Development of novel hybrid imprinted membranes for selective recovery of theophylline

A theophylline-binding polymer was synthesized utilizing the bulk polymerization technique. Methacrylic acid, ethylene glycol dimethacrylate, 2,2'-azoisobutyronitrile and chloroform were used to synthesize the imprinted polymer. Theophylline was employed as template. The obtained polymer powder were dispersed in the modified poly(ether ether ketone) (PEEK-WC) polymer solution for preparing hybrid imprinted membranes via the phase inversion technique. Membranes containing the non-imprinted polymer were also prepared and used as reference. For evaluating the recognition properties of polymers and membranes re-binding experiments, with the template and its structural homologue caffeine, were carried out. The binding capacity of MIP towards the template was 1.18 mu mol/g(p) and the theophylline/caffeine selectivity factor was 3.2. All the imprinted membranes exhibited good recognition properties compared with blank membranes, which only showed a poor non-specific binding. The membrane containing 30 wt% of the imprinted polymer exhibited the highest binding capacity (10.97 mu mol/g(memb)), and a theophylline/caffeine selectivity factor of 71.42.