title: Poly(3,4-ethylenedioxythiophene):dextran sulfate (PEDOT:DS) - a highly processable conductive organic biopolymer.
abstract: A novel water-dispersible conducting polymer analogous to poly(3,4-dioxythiophene):polystyrene sulfonate (PEDOT:PSS) has been chemically synthesized in a single reaction in high yield. PEDOT:DS, a new member of the polythiophene family, is composed of a complex between PEDOT and the sulfonated polysaccharide polyanion dextran sulfate. Drop-cast films of aqueous suspensions of the material display a native conductivity of up to 7 ± 1 S cm(-1), increasing to 20 ± 2 S cm(-1) after treatment with ethylene glycol and thermal annealing. Mass ratios of the precursors NaDS and EDOT were varied from 5:1 to 2:1 and a decrease in the NaDS:EDOT ratio produces tougher, less hygroscopic films of higher conductivity. Ultraviolet-visible spectroelectrochemistry yields spectra typical of PEDOT complexes. Cyclic voltammetry reveals that PEDOT:DS is electrochemically active from -1.0 to 0.8 V vs. Ag/Ag(+) in acetonitrile, with similar characteristics to PEDOT:PSS. Water dispersions of PEDOT:DS are successfully processed by drop casting, spray coating, inkjet printing and extrusion printing. Furthermore, laser etching of dried films allows the creation of patterns with excellent definition. To assess the cytotoxicity of PEDOT:DS, L-929 cells were cultured with a polymer complex concentration range of 0.002 to 0.2 g l(-1) in cell culture medium. No significant difference is found between the proliferation rates of L-929 cells exposed to PEDOT:DS and those in plain medium after 96h. However, PEDOT:PSS shows around 25% less cell growth after 4 days, even at the lowest concentration. Taken together, these results suggest PEDOT:DS has exceptional potential as an electromaterial for the biointerface.
authors.affiliation: Intelligent Polymer Research Institute, ARC Centre of Excellence for Electromaterials Science, AIIM Facility, University of Wollongong, Wollongong, NSW 2522, Australia.
authors.forename: David G
authors.initials: DG
authors.lastname: Harman
authors.affiliation: Intelligent Polymer Research Institute, ARC Centre of Excellence for Electromaterials Science, AIIM Facility, University of Wollongong, Wollongong, NSW 2522, Australia.
authors.forename: Robert
authors.initials: R
authors.lastname: Gorkin
authors.affiliation: Intelligent Polymer Research Institute, ARC Centre of Excellence for Electromaterials Science, AIIM Facility, University of Wollongong, Wollongong, NSW 2522, Australia.
authors.forename: Leo
authors.initials: L
authors.lastname: Stevens
authors.affiliation: Intelligent Polymer Research Institute, ARC Centre of Excellence for Electromaterials Science, AIIM Facility, University of Wollongong, Wollongong, NSW 2522, Australia.
authors.forename: Brianna
authors.initials: B
authors.lastname: Thompson
authors.affiliation: Intelligent Polymer Research Institute, ARC Centre of Excellence for Electromaterials Science, AIIM Facility, University of Wollongong, Wollongong, NSW 2522, Australia.
authors.forename: Klaudia
authors.initials: K
authors.lastname: Wagner
authors.affiliation: Intelligent Polymer Research Institute, ARC Centre of Excellence for Electromaterials Science, AIIM Facility, University of Wollongong, Wollongong, NSW 2522, Australia.
authors.forename: Bo
authors.initials: B
authors.lastname: Weng
authors.affiliation: Intelligent Polymer Research Institute, ARC Centre of Excellence for Electromaterials Science, AIIM Facility, University of Wollongong, Wollongong, NSW 2522, Australia.
authors.forename: Johnson H Y
authors.initials: JH
authors.lastname: Chung
authors.affiliation: Intelligent Polymer Research Institute, ARC Centre of Excellence for Electromaterials Science, AIIM Facility, University of Wollongong, Wollongong, NSW 2522, Australia; Soft Materials Group, School of Chemistry, University of Wollongong, Wollongong, NSW 2522, Australia.
authors.forename: Marc
authors.initials: M
authors.lastname: In Het Panhuis
authors.affiliation: Intelligent Polymer Research Institute, ARC Centre of Excellence for Electromaterials Science, AIIM Facility, University of Wollongong, Wollongong, NSW 2522, Australia. Electronic address: gwallace@uow.edu.au.
authors.forename: Gordon G
authors.initials: GG
authors.lastname: Wallace
mesh_terms: D000818:Animals; D001704:Biopolymers / Q000494:pharmacology*; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D016264:Dextran Sulfate / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D004553:Electric Conductivity; D055664:Electrochemical Techniques; D051379:Mice; D008855:Microscopy, Electron, Scanning; D009930:Organic Chemicals / Q000494:pharmacology*; D010084:Oxidation-Reduction; D010316:Particle Size; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D013057:Spectrum Analysis; D013696:Temperature
chemical_list: D001704:Biopolymers; D019086:Bridged Bicyclo Compounds, Heterocyclic; D009930:Organic Chemicals; D011108:Polymers; C121383:poly(3,4-ethylene dioxythiophene); D016264:Dextran Sulfate
keywords: Bioelectronics; Dextran sulfate; Electromaterial; Organic electronics; PEDOT