Digested peptides of bovine lactoferrin as the functional hydrolysates were identified by the Q-TOF tandem mass spectrometry (Q-TOF-MS) coupled with ultra performance liquid chromatograph (UPLC) and capillary electrophoresis (CE). The former (UPLC-Q-TOF-MS) identified 106 peptides while the latter (CE-Q-TOF-MS) characterized 102 peptides after comparison of peptides in terms of their molecular weight (MW), mass-to-charge ratio (m/z), and isoelectric point (pI). In addition, the hydrophilic value, net charge (q), and molecular radius (r) of the peptides were calculated, and a correlation analysis of the two methods was conducted between the retention time (RT) and r/q ratio of the peptides in order to elucidate the different separation principles of the unique peptides. It was shown that the peptides with larger hydrophilic value were beneficial to be separated by UPLC, while the peptides with larger r/q ratio were beneficial to be separated by CE. Combination of the above mentioned two complementary techniques have confidently improved the sequence coverage of lactoferrin and enhanced the identification of peptides, which makes it up to 65.8% in this study.

通过Q-TOF串联质谱（Q-TOF-MS）结合超高效液相色谱（UPLC）和毛细管电泳（CE）鉴定了牛乳铁蛋白作为功能水解产物的消化肽。前者（UPLC-Q-TOF-MS）鉴定出106个肽段，而后者（CE-Q-TOF-MS）在对肽段的分子量（MW），质荷比（ m / z）和等电点（p I）。另外，计算了肽的亲水性值，净电荷（q）和分子半径（r），并对保留时间（RT）和r / q之间的两种方法进行了相关性分析。为了阐明独特肽的不同分离原理，需要对肽的比例进行分析。结果表明，具有较大亲水性的肽有利于通过UPLC分离，而具有较大r / q比的肽有利于通过CE分离。上面提到的两种互补技术的结合无疑地提高了乳铁蛋白的序列覆盖率，并增强了肽的鉴定，在本研究中，其高达65.8％。