商品化酪蛋白磷酸肽中通用型标记肽的筛选及其在婴幼儿配方奶粉中应用

Selection of universal marker peptides from commercial casein phosphopeptide and quantification analysis applications in infant formula powder

中文关键词:  酪蛋白磷酸肽  通用型标记肽  液相色谱-串联质谱法  筛选  定量  婴幼儿配方奶粉

英文关键词:casein phosphopeptides  universal marker peptide  liquid chromatography-tandem mass spectrometry  selection  quantitative  infant formula powder

中文摘要:

      目的 对4种常见的商品化酪蛋白磷酸肽(casein phosphopeptides, CPP)的多肽组成进行鉴定, 筛选通用型标记肽, 并且应用于婴幼儿配方奶粉中CPP含量的定量检测。方法 采用液相色谱-串联飞行时间质谱法对多肽进行鉴定和筛选; 采用同位素稀释液相色谱-串联质谱技术, 建立婴幼儿配方奶粉中CPP含量的检测方法。结果 所筛选获得的多肽VLPVPQK普遍存在于4种商品化CPP中, 定量检测方法的标准曲线线性r2>0.99, 平均回收率在99.0%~101.5%之间, 批间精密度在3.8%~5.7%之间, 方法精密度在2.0%~7.6%之间, 符合检测要求。结论 该通用型标记肽普遍适用于中国市场上常见的商品化酪蛋白磷酸肽, 适合婴幼儿配方奶粉企业用于产品质量控制, 方法简单高效, 可应用于常规理化实验室。

英文摘要:

      Objective To identify peptides from four commercial casein phosphopeptide (CPP) and select a peptide as universal marker, which can be used for the quantification of CPPs in infant formula. Methods The identification and selection of peptide were carried out using liquid chromatography-tandem time–of-flight mass spectrometry. The method of quantification CPP in infant formula was established by isotope dilution and liquid chromatography-tandem quadruple mass spectrometry. Results The selected peptide VLPVPQK was universally present in 4 commercial CPPs. The standard curve of the quantitative detection method had linearity r2>0.99, the average recovery rate was between 99.0%-101.5%, the inter-assay precision ranged from 3.8% to 5.7%, and the precision of the method ranged from 2.0% to 7.6%, which met the testing requirements. Conclusions This universal marker peptide is generally applicable to the commercial CPPs in the Chinese market. Because of its simplicity and efficiency, it is suitable for the product quality control of infant formula enterprises.