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The formation of polymer supramolecular networks exhibiting selective sensitivity toward a narrow class of organic compounds is still a significant challenge within the area of reversibly cross-linked materials. Glycoluril molecular clips are U-shaped molecules, which, besides the ability to undergo self-sorting homodimerization, exhibit selectively high molecular recognition of dihydroxyaromatic species. A glycoluril clip diol was introduced into a polymer backbone by using standard polyurethane chemistry. Immobilization of the molecular clip along the polyurethane macromolecule (Glyc Clip-polyurethane) was shown to preserve the native association properties of the clip. Clip motifs embedded in macromolecules form homodimer cross-links in CHCl3 and the resulting structures have a thermoresponsive character. The strength of homodimerization Khomodimer varies from 7.74 104 l mol-1 at 265 K to 9.47 102 l mol-1 at 315 K. A 30 wt % solution of Glyc Clip-polyurethane undergoes gelation at room temperature and exhibits a constant elastic modulus, approximately 3.1 ⋅ 104 Pa, in the broad investigated frequency range. The obtained organogels exhibit selective chemoresponsive properties in the presence of resorcinol, which was demonstrated with 1 H high-resolution magic-angle-spinning NMR spectroscopy and rheological measurements.

This paper describes various methods of preparation and characterization of supports (e.g. silicon, polymer, and metal) with grafted polymers and copolymers, which were tailored for biomedical applications. In particular, there are described methods related to preparation of substrates by surface modification leading to incorporation of initiators and, eventually, various polymerization methods yielding complete, dense, and efficient polymer or copolymer coverage with desired arrangement of polymers/copolymers chains, sufficient chains density, and thickness of a polymer layer. Special attention is drawn to the description of manufacturing of patterned polymer stimuli responsive brushes that are sensitive to changes, for example, temperature, pH, hydrophilicity, solvent, and ionic strength. Selected applications of supports containing tethered polymer brushes used as modern materials useful in biosciences, particularly as elements of biosensors, materials for diagnostics, and prostheses, as well as in other areas of micro-technology and nanotechnology are discussed. Copyright © 2015 John Wiley & Sons, Ltd.

Interactions of human serum albumin, gamma globulins and alkaline phosphatase with surface of hydrophilic microspheres are described. Relation between the composition of particles surface layer and adsorption/covalent immobilization and activity of proteins is elucidated. The set of poly(styrene/α-tert-butoxy-ω-vinylbenzyl-polyglycidol) microspheres (poly(S/PGly)) was synthesized via emulsion copolymerization of styrene and α-tert-butoxy-ω-vinylbenzyl-polyglycidol (PGL) macromonomer (Mn = 3000, Mw/Mn = 1.08). The way of addition of PGL macromonomer was different in particular subsets of syntheses; however, the total concentration of all compounds added to the polymerization mixture was kept constant. Namely, PGL was continuously injected beginning injection at various stages of styrene conversion or it was added together with styrene at the beginning of the polymerization. The syntheses yielded microspheres with a number average diameter measured by SEM in a range from 300 to 564.7 nm, and dispersities (Dw/Dn) lower than 1.004, depending on the method of addition of PGL to the polymerization mixture. Studies of proteins' adsorption allowed for determination of relation between the surface concentration of adsorbed protein and chemical composition of the particles interfacial layer. Activation of hydroxyl groups in polyglycidol by 1,3,5-trichlorotriazine allowed for the controlled covalent immobilization of proteins onto particles. The accompanying physical adsorption was low. Studies of the activity of alkaline phosphatase covalently bonded to the surface of the poly(S/PGly) particles with the fraction of PGL in the particles' interfacial layer (fPGL = 20.6 mol% revealed that the activity of the covalently immobilized enzyme was 4.6 times higher than activity of the enzyme adsorbed on the surface of the polystyrene microspheres. Copyright © 2014 John Wiley & Sons, Ltd.