Functional thin film polymers for biopassivation of neuroprosthetic implants

Neuroprosthetics is the investigation of methods to control external electronic devices utilizing recorded neuronal firing patterns. These investigations are crucial to the quality of life of quadriplegic patients. Central to this field is the ability to implant neural recording probes within the brain that will remain functional over the life of the patient. In this work, two novel polymeric materials for use in biopassive neural probe coatings have been developed and validated. These polymers are synthesized by initiated chemical vapor deposition to allow conformal, pin-hole free coatings of high aspect ratio neural probe assemblies. The first developed material is an electrically insulating barrier coating for the protection of neural probe assemblies. The polymer, poly(trivinyltrimethylcyclotrisiloxane), has an electrical resistivity of 4 X 1015 Ohm-cm and has been demonstrated to be smooth (RMS roughness < 0.4 nm), adherent to silicon substrates, insoluble, and hydrolytically stable. Long term soak testing under physiological conditions has demonstrated retention of electrical properties for > 1000 days. In addition, initial cytotoxicity testing indicates that the material is biocompatible with PC 12 neurons. The second developed material, poly(pentfluorophenyl methacrylate-co-ethylene glycol diacrylate), was developed as a platform for easy surface functionalization of neural probe coatings with bioactive molecules.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Chemical Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2007

Author dc:creator

• O'Shaughnessy, Wm. Shannan

Advisor dc:contributor.advisor

• Karen K. Gleason.

• Chemical Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/38965
• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Identifier URI

http://dspace.mit.edu/handle/1721.1/38965

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/38965