Application and characterization of neural probes

• Grant number: 16/18314-0
• Support type: Scholarships in Brazil - Post-Doctorate
• Effective date (Start): October 01, 2016
• Effective date (End): September 30, 2020
• Field of knowledge: Health Sciences - Medicine
• Principal Investigator: Fernando Cendes
• Grantee: Elayne Vieira Dias
• Home Institution: Faculdade de Ciências Médicas (FCM). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 13/07559-3 - BRAINN - The Brazilian Institute of Neuroscience and Neurotechnology, AP.CEPID

Abstract

This study will record single unit activity using neural probes designed and fabricated in associated BRAINN research projects. For this objective, probes will be chronically implanted in either normal or epilepsy model rats using stereotaxic surgery. Recordings will be performed using a multichannel recording and digitalizing equipment (Intan Tecnologies USA) in freely moving, behaving rats, either during electrical stimulation for the induction of seizures and during spontaneous behaviors with no electrical stimulation.The nervous tissue of rats that received chronical probe implants will be analyzed with immunofluorescence labeling for markers for foreign body reaction such as the astrogliosis markers GFAP and microglia activation marker CD68. Gene expression analysis of tissue reactivity markers will also be performed in laser microdissected regions proximal to probe implantation and will be subjected to transcriptome analysis by RNA-seq.Finally, the present study will investigate the use of various schemes for the improvement of long-term probe stability, based on surface modifications and coatings. It will also investigate the optimization of electrodes both for electrical recording and for stimulation. Materials work will focus on the use of commercially available formulations such as hydrogels. Probe coatings will include commercially available polymers such as HEMA, HPMA, and PGSA; porous and texturized surfaces including dendrites, nano-filaments and fibers; hydrophobic treatments (for instance the use of silanization methods); and naturally occurring materials such as hyaluronic acid. Finally, this task will investigate various electrode materials and their processing, in particular platinum (platinum black, platinum grey, platinum brown), iridium oxide, ruthenium and other platinum group metals, and PEDOT, for the improved performance of microelectrodes both under electrical recording and under stimulation. (AU)