EDTA络合滴定法测定脑膜炎球菌多糖疫苗原液中的残留钙离子

Determination of residual content for calcium ion in meningococcal polysaccharide vaccine bulk by compleximetry

目的建立EDTA络合滴定法,测定A群C群脑膜炎球菌多糖疫苗中残留钙离子含量,为疫苗的质量控制提供依据。方法在p H>12的条件下,用乙二胺四乙酸(ethylenediaminetetraacetic acid,EDTA)滴定液测定C群脑膜炎球菌多糖疫苗原液中的残留钙离子,并对该方法的线性范围、准确性和重复性进行验证及初步应用。结果钙离子质量浓度在0.200 2~1.602 0 mg/m L范围内,钙离子含量与消耗滴定液的体积呈现良好的线性关系,r>0.99;在对照实验碳酸钙和无水氯化钙中,钙离子的回收率分别为100.9%和100.3%,相对标准偏差(RSD)分别为0.35%和0.21%;C群多糖原液加标回收实验中钙离子的回收率为99.7%~101.2%,RSD≤0.77%;测定6批C群脑膜炎球菌多糖原液中的钙离子浓度,RSD均≤5.6%。结论建立的EDTA络合滴定法简便、快速、准确,适用于A群C群多糖疫苗原液中钙离子含量的快速测定。

Objective To set up a EDTA compleximetry in determination of residual calcium ion content in group A and C meningococcal polysaccharide vaccine,so as to provide a basis for quality control of the related vaccine. Methods Under the condition of p H 12,by using EDTA（ ethylenediaminetetraacetic acid） solution in titration of residual calcium ion content in bulk of group C polysaccharide vaccine. The method was verified for linearity,accuracy and reproducibility and a preliminary application was performed in the tested process. Results The test showed a good linear relationship between the titrated volume and calcium content,in a range of calcium from 0.200 2 mg/m L to 1.602 0 mg/m L,with r0.99. And calcium recovery rates were 100.9% and 100.3%,respectively,in the control tests for calcium carbonate and anhydrous calcium chloride,with RSD（ relative standard deviation） for 0.35% and 0.21%. The sample were directly titrated by EDTA for three concentration levels,which showed recovery rates obtained between 99.7% and 101.2%,and the RSD were ≤5.6% for calcium ion in tested 6 batches of the bulks. Conclusion The method was simple,fast and accurate,which may be used as a rapid test in determination of calcium ion content in bulk of group A and group C meningococcal polysaccharide vaccine.