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Hydroxy monolith precursor for the preparation of organic polymer monolithic columns by post-polymerization modification with various surface retentive ligands for capillary electrochromatography and high performance liquid chromatography

Khadka, Shantipriya
The objective of this dissertation involved furthering the development of the concept of post-polymerization modification by introducing a novel poly(HEMA-co-PETA) precursor monolithic column to which various types of ligands were chemically grafted. Three different types of monolithic stationary phases were fabricated from the above single precursor monolithic column including those with surface modified 1,2-epoxyalkane and 1-isocyanato-octadecane yielding aliphatic nonpolar surfaces, which were evaluated in the RPC mode of separation. Similarly, the immobilization of 2-biphenylylglycidylether led to the generation of aromatic nonpolar surface, which was also assessed in RPC using CEC and HPLC techniques. On the other hand, glycerol, ethylenediamine, diethylenetriamine and triethylenetetramine were immobilized on the same precursor column yielding polar monolithic stationary -phases, which were studied in hydrophilic interaction capillary electrochromatography (HI-CEC). The studies described in this dissertation have demonstrated the versatility of a hydroxy monolithic column, which can be used as a precursor or a parent monolith for the fabrication of various types of stationary phases. By using a simple and well-known epoxy ring-opening reaction, various types of ligands were immobilized on the precursor surface, a fact that demonstrated that a desired stationary phase could be tailored as required.