Biocompatibility of biodegradable semiconducting melanin films for nerve tissue engineering

Biomaterials. 2009 Jun;30(17):3050-7. doi: 10.1016/j.biomaterials.2009.02.018. Epub 2009 Mar 14.

Abstract

The advancement of tissue engineering is contingent upon the development and implementation of advanced biomaterials. Conductive polymers have demonstrated potential for use as a medium for electrical stimulation, which has shown to be beneficial in many regenerative medicine strategies including neural and cardiac tissue engineering. Melanins are naturally occurring pigments that have previously been shown to exhibit unique electrical properties. This study evaluates the potential use of melanin films as a semiconducting material for tissue engineering applications. Melanin thin films were produced by solution processing and the physical properties were characterized. Films were molecularly smooth with a roughness (R(ms)) of 0.341 nm and a conductivity of 7.00+/-1.10 x 10(-5)S cm(-1) in the hydrated state. In vitro biocompatibility was evaluated by Schwann cell attachment and growth as well as neurite extension in PC12 cells. In vivo histology was evaluated by examining the biomaterial-tissue response of melanin implants placed in close proximity to peripheral nerve tissue. Melanin thin films enhanced Schwann cell growth and neurite extension compared to collagen films in vitro. Melanin films induced an inflammation response that was comparable to silicone implants in vivo. Furthermore, melanin implants were significantly resorbed after 8 weeks. These results suggest that solution-processed melanin thin films have the potential for use as a biodegradable semiconducting biomaterial for use in tissue engineering applications.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Newborn
  • Biocompatible Materials / chemistry*
  • Biodegradation, Environmental
  • Cell Adhesion
  • Cell Culture Techniques
  • Cells, Cultured
  • Electric Conductivity*
  • Implants, Experimental
  • Materials Testing / methods
  • Melanins / chemistry*
  • Nerve Regeneration / physiology*
  • PC12 Cells
  • Rats
  • Rats, Sprague-Dawley
  • Schwann Cells / cytology
  • Schwann Cells / physiology
  • Spectroscopy, Fourier Transform Infrared
  • Time Factors
  • Tissue Engineering / methods*

Substances

  • Biocompatible Materials
  • Melanins