Study Of The Hydrophilic Monolithic Columns With Polyethylene Glycol

In recently decades, hydrophilic interaction liquid chromatography(HILIC), as a rival technique to reversion phase liquid chromatography(RPLC) for separating polar and hydrophilic analytes, has increasingly received attention of the researchers. However, there is still exist a large gap in application comparing to RPLC, the main reasons as follows: firstly, the hydrophilic ability of the separation materials is quite insufficient, separation and analysis of the objects is limited; secondly, the variety of hydrophilic material is thoroughly deficient, which results in less available option to the researchers; In addition to the above factors, the reason hinder its development is that the investigator has less knowledge of HILIC than RPLC and the column of HILIC is too expensive. Therefore, developing and promoting HILIC still has a lot of problems to be solved.The investigator focuses on promoting the column’s hydrophilic property and has been studied in two aspects: chemical modification and alteration the physical parameter in separating process. In this paper, we select PEG-based monolithic column which posses weak hydrophilic property as the object to carry out the following research.The researcher choose the polyethylene glycol(PEGDA,Mn=700) as monomer and fabricate monolithic column by “one-pot” process. The polysaccharide is successfully bonded on the surface of monolithic column via aqueous two phase graft polycondensation. The researcher has been prepared poly(PEGDA)-grafted-dextran and poly(PEGDA)-grafted dextran sulfate column and proceeded a series of chromatographic characterization, Polar compounds such as nucleosides, phenols, benzoic acids, amides are successfully separated on the column. The chromatography results indicate that hydrophilic property of the monolith is greatly improved.In the other hand, the investigator also tries to promote the hydrophilic property by changing the physical parameter such as temperature. The temperature can adjust freely from room temperature to-20 ℃ with a small self-made column oven. This paper systematically evaluate the retention behavior of some polar compounds such as nucleosides, phenols, benzoic acids, amides on the poly(PEGDA) column from room temperature to-20 ℃. The result forcefully indicates that hydrophily of the poly(PEGDA) monolithic column is influenced by temperature changing.The results provide a direction for the development of hydrophilic separation mode.