Novel hybrid molecularly imprinted membranes for targeted 4,4′-methylendianiline

• PVDF scaffold was hybridized with a polymer imprinted with 4,4′-methylendianiline.
• The novel imprinted membranes exhibited specific recognition in organic environment.
• Theoretical study provided the H-bond energies of the pre-polymerization complexes.

Organic solvent resistant hybrid imprinted membranes were prepared by dispersing an imprinted polymer in polyvinylidene fluoride matrix. Acrylonitrile, acrylic acid and ethylene glycol dimethacrylate were used to synthesize the imprinted polymer. The genotoxin 4,4′-methylendianiline was the template. Membranes prepared via non-solvent induced phase separation were characterized by water, methanol and isopropanol permeate flux measurements and scanning electron microscopy. Recognition properties of membranes were evaluated by performing binding experiments with the template and its structural analogue 4,4′-ethylendianiline in isopropanol. Non-imprinted membranes were also prepared and tested. Membrane containing 33 wt.% of imprinted polymer showed the highest binding capacity (7.5 μmol/gmemb) while the corresponding non-imprinted membrane bounded 4.4 μmol/gmemb. This membrane exhibited a selectivity factor of 1.82 towards 4,4′-ethylendianiline.Computational molecular modelling was also performed. The binding energies of the hydrogen bonds present in the pre-polymerization complexes, were calculated using a quantum mechanical approach in the frame of Density Functional Theory. Among the H-bonds formed between the different components of the reaction mixture, that one formed by the amino group of 4,4′-methylendianiline with the hydroxyl of the acrylic acid in water is the most stable. Furthermore, the acid group of a single monomer interacts more effectively with the template than the same group present in a polymeric fragment. In vacuum, this behaviour is the inverse.