Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

The roles of an aluminum underlayer in the biocompatibility and mechanical integrity of vertically aligned carbon nanotubes for interfacing with retinal neurons

Watterson, William J. ; Moslehi, Saba ; Rowland, Conor ; Zappitelli, Kara M. ; Smith, Julian H. ; Miller, David ; Chouinard, Julie E. ; Golledge, Stephen L. ; Taylor, Richard P. and Perez, Maria Thereza LU , et al. (2020) In Micromachines 11(6).
Abstract

Retinal implant devices are becoming an increasingly realizable way to improve the vision of patients blinded by photoreceptor degeneration. As an electrode material that can improve restored visual acuity, carbon nanotubes (CNTs) excel due to their nanoscale topography, flexibility, surface chemistry, and double-layer capacitance. If vertically aligned carbon nanotubes (VACNTs) are biocompatible with retinal neurons and mechanically robust, they can further improve visual acuity-most notably in subretinal implants-because they can be patterned into high-aspect-ratio, micrometer-size electrodes. We investigated the role of an aluminum (Al) underlayer beneath an iron (Fe) catalyst layer used in the growth of VACNTs by chemical vapor... (More)

Retinal implant devices are becoming an increasingly realizable way to improve the vision of patients blinded by photoreceptor degeneration. As an electrode material that can improve restored visual acuity, carbon nanotubes (CNTs) excel due to their nanoscale topography, flexibility, surface chemistry, and double-layer capacitance. If vertically aligned carbon nanotubes (VACNTs) are biocompatible with retinal neurons and mechanically robust, they can further improve visual acuity-most notably in subretinal implants-because they can be patterned into high-aspect-ratio, micrometer-size electrodes. We investigated the role of an aluminum (Al) underlayer beneath an iron (Fe) catalyst layer used in the growth of VACNTs by chemical vapor deposition (CVD). In particular, we cultured dissociated retinal cells for three days in vitro (DIV) on unfunctionalized and oxygen plasma functionalized VACNTs grown from a Fe catalyst (Fe and Fe + Pl preparations, where Pl signifies the plasma functionalization) and an Fe catalyst with an Al underlayer (Al/Fe and Al/Fe + Pl preparations). The addition of the Al layer increased the mechanical integrity of the VACNT interface and enhanced retinal neurite outgrowth over the Fe preparation. Unexpectedly, the extent of neurite outgrowth was significantly greater in the Al/Fe than in the Al/Fe+Pl preparation, suggesting plasma functionalization can negatively impact biocompatibility for some VACNT preparations. Additionally, we show our VACNT growth process for the Al/Fe preparation can support neurite outgrowth for up to 7 DIV. By demonstrating the retinal neuron biocompatibility, mechanical integrity, and pattern control of our VACNTs, this work offers VACNT electrodes as a solution for improving the restored visual acuity provided by modern retinal implants.

(Less)
Please use this url to cite or link to this publication:
author
; ; ; ; ; ; ; ; and , et al. (More)
; ; ; ; ; ; ; ; ; and (Less)
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Biomaterials, Cell culture, Glia, Retinal implants, Retinal neurons, VACNTs
in
Micromachines
volume
11
issue
6
article number
546
publisher
MDPI AG
external identifiers
  • scopus:85087052419
ISSN
2072-666X
DOI
10.3390/MI11060546
language
English
LU publication?
yes
id
65e4b9ed-02a0-43c1-8812-359739ccdc2b
date added to LUP
2020-07-08 11:54:45
date last changed
2023-11-20 07:48:09
@article{65e4b9ed-02a0-43c1-8812-359739ccdc2b,
  abstract     = {{<p>Retinal implant devices are becoming an increasingly realizable way to improve the vision of patients blinded by photoreceptor degeneration. As an electrode material that can improve restored visual acuity, carbon nanotubes (CNTs) excel due to their nanoscale topography, flexibility, surface chemistry, and double-layer capacitance. If vertically aligned carbon nanotubes (VACNTs) are biocompatible with retinal neurons and mechanically robust, they can further improve visual acuity-most notably in subretinal implants-because they can be patterned into high-aspect-ratio, micrometer-size electrodes. We investigated the role of an aluminum (Al) underlayer beneath an iron (Fe) catalyst layer used in the growth of VACNTs by chemical vapor deposition (CVD). In particular, we cultured dissociated retinal cells for three days in vitro (DIV) on unfunctionalized and oxygen plasma functionalized VACNTs grown from a Fe catalyst (Fe and Fe + Pl preparations, where Pl signifies the plasma functionalization) and an Fe catalyst with an Al underlayer (Al/Fe and Al/Fe + Pl preparations). The addition of the Al layer increased the mechanical integrity of the VACNT interface and enhanced retinal neurite outgrowth over the Fe preparation. Unexpectedly, the extent of neurite outgrowth was significantly greater in the Al/Fe than in the Al/Fe+Pl preparation, suggesting plasma functionalization can negatively impact biocompatibility for some VACNT preparations. Additionally, we show our VACNT growth process for the Al/Fe preparation can support neurite outgrowth for up to 7 DIV. By demonstrating the retinal neuron biocompatibility, mechanical integrity, and pattern control of our VACNTs, this work offers VACNT electrodes as a solution for improving the restored visual acuity provided by modern retinal implants.</p>}},
  author       = {{Watterson, William J. and Moslehi, Saba and Rowland, Conor and Zappitelli, Kara M. and Smith, Julian H. and Miller, David and Chouinard, Julie E. and Golledge, Stephen L. and Taylor, Richard P. and Perez, Maria Thereza and Alemán, Benjamín J.}},
  issn         = {{2072-666X}},
  keywords     = {{Biomaterials; Cell culture; Glia; Retinal implants; Retinal neurons; VACNTs}},
  language     = {{eng}},
  number       = {{6}},
  publisher    = {{MDPI AG}},
  series       = {{Micromachines}},
  title        = {{The roles of an aluminum underlayer in the biocompatibility and mechanical integrity of vertically aligned carbon nanotubes for interfacing with retinal neurons}},
  url          = {{http://dx.doi.org/10.3390/MI11060546}},
  doi          = {{10.3390/MI11060546}},
  volume       = {{11}},
  year         = {{2020}},
}