Synthesis and characterization of bisphenol-A imprinted polymer as a selective recognition receptor

Molecularly imprinted polymers (MIPs) are currently used to provide selectivity in chemical sensors. In this context, a non-covalent bisphenol-A (BPA)-imprinted polymer using 4-vinylpyridine (4-Vpy) as the functional monomer, ethylene glycol dimethacrylate (EGDMA) as crosslinker and a low volatile solvent, triethylene glycol dimethyl ether (TRIGLYME), in combination with a non-reactive linear polymer, poly (vinyl acetate) (PVAc), as porogen, was synthesized with a simple polymerization procedure. Batch rebinding experiments were carried out to evaluate the binding and selectivity properties of the BPA-MIP. The experimental adsorption isotherms were fitted and a heterogeneous distribution of the binding sites was found. The selectivity of MIP demonstrated higher affinity for target BPA and BPA-analogues over other common water pollutants. The adsorption kinetics followed the pseudo-second-order kinetic model so that the specific adsorption in the imprinted cavities by two strong hydrogen bonds could be described as a chemisorption process. The diffusion mechanism was determined by the intra-particle diffusion and Boyd models, both of them revealing that the adsorption was mainly governed by intra-particle diffusion. MIP was shown to be promising for regeneration without significant loss in adsorption capacity.

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► The binding affinity of BPA-MIP high affinity sites is very resilient.
► A low volatile solvent and a non-reactive linear polymer are a good porogen system.
► Selectivity recognition is achieved for aqueous samples.
► The limiting step of the adsorption process is carried out in the imprinted cavities.
► The adsorption capacity is kept when the sorbent is regenerated.