【作者】 许灵艳；

【导师】 梁鑫淼； 金郁；

【作者基本信息】 华东理工大学 ， 制药工程与技术， 2011， 硕士

【摘要】 氧化钛具有高的机械强度、好的化学稳定性和热稳定性,可以作为一种良好的色谱填料。本论文采用自制的氧化钛作为色谱填料,首先采用不同化合物作为探针分子,分别考察了有机相含量、缓冲盐和pH对酸性化合物、碱性化合物、黄酮苷元和黄酮苷类化合物保留行为的影响,对其色谱性能进行了较为系统的评价。通过对不同类化合物在氧化钛色谱柱上的保留机理和保留规律的讨论,发现黄酮苷类在氧化钛柱上的保留很强,且和黄酮类化合物在氧化钛柱上的保留差异很大,推测是因为黄酮苷类中糖配基相邻的两个羟基与氧化钛表面的路易斯酸位点有配体交换作用。因此采用氧化钛作为基体分散固相萃取的填料选择性地富集降香中微量的黄酮苷类化合物。用液质联用的方法对富集的黄酮苷进行表征,表征出8个黄酮碳苷类化合物。为了验证糖苷类化合物在氧化钛上的保留机理,选择邻二苯酚作为探针物质,考察了其在不同流动相条件下的保留情况,间接验证了推测的机理。利用邻二酚羟基的配体交换作用,在氧化钛表面涂覆邻二苯酚以覆盖其表面的路易斯酸性位点,对氧化钛色谱柱进行改性,覆盖密度约为0.36μmol/m2。氧化钛表面涂覆邻二苯酚后,对其进行了基本的色谱性能评价。利用该机理可以对四环素进行富集。更多还原

【Abstract】 Titania with higher mechanical, chemical and thermal stability, which can be used as an stationary phase. In this paper, titania produced in our laboratory was used for stationary phase of high performance liquid chromatography. At first its chromatographic properties have been systematically evaluated, that is, the effect of the mobile phase composition, different buffer and pH on the retention of acidic compounds, basic compounds, flavonoids and flavonoid glycosides on the titania column was examined, respectively.The retention mechanism and pattern was discussed according to the characteriztion result, it was found that the retention of flavonoid glycosides on the titania column was very strong, and the difference of retention between flavonoid and flavonoid glycosides is obvious. It is deduced that it may be due to the ligand-exchange interaction between the ortho hydroxyl groups of sugar glycoside and the strong Lewis acid sites on the surface of titania. Therefore trace flavonoid glycosides in Lignum Dalbergia Odorifera will be separated and enriched by matrix solid-phase dispersion (MSPD) using titania. At last enriched flavonoid glycosides were further analyzed by UPLC-MS/MS, eight flavonoid glycosides were proved as C-glycosyl flavonoid according to their fragmentation in MS2.In order to prove the retention mechanism of flavonoid glycosides on titania column, o-dihydroxybenzene which has the UV absorption was selected as probe compound, its retention under different condition was studied, the result proved our hypothesis indirectly.O-dihydroxybenzene was coated on a titania column to block the Lewis acid sites on the surface by the ligand-exchange interaction, the loading density was about 0.36μmol/m2. The basic chromatographic characteristics of the titania column modified by o- dihydroxybenzene were investigated. Tetracycline was enriched by the same mechanism.更多还原