Molecular imprinted membranes prepared by phase inversion of polyacrylonitrile copolymers containing carboxylic acid groups

摘要

Phase inversion of polyacrylonitrile copolymers containing carboxylic acid groups is utilized to prepare molecular imprinted membranes for theophylline (THO). The copolymer cast colution of dimethyl-sulfoxide (DMSO) with the THO template is immersed in water which causes the polymer including the template to coagulate in the nonsolvent. After removal of the template from the solidified copolymer membrane, high selectivity for rebinding of THO is observed compared to binding of the structurally related molecule caffeine. The molecular imprinting process was affected by the template concentration in the DMSO cast solution, the coagulation conditions, and the carboxylic acid content in the copolymer. High binding selectivity of the THO solute by the THO-imprinted copolymer membrane arises from the formation of imprinted sites in which free OH groups of the carboxylic acid units form hydrogen bonds with the THO.