| 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.
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