)-乙二胺的1:1螯合物的催化反应符合酶催化动力学。自由铜(Ⅱ)催化反应对铜(Ⅱ)及抗坏血酸均显一级。实验结果说明钢(Ⅱ)在催化抗坏血酸有氧氧化时,只能有2个配位位置被占据。其它位置必须是空位或容易被取代。实验事实支持三元络合物形成的机制。
Ascorbic acid does not undergo a direct redox reaction with free steel (II) and its polyamine chelates. Copper (Ⅱ) complexed with ascorbic acid. Cu (II) -polyamine chelates with more than 2 chelates have no catalytic activity for the oxidation of ascorbic acid. When the coordination number is 2, the catalytic reaction of 1: 1 chelate of copper (II) -ethylenediamine conforms to the enzyme catalytic kinetics. Free copper (Ⅱ) catalysis reacted to copper (Ⅱ) and ascorbic acid obviously. Experimental results show that steel (Ⅱ) can catalyze the oxidation of ascorbic acid only two coordination sites are occupied. Other locations must be vacant or easily replaced. Experimental facts support the formation of ternary complexes.