The Preparation And Evaluation Of A Derivatived Capillary Liquid Chromatography Monolithic Column

Capillary liquid chromatography (CLC) monolithic column have been used widely in analytical chemistry for the advantages of simple preparation, good permeability, low mobile phase and sample consumption, little pollution and easy integration with other detectors.In this study, a capillary monolithic column was preparated by in-situ polymerization of glycidyl methacrylate(GMA) and ethylene glycol dimethacrylate(EDMA) in the presence of the initatior AIBN and a binary porogen solvent composing of dodecanol and cyclohexanol, and the optimal conditions for preparing the column were established. For the first time, Lysine-Cu complexs were bonded on the surface of GMA-co-EDMA by the ring opening reaction of epoxide groups from GMA. The derivatived GMA-co-EDMA monolithic column was named as lysine-Cu derivatived monolithic column below.Several amino acids such as phenylalanine and tryptophan which can be detected by UV detector were separated on the lysine-Cu derivatived monolithic column, and the optimal separation conditions were established by examining the influences of mobile phase's pH value, ion strength and ACN concentration on the separation. The result of a further comparison experiment revealed that the mechanism for separation of the amino-acids on the column was the ligand exchange interaction between the amino acids and the immobilized cooper(â…¡). The effect of the derivation process on the polarity of GMA-co-EDMA stationary phase was also investigated, and it was demonstrated that the stationary phase possesses hydrophilicity at some extent after being derivatived in addition to the hydrophobicity due to the continuous bed of the organic polymer. Thus three anilines were separated based on the co-action of hydrophobicity and ion exchange at a low ACN concentration, and formamide and thiourea were separated by hydrophilic action in a high ACN concentration.