The effect of polypyrrole with incorporated neurotrophin-3 on the promotion of neurite outgrowth from auditory neurons

Abstract This research aims to improve the nerve–electrode interface of the cochlear implant using polymer technology to encourage neuron survival, elongation and adhesion to the electrodes. Polypyrrole (Ppy) doped with p -toluene sulphonate (pTS) is an electroactive polymer into which neurotrophin-...

Full description

Saved in:
Bibliographic Details
Published in:Biomaterials 2007-01, Vol.28 (3), p.513-523
Main Authors: Richardson, Rachael T, Thompson, Brianna, Moulton, Simon, Newbold, Carrie, Lum, May Ghee, Cameron, Adrian, Wallace, Gordon, Kapsa, Robert, Clark, Graeme, O’Leary, Stephen
Format: Article
Language:English
Subjects:
Advanced Basic Science
Animals
Benzenesulfonates - chemistry
Biocompatible Materials - chemistry
Controlled drug release
Dentistry
Electric Impedance
Electrical stimulation
Electroactive polymer
Electrodes
Female
Male
Nerve growth factor
Nerve Regeneration
Neurites - metabolism
Neurons - metabolism
Neurons, Afferent - metabolism
Neurotrophin 3 - chemistry
Polymers - chemistry
Pyrroles - chemistry
Rats
Rats, Wistar
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Abstract This research aims to improve the nerve–electrode interface of the cochlear implant using polymer technology to encourage neuron survival, elongation and adhesion to the electrodes. Polypyrrole (Ppy) doped with p -toluene sulphonate (pTS) is an electroactive polymer into which neurotrophin-3 (NT3) can be incorporated. Ppy/pTS±NT3 was synthesised over gold electrodes and used as a surface for auditory neuron explant culture. Neurite outgrowth from explants grown on Ppy/pTS was equivalent to tissue culture plastic but improved with the incorporation of NT3 (Ppy/pTS/NT3). Electrical stimulation of Ppy/pTS/NT3 with a biphasic current pulse, as used in cochlear implants, significantly improved neurite outgrowth from explants. Using125 I-NT3, it was shown that low levels of NT3 passively diffused from Ppy/pTS/NT3 during normal incubation and that electrical stimulation enhanced the release of biologically active NT3 in quantities adequate for neuron survival. Furthermore, Ppy/pTS/NT3 and its constituents were not toxic to auditory neurons and the Ppy/pTS/NT3 coating on gold electrodes did not alter impedance. If applied to the cochlear implant, Ppy/pTS/NT3 will provide a biocompatible, low-impedance substrate for storage and release of NT3 to help protect auditory neurons from degradation after sensorineural hearing loss and encourage neurite outgrowth towards the electrodes.
ISSN:0142-9612
1878-5905
DOI:10.1016/j.biomaterials.2006.09.008