title: Well-ordered porous conductive polypyrrole as a new platform for neural interfaces.
abstract: We present the preparation of electrically conductive, porous polypyrrole surfaces and demonstrate their use as an interactive substrate for neuronal growth. Nerve growth factor (NGF)-loaded porous conducting polymers were initially prepared by electrochemical deposition of a mixture of pyrrole monomers and NGF into two- or three-dimensional particle arrays followed by subsequent removal of a sacrificial template. Morphological observation by scanning electron microscopy (SEM) revealed these to possess high regularity and porosity with well-defined topographical features. A four-point probe study demonstrated remarkable electrical activities despite the presence of voids. In addition, we investigated the effects of these surfaces on cellular behaviors using PC 12 cells in the presence and absence of electrical stimulation. Our results suggest that the surface topography as well as an applied electrical field can play a crucial role in determining further cell responses. Indeed, surface-induced preferential regulation leads to enhanced cellular viability and neurite extension. Establishing the underlying cellular mechanisms in response to various external stimuli is essential in that one can elicit positive neuronal guidance and modulate their activities by engineering a series of electrical, chemical, and topographical cues.
authors.affiliation: Center for Paralysis Research, Department of Basic Medical Sciences, School of Veterinary Medicine, Purdue University, West Lafayette, Indiana 47907, United States.
authors.forename: Grace
authors.initials: G
authors.lastname: Kang
authors.forename: Richard Ben
authors.initials: RB
authors.lastname: Borgens
authors.forename: Youngnam
authors.initials: Y
authors.lastname: Cho
mesh_terms: D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D004553:Electric Conductivity; D004558:Electric Stimulation; D020932:Nerve Growth Factor / Q000378:metabolism; D009474:Neurons / Q000166:cytology* / Q000187:drug effects* / Q000378:metabolism; D016716:PC12 Cells; D011108:Polymers / Q000737:chemistry* / Q000494:pharmacology*; D016062:Porosity; D011758:Pyrroles / Q000737:chemistry* / Q000494:pharmacology*; D051381:Rats; D013499:Surface Properties
chemical_list: D011108:Polymers; D011758:Pyrroles; C067635:polypyrrole; D020932:Nerve Growth Factor