SPR技术对奶粉中维生素B12检测方法的建立

Method establishment of testing vitamin B12 in milk powder based on surface plasmon resonance

中文关键词:  表面等离子共振  生物芯片  维生素B12  微生物法

英文关键词:surface plasmon resonance  biochip  vitamin B12  microbiological method

中文摘要:

      目的 利用表面等离子共振(surface plasmon resonance, SPR)技术, 建立快速定量测定牛奶中维生素B12的方法。方法 将钴胺素共价偶联到表面等离子共振芯片CM5表面, 并对竞争结合的维生素B12结合蛋白的结合浓度及芯片的再生条件进行优化, 检测芯片的稳定性。在无抗生素牛奶中添加系列质量浓度的维生素B12, 利用免疫竞争抑制原理构建标准曲线, 并对市售10个奶粉样品进行检测。结果 制备的芯片稳定, 50个循环相对标准偏差(relative standard deviation, RSD)小于10%。日间批内同一样品差异为0.54%, 该方法的检测限为0.006 μg/100 g, 回收率为92.1%~104.1%。测得的10个牛奶产品中维生素B12含量与对应商品标签值全部在标准规定的范围内。结论 所建立的方法可以在6 h内完成样品的前处理和检测, 是一种简便、快捷的定量检测方法。

英文摘要:

      Objective To establish a method of fast-testing vitamin B12 in milk by using the technique of surface plasmon resonance (SPR). Methods Vitamin B12 was covalently coupled to laboratory prepared CM5 chip to obtain vitamin chip, the optimal antibody working concentration and chip regeneration conditions were investigated. Meanwhile, the stability of vitamin chip was measured. A series of different concentrations of vitamin B12 was added to blank milk samples to construct a standard curve for vitamin B12 quantification according to the principle of competitive immune inhibition assay. Ten commercial milk samples were determined by the developed method. Results Vitamin chip displayed a good stability, and the relative standard deviation (RSD) for 50 cycles was less than 10%. The limit of detection (LOD) of vitamin B12 was 0.006 μg/100 g, and recoveries were 92.1%~104.1%. Vitamin B12 content below the required threshold level was not observed in 10 milk samples. Conclusion Less than 6 h was consumed for the determination of vitamin B12 by the developed method, this method could offer a simple and efficient approach for vitamin B12 quantification.