title: Electric field stimulation through a biodegradable polypyrrole-co-polycaprolactone substrate enhances neural cell growth.
abstract: Nerve guidance conduits (NGCs) are FDA-approved devices used to bridge gaps across severed nerve cables and help direct axons sprouting from the proximal end toward the distal stump. In this article, we present the development of a novel electrically conductive, biodegradable NGC made from a polypyrrole-block-polycaprolactone (PPy-PCL) copolymer material laminated with poly(lactic-co-glycolic acid) (PLGA). The PPy-PCL has a bulk conductivity ranging 10-20 S/cm and loses 40 wt % after 7 months under physiologic conditions. Dorsal root ganglia (DRG) grown on flat PPy-PCL/PLGA material exposed to direct current electric fields (EF) of 100 mV/cm for 2 h increased axon growth by 13% (± 2%) toward either electrode of a 2-electrode setup, compared with control grown on identical substrates without EF exposure. Alternating current increased axon growth by 21% (±3%) without an observable directional preference, compared with the same control group. The results from this study demonstrate PLGA-coated PPy-PCL is a unique biodegradable material that can deliver substrate EF stimulation to improve axon growth for peripheral nerve repair.
authors: Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas, 78712.
authors: Hieu T
authors: HT
authors: Nguyen
authors: Shawn
authors: S
authors: Sapp
authors: Claudia
authors: C
authors: Wei
authors: Jacqueline K
authors: JK
authors: Chow
authors: Alvin
authors: A
authors: Nguyen
authors: Jeff
authors: J
authors: Coursen
authors: Silvia
authors: S
authors: Luebben
authors: Emily
authors: E
authors: Chang
authors: Robert
authors: R
authors: Ross
authors: Christine E
authors: CE
authors: Schmidt
mesh_terms: D000818:Animals; D001369:Axons / Q000187:drug effects / Q000378:metabolism; D001672:Biocompatible Materials / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D002208:Caproates / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D002448:Cell Adhesion / Q000187:drug effects; D002452:Cell Count; D016923:Cell Death / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004553:Electric Conductivity; D004558:Electric Stimulation; D005727:Ganglia, Spinal / Q000166:cytology / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D007783:Lactones / Q000138:chemical synthesis / Q000737:chemistry / Q000493:pharmacokinetics*; D008970:Molecular Weight; D009474:Neurons / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D016716:PC12 Cells; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry / Q000493:pharmacokinetics* / Q000494:pharmacology*; D011758:Pyrroles / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D001672:Biocompatible Materials; D002208:Caproates; D007783:Lactones; D011108:Polymers; D011758:Pyrroles; C000594957:polypyrrole-co-polycaprolactone; C067635:polypyrrole
keywords: cell stimulation; degradable polypyrrole; electric field; nerve conduit; nerve regeneration
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