title: Boron-Doped Nanocrystalline Diamond Electrodes for Neural Interfaces: In vivo Biocompatibility Evaluation.
abstract: Boron-doped nanocrystalline diamond (BDD) electrodes have recently attracted attention as materials for neural electrodes due to their superior physical and electrochemical properties, however their biocompatibility remains largely unexplored. In this work, we aim to investigate the in vivo biocompatibility of BDD electrodes in relation to conventional titanium nitride (TiN) electrodes using a rat subcutaneous implantation model. High quality BDD films were synthesized on electrodes intended for use as an implantable neurostimulation device. After implantation for 2 and 4 weeks, tissue sections adjacent to the electrodes were obtained for histological analysis. Both types of implants were contained in a thin fibrous encapsulation layer, the thickness of which decreased with time. Although the level of neovascularization around the implants was similar, BDD electrodes elicited significantly thinner fibrous capsules and a milder inflammatory reaction at both time points. These results suggest that BDD films may constitute an appropriate material to support stable performance of implantable neural electrodes over time.
authors.affiliation: Laboratory for Stem Cell Research, Department of Health Science and Technology, Aalborg University Aalborg, Denmark.
authors.forename: María
authors.initials: M
authors.lastname: Alcaide
authors.affiliation: Institute of Physics, Academy of Sciences of the Czech Republic v.v.iPrague, Czech Republic; Nano6 s.r.o.Kladno, Czech Republic.
authors.forename: Andrew
authors.initials: A
authors.lastname: Taylor
authors.affiliation: Neurodan A/S Aalborg, Denmark.
authors.forename: Morten
authors.initials: M
authors.lastname: Fjorback
authors.affiliation: Laboratory for Stem Cell Research, Department of Health Science and Technology, Aalborg University Aalborg, Denmark.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Zachar
authors.affiliation: Laboratory for Stem Cell Research, Department of Health Science and Technology, Aalborg University Aalborg, Denmark.
authors.forename: Cristian P
authors.initials: CP
authors.lastname: Pennisi
keywords: biocompatible materials; boron-doped diamond; foreign body reaction; in vivo models; nanocrystalline diamond; neural electrodes; neuroprosthetic interfaces; titanium nitride