. . . . . . . . . .    ANM 2010     3rd International Conference on Advanced Nano Materials     12-15 September 2010 - Agadir, Morocco Back    Abstract ANMM261 MUSSEL-INSPIRED CHEMISTRY OF CATECHOL AND CATECHOLAMINE FOR BIOINTERFACE RESEARCH Haeshin Lee Department of Chemistry Department of Nanoscience and Technology KAIST (Korea Adv. Institute of Sci. Tech.) . The use of catechol and catecholamine that are found in a variety of marine living creatures becomes a rapidly emerging field in biointerface research. In particular, adhesive and cohesive properties of pads and threads of mussels are the results from precisely controlled chemistry of catechol and catecholamine. Herein, we present three examples of chemistry of catecholamine: nanoparticle synthesis, cell adhesion and hydrogel formation. First, we developed a method for the on-surface synthesis of metallic nanoparticles on versatile substrates. Unlike existing surface modification techniques such as self-assembled monolayer and organosilane functionalization, the polymerized dopamine effectively functions as an adhesive-reducing agent (ARA) that supplies electrons for the on-surface growth of metallic nanoparticles. As it offers a virtually unlimited selection of materials and experimental simplicity, the ARA-mediated on-surface synthesis approach is an extremely useful toolkit for a variety of fields, including catalysts, plasmonics, and sensors. Second, modifications of surfaces by polymerized dopamine, facilitate cell adhesion on well-known anti-adhesive, non-wetting substrates, poly(tetrafluoroethylene) and many other hydrophobic substrates. Surface analysis demonstrated that the polydopamine retained native structures of adhered serum proteins. Thus, the adhered cells underwent general cell adhesion processes of substrate attachment, spreading, and cytoskeleton development. Third, we developed a new biomimetic approach for PEG hydrogel formations. Catechol, as a crosslinking moiety, was end-functionalized to multi-arm PEGs. We used a slight chemical variation in linking chemistry between catechol end groups and PEGs (amide and secondary amine formation) and this resulted in significant differences in the kinetics of gelation and mechanical properties of the hydrogels. In contrast to the large amount of the previous study in which researchers have focused on stimulus-sensitivity, choice of polymeric backbones, and control of gelation kinetics and mechanical properties in hydrogels, this study showed that the simple design of an overlooked factor, a linker, has considerable influences in overall aspects of gelation such as kinetics and mechanical properties. . © nanoAC . . . . . . . . . .

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