Synthesis, copolymerization and peptide-modification of carboxylic acid-functionalized 3,4-ethylenedioxythiophene (EDOTacid) for neural electrode interfaces

• Published in: Biochimica et biophysica acta Vol. 1830; no. 9; pp. 4288 - 4293
• Main Authors: Povlich, Laura K., Cho, Jae Cheol, Leach, Michelle K., Corey, Joseph M., Kim, Jinsang, Martin, David C.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.09.2013
• Subjects: Adhesion; Animals; bioactive properties; Biocompatible Materials - chemical synthesis; Biocompatible Materials - chemistry; Biomaterial; Bridged Bicyclo Compounds, Heterocyclic - chemical synthesis; Bridged Bicyclo Compounds, Heterocyclic - chemistry; Carboxylic Acids - chemical synthesis; Carboxylic Acids - chemistry; Cells, Cultured; composite polymers; Conjugated polymer; Electrochemical; electrodes; Electrodes, Implanted; medicine; motor neurons; Motor Neurons - physiology; Neuron; peptides; Peptides - chemistry; Polymerization; Polymers - chemical synthesis; Polymers - chemistry; prostheses; Rats; RGD; Conjugated polymer; Biomaterial; Neuron; Adhesion; RGD; Electrochemical
• ISSN: 0304-4165; 0006-3002; 1872-8006
• DOI: 10.1016/j.bbagen.2012.10.017

Conjugated polymers have been developed as effective materials for interfacing prosthetic device electrodes with neural tissue. Recent focus has been on the development of conjugated polymers that contain biological components in order to improve the tissue response upon implantation of these electrodes. Carboxylic acid-functionalized 3,4-ethylenedioxythiophene (EDOTacid) monomer was synthesized in order to covalently bind peptides to the surface of conjugated polymer films. EDOTacid was copolymerized with EDOT monomer to form stable, electrically conductive copolymer films referred to as PEDOT-PEDOTacid. The peptide GGGGRGDS was bound to PEDOT-PEDOTacid to create peptide functionalized PEDOT films. The PEDOT-PEDOTacid-peptide films increased the adhesion of primary rat motor neurons between 3 and 9 times higher than controls, thus demonstrating that the peptide maintained its biological activity. The EDOT-acid monomer can be used to create functionalized PEDOT-PEDOTacid copolymer films that can have controlled bioactivity. PEDOT-PEDOTacid-peptide films have the potential to control the behavior of neurons and vastly improve the performance of implanted electrodes. This article is part of a Special Issue entitled Organic Bioelectronics—Novel Applications in Biomedicine. [Display omitted] ► We describe the synthesis and characterization of an acid-functionalized EDOT monomer. ► The EDOTacid monomer is combined with EDOT to create a P(EDOT-EDOTacid) copolymer. ► The copolymer is functionalized by RGD peptide, and dramatically improves neural cell adhesion.