Hybrid bone implants: Self-assembly of peptide amphiphile nanofibers within porous titanium

Timothy D. Sargeant, Mustafa O. Guler, Scott M. Oppenheimer, Alvaro Mata, Robert L. Satcher, David C. Dunand, Samuel I Stupp

Research output: Contribution to journalArticle

166 Citations (Scopus)

Abstract

Over the past few decades there has been great interest in the use of orthopedic and dental implants that integrate into tissue by promoting bone ingrowth or bone adhesion, thereby eliminating the need for cement fixation. However, strategies to create bioactive implant surfaces to direct cellular activity and mineralization leading to osteointegration are lacking. We report here on a method to prepare a hybrid bone implant material consisting of a Ti-6Al-4V foam, whose 52% porosity is filled with a peptide amphiphile (PA) nanofiber matrix. These PA nanofibers can be highly bioactive by molecular design, and are used here as a strategy to transform an inert titanium foam into a potentially bioactive implant. Using scanning electron microscopy (SEM) and confocal microscopy, we show that PA molecules self-assemble into a nanofiber matrix within the pores of the metallic foam, fully occupying the foam's interconnected porosity. Furthermore, the method allows the encapsulation of cells within the bioactive matrix, and under appropriate conditions the nanofibers can nucleate mineralization of calcium phosphate phases with a Ca:P ratio that corresponds to that of hydroxyapatite. Cell encapsulation was quantified using a DNA measuring assay and qualitatively verified by SEM and confocal microscopy. An in vivo experiment was performed using a bone plug model in the diaphysis of the hind femurs of a Sprague Dawley rat and examined by histology to evaluate the performance of these hybrid systems after 4 weeks of implantation. Preliminary results demonstrate de novo bone formation around and inside the implant, vascularization around the implant, as well as the absence of a cytotoxic response. The PA-Ti hybrid strategy could be potentially tailored to initiate mineralization and direct a cellular response from the host tissue into porous implants to form new bone and thereby improve fixation, osteointegration, and long term stability of implants.

Original languageEnglish
Pages (from-to)161-171
Number of pages11
JournalBiomaterials
Volume29
Issue number2
DOIs
Publication statusPublished - Jan 2008

Fingerprint

Nanofibers
Amphiphiles
Titanium
Self assembly
Peptides
Bone
Bone and Bones
Foams
Porosity
Confocal Microscopy
Confocal microscopy
Electron Scanning Microscopy
Encapsulation
Diaphyses
Dental Implants
Tissue
Durapatite
Bone cement
Dental prostheses
Scanning electron microscopy

Keywords

  • Bone
  • Foam
  • MC3T3-E1
  • Self-assembly
  • Ti-6Al-4V
  • Tissue engineering

ASJC Scopus subject areas

  • Biotechnology
  • Bioengineering
  • Biomedical Engineering

Cite this

Sargeant, T. D., Guler, M. O., Oppenheimer, S. M., Mata, A., Satcher, R. L., Dunand, D. C., & Stupp, S. I. (2008). Hybrid bone implants: Self-assembly of peptide amphiphile nanofibers within porous titanium. Biomaterials, 29(2), 161-171. https://doi.org/10.1016/j.biomaterials.2007.09.012

Hybrid bone implants : Self-assembly of peptide amphiphile nanofibers within porous titanium. / Sargeant, Timothy D.; Guler, Mustafa O.; Oppenheimer, Scott M.; Mata, Alvaro; Satcher, Robert L.; Dunand, David C.; Stupp, Samuel I.

In: Biomaterials, Vol. 29, No. 2, 01.2008, p. 161-171.

Research output: Contribution to journalArticle

Sargeant, TD, Guler, MO, Oppenheimer, SM, Mata, A, Satcher, RL, Dunand, DC & Stupp, SI 2008, 'Hybrid bone implants: Self-assembly of peptide amphiphile nanofibers within porous titanium', Biomaterials, vol. 29, no. 2, pp. 161-171. https://doi.org/10.1016/j.biomaterials.2007.09.012
Sargeant TD, Guler MO, Oppenheimer SM, Mata A, Satcher RL, Dunand DC et al. Hybrid bone implants: Self-assembly of peptide amphiphile nanofibers within porous titanium. Biomaterials. 2008 Jan;29(2):161-171. https://doi.org/10.1016/j.biomaterials.2007.09.012
Sargeant, Timothy D. ; Guler, Mustafa O. ; Oppenheimer, Scott M. ; Mata, Alvaro ; Satcher, Robert L. ; Dunand, David C. ; Stupp, Samuel I. / Hybrid bone implants : Self-assembly of peptide amphiphile nanofibers within porous titanium. In: Biomaterials. 2008 ; Vol. 29, No. 2. pp. 161-171.
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