Preparation Of Poly (HDDA) Monolith And Investigation Of Its Chromatographic Characteristics

High performance liquid chromatography (HPLC) plays an important role inpharmaceutical analysis at present. It has been widely used in the field of life science,environmental science, and pharmaceutical analysis. Because of the advantages of goodpermeability and simple preparation, HPLC monolithic column can obtain better separationwhich makes monolithic column more important in the pharmaceutical analysis. Themonolithic column has been successfully applied in the technologies of ion-exchangechromatography, hydrophobic chromatography, affinity chromatography and volumeexclusion chromatography.A monolithic column has been prepared by traditional free radical polymerization, inwhich hexanediol diacrylate and butyl methacrylate were used as the mixed monomer,ethyleneglycol dimethacrylate as the cross linking agent, azobisisobutyronitrile as the catalyst.The conditions of polymerization were optimized. The morphology of monolithic materialswas studied by scanning electronic microscopy; the chemical groups of the monolith wereassayed by infrared spectra method and the specific surface area was determined by nitrogenadsorption-desorption. The mechanical stability and permeability of the monolith wereinvestigated by the back-pressure at several linear velocities. Finally, the monolith was used toseparate successfully three kinds of small molecules in conjunction with HPLC.Moreover, a monolithic column has been prepared by atom transfer radicalpolymerization (ATRP), in which hexanediol diacrylate and butyl methacrylate were used asthe mixed monomer, ethyleneglycol dimethacrylate as the cross linking agent, carbontetrachloride as the initiator and ferrous chloride as the catalyst. The conditions ofpolymerization were optimized. The morphology of the hybrid column was examined byScanning Electron Microscopy; the pore size distribution was determined by nitrogenadsorption-desorption; the mechanical stability and permeability of the monolith wereinvestigated by the back-pressure at several linear velocities. The result showed themonolithic column had good stability and homogeneous structure. Small molecules wereseparated successfully when the column was used as the HPLC stationary phase.