Large enhancement in neurite outgrowth on a cell membrane-mimicking conducting polymer.

Although electrically stimulated neurite outgrowth on bioelectronic devices is a promising means of nerve regeneration, immunogenic scar formation can insulate electrodes from targeted cells and tissues, thereby reducing the lifetime of the device. Ideally, an electrode material capable of electrically interfacing with neurons selectively and efficiently would be integrated without being recognized by the immune system and minimize its response. Here we develop a cell membrane-mimicking conducting polymer possessing several attractive features.

3D bioelectronic interface: capturing circulating tumor cells onto conducting polymer-based micro/nanorod arrays with chemical and topographical control.

The three-dimensional (3D) poly(3,4-ethylenedioxythiophene) (PEDOT)-based bioelectronic interfaces (BEIs) with diverse dimensional micro/nanorod array structures, varied surface chemical pro-perties, high electrical conductivity, reversible chemical redox switching, and high optical transparency are used for capturing circulating tumor cells (CTCs). Such 3D PEDOT-based BEIs can function as an efficient clinical diagonstic and therapeutic platform.

Polydioxythiophene nanodots, nonowires, nano-networks, and tubular structures: the effect of functional groups and temperature in template-free electropolymerization.

Various nanostructures, including nanofibers, nanodots, nanonetwork, and nano- to microsize tubes of functionalized poly(3,4-ethylenedioxythiophene) (EDOT) and poly(3,4-propylenedioxythiophene) (ProDOT) are created by using a template-free electropolymerization method on indium-tin-oxide substrates. By investigating conducting polymer nanostructures containing various functional groups prepared at different polymerization temperature, we conclude a synergistic effect of functional groups and temperature on the formation of polymer nanostructures when a template-free electropolymerization method is applied. For unfunctionalized EDOT and ProDOT, or EDOT containing alkyl functional groups, nanofibers and nanoporous structures are usually found.

Oligoethylene-glycol-functionalized polyoxythiophenes for cell engineering: syntheses, characterizations, and cell compatibilities.

A series of methyl- or benzyl-capped oligoethylene glycol functionalized 2,5-dibromo-3-oxythiophenes are synthesized and successfully polymerized by either Grignard metathesis (GRIM) polymerization or reductive coupling polymerization to yield the corresponding polymers in reasonable yields and molecular weights with narrow molecular weight distribution. These synthesized polyoxythiophenes exhibit high electroactivity and stability in aqueous solution when a potential is applied. Polyoxythiophenes from different polymerization approaches display different colors after purification and spectroelectrochemical studies confirm that the difference of color is from the difference of doping state.

Polymer-binding peptides for the noncovalent modification of polymer surfaces: effects of peptide density on the subsequent immobilization of functional proteins.

Peptides that specifically bind to polyetherimide (PEI) were selected, characterized, and used for the noncovalent modification of the PEI surface. The peptides were successfully identified from a phage-displayed peptide library. A chemically-synthesized peptide composed of the Thr-Gly-Ala-Asp-Leu-Asn-Thr sequence showed an extremely high binding constant for the PEI films (5.

Biological selection of peptides for poly(l-lactide) substrates.

Short peptides that recognize the alpha form of poly( l-lactide) (PLLA) crystalline films were identified from a phage-displayed peptide library. An enzyme-linked immunosorbent assay (ELISA) revealed that the apparent binding constants of the phage clones for the alpha form of PLLA were greater than those of the unselected phage library. The specificity index for the alpha form of PLLA referred to a structurally similar atactic poly(methyl methacrylate) (at-PMMA), supporting the alpha form of PLLA specific binding of the selected phage.