Luisa Vanessa Steingrube (Hannover, DE), Jörn Baumgarten (Hannover, DE), Dr. Madeleine Goblet (Hannover, DE), Dr. Jennifer Harre (Hannover, DE), Timo Herrmann (Hannover, DE), Dr. Nina Ehlert (Hannover, DE), Professor Athanasia Warnecke (Hannover, DE), Professor Thomas Lenarz (Hannover, DE), Prof. Dr. Peter Behrens (Hannover, DE)
Abstract text (incl. figure legends and references)
Introduction
The effects of hearing loss are restricting for the sufferers. Inserting a cochlear implant, which stimulates the remaining spiral ganglion neurons (SGNs), is the most common treatment for hearing loss caused by hair cell loss. The relatively large gap between the cochlear electrode and these neurons is a crucial problem. Quality of signal transmission is lost as a consequence. An improvement in electrode-nerve contact is required for a better auditory experience.
Objectives
To reduce the distance between the electrode and the SGNs a composite material is synthesised. Brain-derived neurotrophic factor (BDNF) and neurotrophic factor 3 (NT-3)-containing nanoporous silica nanoparticles (NPSNPs) will be attached to the silicone surface. To overcome the silicone"s inertness, a polymer coating should be created first.
Materials & methods
Different silanes were used to modify the synthesised NPSNPs.
For immobilisation in a growth factor solution combining BDNF and NT-3, amino-modified particles were utilised.
An UV-initiated radical reaction in an aqueous acrylate solution was used to create the polymer coating. As a radical initiator, benzophenone was used. Particles that have been allyl-modified were added to the monomer solution for particle integration into the coating.
Results
The particles were successfully modified which can be drawn from nitrogen physisorption, zeta potential and thermogravimetric measurements.
Release experiments proved that BDNF and NT-3 were immobilised reversibly at the particles.
Moreover, the successful polymer coating was confirmed by FTIR, XPS and water contact angle measurements. The particle integration was determined by SEM investigation.
Conclusion
As a result, it has been proven that NPSNPs can release BDNF and NT-3. Additionally, the polymer coating can be used to adhere NPSNPs to the silicone surface. These two findings will be combined to create a potential composite material for a local cochlea drug delivery system.