Development of molecularly imprinted membranes for selective recognition of primary amines in organic medium

Imprinting technique, coupled with membrane technology was used in order to prepare solvent resistant molecularly imprinted membranes with controlled specificity for the primary aromatic amine 4,4′-methylendianiline. Polyacrylonitrile and its different copolymers such as Poly(acrylonitrile-co-acrylic acid), Poly(acrylonitrile-co-methacrylic acid) and Poly(acrylonitrile-co-itaconic acid), were selected as materials to prepare the membranes. The different polymers, were synthesized by the water-phase precipitation polymerization method and membranes were prepared via the phase inversion technique. Their recognition properties and separation behaviour for target molecule and other structural analogue were investigated performing binding experiments in IPA. Results showed that all imprinted membranes specifically recognize the template in different extent. Imprinted membranes prepared with Poly(acrylonitrile-co-acrylic acid) were competitive with those prepared using the other two copolymers and exhibited the highest specific binding capacity towards the template (2.6 μmol/gmemb). In addition, they were selective with respect to the other primary amine aniline and 4,4′-ethylendianiline. On the contrary, Polyacrylonitrile and blank membranes, showed only a non-specific binding.

► We developed novel imprinted membranes for specific separations in organic solvent.
► Acrylonitrile copolymers containing acidic groups were the membrane forming material.
► The target molecule was the primary aromatic amine 4,4′-methylendianiline.
► In rebinding tests membranes exhibited good recognition properties and selectivity.