The response to pathogens and damage in plants and animals involves a series of carefully orchestrated, highly evolved, molecular mechanisms resulting in pathogen resistance and wound healing. In metazoans, damage- or pathogen-associated molecular pattern molecules (DAMPs, PAMPs) execute precise intracellular tasks and are also able to exert disparate functions when released into the extracellular space. The emergent consequence for both inflammation and wound healing of the abnormal extracellular persistence of these factors may underlie many clinical disorders. DAMPs/PAMPs are recognized by hereditable receptors including the Toll-like receptors, the NOD1-like receptors and retinoic-acid-inducible gene I-like receptors, as well as the receptor for advanced glycation end products. These host molecules 'sense' not only pathogens but also misfolded/glycated proteins or exposed hydrophobic portions of molecules, activating intracellular cascades that lead to an inflammatory response. Equally important are means to not only respond to these molecules but also to eradicate them. We have speculated that their destruction through oxidative mechanisms normally exerted by myeloid cells, such as neutrophils and eosinophils, or their persistence in the setting of pathologic extracellular reducing environments, maintained by exuberant necrotic cell death and/or oxidoreductases, represent important molecular means enabling chronic inflammatory states.

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Facile synthesis and detailed characterization of photopolymerizable and biocompatible poly(ethylene glycol) dimethacrylates (PEGDM) and poly(ethylene glycol) urethane-dimethacrylates (PEGUDM) are described. Poly(ethylene glycol)s of various molecular masses (M(n) = 1000 to 8000 g/mol) were reacted with methacrylic anhydride or with 2-isocyanatoethyl methacrylate to form PEGDMs and PEGUDMs, respectively. PEGDMs were also prepared by a microwave-assisted route to achieve fast reaction conversions under solvent free conditions. Combined analyses of (1)H NMR and MALDI-TOF MS confirmed the formation of prepolymers of high purity and narrow mass distribution (PD < 1.02). Aqueous solutions of the PEGDMs and PEGUDMs (10% and 20% by mass fraction) were photopolymerized to yield hydrogels. Bovine chondrocytes, seeded in the hydrogels, were used to assess the biocompatibility. Preliminary rheology and uniaxial compression measurements showed varied mechanical response, and biocompatibility studies showed that cells are completely viable in both types of hydrogels after two weeks.

In this work, we take previously developed gecko-foot-hair-inspired elastomer microfiber arrays with film-terminated and mushroom-shaped tips that have demonstrated enhanced adhesion with respect to unpatterned materials under dry conditions and coat them with synthetic DOPA-containing mussel-inspired polymers to enhance adhesion repeatedly in fully submerged wet environments. A new protocol for the development of this hybrid patterned, coated adhesive, which is suitable for use in contact with both wet and dry nonflat surfaces, is described. The experimental evaluation of repeatable adhesion under both wet and dry conditions for these materials is described and compared with unpatterned and/or uncoated materials. Macroscale reversible fibrillar adhesion enhancement on a nonflat, smooth glass surface when compared with unpatterned materials under fully submerged conditions is demonstrated with no suction effect.

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An investigation of the ternary phase prism for low molecular weight poly(ethylene oxide), squalane, and poly(ethylene oxide-b-ethylenepropylene) is presented. Comparisons are made between this ternary polymer system and classic water/oil/surfactant mixtures to establish further a universal phase diagram description for amphiphilic systems. A combination of visual isothermal measurements, small-angle X-ray scattering, smallangle neutron scattering, and dynamical mechanical spectrometry was used to characterize phases and determine phase boundaries. A rich phase diagram was revealed, including most of the equilibrium liquid crystalline phases associated with diblock copolymers, regions of two-phase and three-phase coexistence, and a bicontinuous microemulsion. Differences between this polymer phase diagram and those from water/oil/ surfactant systems highlight the strong effect of water in the latter.