Preparation of phenylalanine imprinted polymer by the sol–gel transition method

A phenylalanine (Phe) imprinted polymer was prepared by the wet-phase inversion and sol–gel transition method to endow a copolymer matrix with a large uptake capacity of template molecules and prominent adsorption selectivity at the high concentration of the racemate solution. A copolymer bead prepared by wet-phase inversion was shrunken in a hydrochloric acid solution containing a large amount of template molecules after swelling in a sodium hydroxide solution. Template molecules were effectively implanted in the polymer matrix during shrinking after swelling. The adsorption selectivities of Phe-imprinted copolymer bead were 2.1 and 1.33 at 1 g and 10 g Phe/l racemate solution, respectively, and the Phe uptake capacity reached about 1 g Phe/g dry weight of the copolymer. The adsorption selectivity of the copolymer was retained after five batches of adsorption/desorption in 1 g Phe/l solution composed of 5% d-Phe and 95% l-Phe.