Free-Standing PEDOT:PSS/PLA Bilayer Nanosheets with Ink-Jet Patterned Microelectrodes: Towards the Development of Ultra-
- PDF / 4,766,971 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 87 Downloads / 143 Views
Free-Standing PEDOT:PSS/PLA Bilayer Nanosheets with Ink-Jet Patterned Microelectrodes: Towards the Development of Ultra-Thin, Conformable, Floating Circuits and Smart Biointerfaces. Alessandra Zucca1,2, Francesco Greco1*, Barbara Mazzolai1 and Virgilio Mattoli1 1 Center for MicroBioRobotics @SSSA, Istituto Italiano di Tecnologia, Viale Rinaldo Piaggio 34, 56025 Pontedera (Italy). 2 Biorobotics Institute, Scuola Superiore Sant’Anna, Polo Sant’Anna Valdera, Viale Rinaldo Piaggio 34, 56025 Pontedera (Italy). ABSTRACT Novel solutions and applications in the biomedical field could come from exploiting the electroactive properties of conducting polymers towards the development of responsive smart biointerfaces and of flexible, conformable, biocompatible systems. In this sense it is mandatory to control material’s conductivity in situ and this requires the development of suitable patterning processes and the fabrication of individually addressable microelectrodes. Based on the recent introduction by our group of free-standing nanofilms of conductive polymers, the aim of this work was to describe a method for the fabrication of patterned ultra-thin free-standing PEDOT:PSS/Poly (lactic acid) (PLA) bilayer nanosheets. The proposed method involves an inkjet patterning technique, based on localized overoxidation of PEDOT:PSS by means of a sodium hypochlorite solution. Here we described the fabrication method and characterized the realized nanosheets in terms of their thickness, contact angle, conductivity. The overall process permitted to realize patterned free-standing nanosheets that, despite their low thickness, are very robust and conformable on tissues or on soft and rigid substrates, while allowing for an electrical control of their surface properties. Possible applications are foreseen in the field of conformable electronics, e.g. as electrodes on the brain or smart conductive substrates for cell culturing and stimulation. INTRODUCTION Recently we demonstrated the fabrication of robust and flexible all-polymer free-standing conductive nanofilms having very large surface area with typical nano-scale thickness (40-120 nm) by employing thin-film assembly and release techniques.[1-2] Nanofilms are made with poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS), a conductive polymer that has been used in many different biomedical applications among others [3]. In such applications there is a growing interest in exploiting the dynamic eletroactive properties of conjugated polymers (e.g. the reversible electrochemical switching of surface properties and the electromechanical actuation)[4-7] that could open the way to the development of dynamic patterns and to the tunable control of surface conductivity in situ. Patterning of surface conductivity of free-standing nanofilms is also particularly interesting for the development of free-standing ultrathin logic circuits and of conformable electronic devices. In recent years the field of conformable electronics has attracted a considerable interest for the realization
Data Loading...
