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A novel porous monolithic column was prepared by in situ free-radical polymerization in a 50 mm 9 4.6 mm i.d. stainless steel column at 60°C, which was in the presence of 2,2 0 -azobisisobutyronitrile (AIBN) as initiator, with N-isopropylacrylamide (NIPAAm) and methacrylic acid (MAA) as monomers, ethylene dimethacrylate (EDMA) as crosslinker, methanol and dodecanol as a porogenic solvent. The micrographs of monolithic column were characterized by scanning electron microscopy (SEM) and pore size distribution was determined by mercury intrusion porosimetry. The pressure drop across the columns was measured as a function of flow rate using water and methanol. The result showed that the monolithic columns had an excellent permeability and a high mechanical stability. Moreover, the influence of several parameters which were column temperature, mobile phase composition and flow rate was investigated in the separation of mixtures of nifedipine and nisoldipine. In addition, the effects of type and concentration of buffer on the elution of human plasma protein were investigated. The results showed that a better peak shape was obtained at higher temperature and larger flow rate on the monolithic column.

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