试剂盒法快速检测婴幼儿乳粉中叶酸含量

目的 建立试剂盒法快速检测婴幼儿乳粉中叶酸的含量。方法 以Tris缓冲液稀释样品, 加入冻干的干酪乳杆菌测试菌球, 采用Costar 3599细胞培养板培养, 使用酶标仪测定结果。并同时检测了28批次婴幼儿乳粉叶酸的含量。结果 本试剂盒方法回收率为95%~105%, 定量检测限为0.050 ng/mL, 日间精密度为0.6%, 日内精密度为0.7%。采用试剂盒方法与GB 5413.16-2010试管法同时检测28批次婴幼儿乳粉中叶酸的含量, 检测结果无显著性差异(P=0.598), 乳粉中叶酸含量的合格率为100%。结论 该方法操作简单, 灵敏度高, 重现性好, 可用于测定婴幼儿乳粉中叶酸的含量。

Rapid determination of folic acid in infant formula by reagent kit method

Objective To establish a method for rapid determination of folic acid in infant formula by reagent kit. Methods Samples were diluted with Tris buffer, the freeze-dried test fungus ball of Lactobacillus caserta spp. rhamnosus was added, cultured together in the Costar 3599 cell culture plate, and measured finally by microplate reader. The content of folic acid in 28 batches of infant milk powder was detected simultaneously. Results The recoveries of the reagent kit methods were in the range of 95%-105%, with the detection limit of 0.050 ng/mL. The inter-day precision was 0.6% and intra-day precision was 0.7%. Tube method in GB 5413.16-2010 and the reagent kit method were used for the detection of 28 batches of infant formula simultaneously, there was no significant difference in the test results (P=0.598). The qualified rate of folic acid content in milk powder was 100%. Conclusion The reagent kit method is simple, sensitive and reliable, which can be used for the determination of folic acid in infant formula.