Microfibrous PEDOT scaffold for neural recordings

Abstract

Event Abstract Back to Event Microfibrous PEDOT scaffold for neural recordings Jason Marroquin1, Kun Zhou1, Bjorn Winther-Jensen1, Harry Coleman2, Helena Parkington2 and John S. Forsythe1 1 Monash University, Materials Engineering, Australia 2 Monash University, Physiology, Australia Current neural interfaces used for both recording and stimulating neurons have great potential in neurophysiological research to help understand processes, and in biomedical applications to restore some functions in the nervous system, e.g. prostheses, bionic implants. However, there presently exist serious limitations in obtaining stable, consistent and long-term stimulation or recording, mainly due to an unwanted glial response. The scar increases resistance to current flow as well as the distance between the neurons and the current source [1]. Consequently, higher electrical currents or voltages are required, which result in damage to neural tissue due to Faradaic reactions. Additionally, most neural interfaces have limited proximity to neurons (due to their 2D recording sites), which is greatly compromised once a glial response occurs [2]. In the present study, a microfibrous 3D neural electrode is under development using a PLLA electrospun template. The fibrous template was imbued with electroactive properties by coating with PEDOT, a conductive polymer, via vapour phase polymerization. The electrical properties of the PEDOT-coated substrates were studied in terms of sheet resistance measured by a 4-point probe, and scaffold morphology was investigated by scanning electron microscopy. Scaffold biocompatibility was assessed through in vitro assay of rat primary hippocampal neurons using patch clamp electrophysiology, calcium imaging (using fluorescent indicator Fluo-4) and immunocytochemistry. Importantly, the in vitro assays demonstrated normal spontaneous neural activity, indicating robust neural networking, up to 40 days in culture on PEDOT scaffolds.