Abstract:A method based on high-resolution mass spectrometry library and characteristic component diagnostic ratio was established for identifying illegally added epimedium in food. A high resolution mass spectrometry library of six characteristic components of epimedium was constructed by high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (HPLC-TOF-MS) for preliminary screening. Simulated wine, substitute tea and drink samples were prepared using Chinese medicinal materials of epimedium obtained from different origins and picking times. A liquid chromatography analysis method was established for the characteristic components of epimedium in three different matrices. The characteristic component peak area diagnostic ratios, DR1 (epimedin A/ epimedin B), DR3 (epimedin A/ icariin) and DR7 (epimedin B/ icariin), which were less affected by the origin, picking time and processing technology, with no significant differences among different matrix groups, were selected and combined to draw box plots. . Then, the non-abnormal value ranges of diagnostic ratios were determined to be 0.60~0.96, 0.26~0.64 and 0.35~0.91, respectively, which were used as identification indicators. The actual samples of prepared wine, substitute tea and drink were analysed. The prepared wine samples of one batch matched with the high-resolution mass spectrometry library of the six characteristic components of epimedium. The diagnostic ratios of the three characteristic components DR1, DR3 and DR7 were 0.73, 0.28 and 0.38, respectively, which were all within the specified range, inferring that epimedium-containing Chinese medicinal materials had been added to the prepared wine samples. The method is accurate, fast and stable, and can quickly identify the illegal addition of epimedium to food and provide technical support for cracking down on the illegally added epimedium in food.
