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Portable biomimetic sensor devices for the express control of phenols content in water were developed. The synthetic binding sites mimicking active site of the enzyme tyrosinase were formed in the structure of free-standing molecularly imprinted polymer membranes. Molecularly imprinted polymer membranes with the catalytic activity were obtained by co-polymerization of the complex Cu(II)-catechol-urocanic acid ethyl ester with (tri)ethyleneglycoldimethacrylate, and oligourethaneacrylate. Addition of the elastic component oligourethaneacrylate provided formation of the highly cross-linked polymer with the catalytic activity in a form of thin, flexible, and mechanically stable membrane. High accessibility of the artificial catalytic sites for the interaction with the analyzed phenol molecules was achieved due to addition of linear polymer (polyethyleneglycol Mw 20,000) to the initial monomer mixture before the polymerization. As a result, typical semi-interpenetrating polymer networks (semi-IPNs) were formed. The cross-linked component of the semi-IPN was represented by the highly cross-linked catalytic molecularly imprinted polymer, while the linear one was represented by polyethyleneglycol Mw 20,000. Extraction of the linear polymer from the fully formed semi-IPN resulted in formation of large pores in the membranes' structure. Concentration of phenols in the analyzed samples was detected using universal portable device oxymeter with the oxygen electrode in a close contact with the catalytic molecularly imprinted polymer membrane as a transducer. The detection limit of phenols detection using the developed sensor system based on polymers-biomimics with the optimized composition comprised 0.063 mM, while the linear range of the sensor comprised 0.063-1 mM. The working characteristics of the portable sensor devices were investigated. Storage stability of sensor systems at room temperature comprised 12 months (87%). As compared to traditional methods of phenols detection the developed sensor system is characterized by simplicity of operation, compactness, and low cost.

Molecularly imprinted polymer membranes for a model compound, atrazine, were prepared in situ from a monomer mixture containing methacrylic acid, tri(ethylene glycol) dimethacrylate, and atrazine using UV-initiated polymerization. To improve flexibility and mechanical stability of these membranes, oligourethane acrylate was added to the mixture of monomers. Polymeric additives were used to increase porosity of membranes and their permeability as well as to make them suited for filtration experiments. This process resulted in the formation of thin, flexible, and porous membranes containing atrazine-specific binding sites. The atrazine-imprinted membranes showed higher affinity to this herbicide than to structurally similar compounds (simazine, prometryn, and metribuzin). The binding capacity of MIP membranes was found to be significantly higher than that observed previously for MIP systems. The high affinity, specificity, and binding capacity of MIP membranes, together with their straightforward and easy preparation, provide a good basis for their application in separation and purification, e.g., in membrane chromatography.