本文通过模拟动物胃肠道内pH的环境来处理螯合物样品,使螯合物样品中的非络合态以及较小结合力的络合态金属元素以离子状态存在,再通过凝胶过滤法对螯合态和游离态的金属离子进行分离,测定各组分中金属元素的含量,即可计算出样品有效螫合率.具体测定方法为:样品溶解处理时pH调至3.0,离心后的上清液pH调回中性,上柱洗脱时碱性洗脱液为pH9.0的Clark - lubs缓冲液,酸性洗脱液为pH2.0HCl溶液.该方法得到的结果变异系数在2％～2.5％之间,精密度较好.%In this paper, samples were chelated in simulating animal gastrointestinal pH environment. The non -che-lating compounds as well as the smaller binding metal elements complex were existed in ionic state. Then the chelated complex and free metal ions were separated by gel filtration. The metal element content determined chelation rate. The procedure was: dissolving the samples at pH 3. 0 and neutralized pH of the supernatant after centrifugation. The samples were then eluted in Gel column, Clark - lubs buffer with pH 9. 0 was selected as alkaline eluent and pH 2.0 HCI solution was used as acidic eluent. The coefficient of variation of the method was between 2% and 2.5%. The method had a better precision.
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