Novel highly stable conductive polymer composite PEDOT:DBSA for bioelectronic applications

Abstract

In this work, a novel conductive polymer composite consisting of poly(3,4-ethylenedioxythiophene) doped with dodecylbenzenesulfonic acid (PEDOT:DBSA) for bioelectronic applications was prepared and optimized. The novel PEDOT:DBSA composite possesses superior biocompatibility toward cell culture and electrical characteristics comparable to the widely used PEDOT:PSS. The cross-linking processes induced by the cross-linker glycidoxypropyltrimethoxysilane (GOPS), which was investigated in detail using Fourier transform Raman spectroscopy and XPS analysis, lead to the excellent long-term stability of PEDOT:DBSA thin films in aqueous solutions, even without treatment at high temperature. The electrical characteristics of PEDOT:DBSA thin films with respect to the level of cross-linking were studied in detail. The conductivity of thin films was significantly improved using sulfuric acid posttreatment. A model transistor device based on PEDOT:DBSA shows typical transistor behavior and suitable electrical properties comparable or superior to those of available conductive polymers in bioelectronics, such as PEDOT:PSS. Based on these properties, the newly developed material is well suited for bioelectronic applications that require long-term contact with living organisms, such as wearable or implantable bioelectronics.