Formation of composites comprised of calcium deficient HAp and cross-linked gelatin

  • Ahmed H. Touny
  • Cato Laurencin
  • Lakshmi Nair
  • Harry Allcock
  • Paul W. Brown


Cross-linked gelatin/calcium deficient hydroxyapatite (CDHAp) composites were prepared at or near physiologic temperature. α-tricalcium phosphate (α-TCP) or a mixture of tetracalcium phosphate and dicalcium phosphate were used as CDHAp precursors. Glutaraldehyde was used to cross-link the gelatin fibers. CDHAp formation reached completion in the presence of cross-linked gelatin fibers. Effects of cross-linking concentrations, proportions of gelatin fiber, molecular weight of gelatin and the temperature of the hydration reaction on the formation of CDHAp were studied. Cross-linked gelatin acts as a nucleating agent for CDHAp formation. The pH variations during CDHAp formation are lower at the onset of the reactions in the presence of cross-linked gelatin fibers. Although cross-linked gelatin fibers enhance CDHAp formation their composites have low mechanical strengths. Swelling of gelatin appears to be a major factor that limits the strengths of the CDHAp/cross-linked gelatin composites.


  1. 1.
    A. Veis, The Macromolecular Chemistry of Gelatin. (Academic Press, New York, London, 1964)Google Scholar
  2. 2.
    P.J. Rose, H.F. Mark, N.M. Bikales, C.G. Overberger, G. Menges, J.I. Kroschwitz, Encyclopedia of Polymer Science and Engineering, vol. 7, 2nd edn. (Wiley Interscience, New York, 1987)Google Scholar
  3. 3.
    M.I. Nimni, D.T. Cheung, B. Stratus, M. Kodama, K. Sheikh, Bioprosthesis derived from cross-linked and chemically modified collagenous tissues. In: Collagen, vol. 3, ed. by M.E. Nimni (CRC Press, Boca Raton, 1988), pp. 1–38Google Scholar
  4. 4.
    K. Watanabe, Y. Tezuka, T. Ishii, Configuration between re-formed collagen triple helices and artificially introduced cross-links in gelatin gels. Macromolecules 30(25), 7910–7913 (1997)CrossRefGoogle Scholar
  5. 5.
    A. Bigi, S. Panzavolta, K. Rubini, Relationship between triple-helix content and mechanical properties of gelatin films. Biomaterials 25(25), 5675–5681 (2004)CrossRefGoogle Scholar
  6. 6.
    M. Usta, D.L. Piech, R.K. MacCrone, W.B. Hillig, Behavior and properties of neat and filled gelatins. Biomaterials 24(1), 165–172 (2003)CrossRefGoogle Scholar
  7. 7.
    A. Bigi, M. Borghi, G. Cojazzi, A.M. Fichera, S. Panzavolta, N. Roveri, Structural and mechanical properties of cross-linked drawn gelatin films. J. Therm. Anal. Calorim. 61(2), 451–459 (2000)CrossRefGoogle Scholar
  8. 8.
    C. Yao, B. Liu, C. Chang, S. Hsu, Y. Chen, Preparation of networks of gelatin and genipin as degradable biomaterials. Mater. Chem. Phys. 83, 204–208 (2004)CrossRefGoogle Scholar
  9. 9.
    C. Michon, G. Cuvelier, P. Relkin, B. Launay, Influence of thermal history on the stability of gelatin gels. Int. Biol. Macromol. 20, 259 (1997)CrossRefGoogle Scholar
  10. 10.
    A.N. Fraga, R.J. Williams, Thermal properties of gelatin films. Polymer 26(1), 113–118 (1985)CrossRefGoogle Scholar
  11. 11.
    A.A. Apostolov, D. Boneva, E. Vassileva, J.E. Mark, S. Fakirov, Mechanical properties of native and cross-linked gelatins in a bending deformation. J. Appl. Poly. Sci. 76(14), 2041–2048 (2000)CrossRefGoogle Scholar
  12. 12.
    K. Terao, T. Karino, N. Nagasawa, F. Yoshii, M. Kubo, T. Dobashi, Gelatin microspheres cross-linked with γ-ray: preparation, sorption of proteins, and biodegradability. J. Appl. Poly. Sci. 91(5), 3083–3087 (2004)CrossRefGoogle Scholar
  13. 13.
    G. Goissis, E.M. Junior, R.A.Ch. Marcantonio, R.C.C. Lia, D.C.J. Cancian, W.M. De Carvalho, Biocompatibility studies of anionic collagen membranes with different degree of glutaraldehyde cross-linking. Biomaterials 20(1), 27–34 (1999)CrossRefGoogle Scholar
  14. 14.
    C. Yao, J. Sun, F. Lin, C. Liao, C. Huang, Biological effects and cytotoxicity of tricalcium phosphate and formaldehyde cross-linked gelatin composite. Mater. Chem. Phys. 45(1), 6–14 (1996)CrossRefGoogle Scholar
  15. 15.
    J. Draye, B. Delaey, A. Van de Voorde, A. Bulcke, E. Etienne Schacht, In vitro release characteristics of bioactive molecules from dextran dialdehyde cross-linked gelatin hydrogel films. Biomaterials 19(1–3), 99–107 (1998)CrossRefGoogle Scholar
  16. 16.
    S.R. Jameela, A. Jayakrishnan, Glutaraldehyde cross-linked chitosan microspheres as a long acting biodegradable drug delivery vehicle: studies on the in vitro release of mitoxantrone and in vivo degradation of microspheres in rat muscle. Biomaterials 16(10), 769–775 (1995)CrossRefGoogle Scholar
  17. 17.
    J.M. McPherson, S. Sawamura, R. Armstrong, Examination of the biologic response to injectable, glutaraldehyde cross-linked collagen implants. J. Biomed. Mater. Res. 20(1), 93–107 (1986)CrossRefGoogle Scholar
  18. 18.
    M. Kikuchi, H.N. Matsumoto, T. Yamada, Y. Koyama, K. Takakuda, J. Tanaka, Glutaraldehyde cross-linked hydroxyapatite/collagen self-organized nanocomposites. Biomaterials 25(1), 63–69 (2004)CrossRefGoogle Scholar
  19. 19.
    K. Eugene, Methods for the treatment of collagenous tissues for bioprostheses. Biomaterials 18(2), 95–105 (1997)CrossRefGoogle Scholar
  20. 20.
    D. Lickorish, J. Ramshaw, J. Werkmeister, V. Glattauer, C.R. Howlett, Collagen-hydroxyapatite composite prepared by biomimetic process. J. Biomed. Mater. Res.—Part A. 68(n), 19–27 (2004)CrossRefGoogle Scholar
  21. 21.
    L.H. Damink, P.J. Dijkstra, M.J.A. Van Luyn, P.B. Van Wachem, P. Nieuwenhuis, J. Feijen, Glutaraldehyde as a crosslinking agent for collagen-based biomaterials. J. Mater. Sci. Mater. Med. 6(8), 460–472 (1995)CrossRefGoogle Scholar
  22. 22.
    M.R. Ahmed, U. Venkateshwarlu, R. Jayakumar, Multilayered peptide incorporated collagen tubules for peripheral nerve repair. Biomaterials 25(13), 2585–2594 (2004)CrossRefGoogle Scholar
  23. 23.
    S. Matsuda, H. Iwata, N. Se, Y. Ikada, Bioadhesion of gelatin films crosslinked with glutaraldehyde. J. Biomed. Mater. Res. 45(1), 20–27 (1999)CrossRefGoogle Scholar
  24. 24.
    A. Bigi, S. Panzavolta, N. Roveri, Hydroxyapatite-gelatin films: a structural and mechanical characterization. Biomaterials 19(7–9), 739–744 (1998)CrossRefGoogle Scholar
  25. 25.
    A.A. Apostolov, S. Fakirov, E. Vassileva, R.D. Patil, J.E. Mark, DSC and TGA studies of the behavior of water in native and crosslinked gelatin. J. Appl. Poly. Sci. 71(3), 465–470 (1999)CrossRefGoogle Scholar
  26. 26.
    M.B.Yaylaoglu, P. Korkusuz, U. Örs, F. Korkusuz, V. Hasirci, Development of a calcium phosphate-gelatin composite as a bone substitute and its use in drug release. Biomaterials 20(8), 711–719 (1999)CrossRefGoogle Scholar
  27. 27.
    Lj. Brecevic, V. Hlady, H. Fueredi-Milhofer, Influence of gelatin on the precipitation of amorphous calcium phosphate. Colloids Surf. 28(2–4), 301–313 (1987)CrossRefGoogle Scholar
  28. 28.
    T. Chen, C. Yao, H. Wang, G. Chou, T. Lee, F. Lin, Evaluation of a novel malleable, biodegradable osteoconductive composite in a rabbit cranial defect model. Mater. Chem. Phys. 55(1), 44–50 (1998)CrossRefGoogle Scholar
  29. 29.
    A. Bigi, S. Panzavolta, N. Roveri, Hydroxyapatite-gelatin films: a structural and mechanical characterization. Biomaterials 19(7–9), 739–744 (1998)CrossRefGoogle Scholar
  30. 30.
    M. Chang, C. Ko, W.H. Douglas, Preparation of hydroxyapatite-gelatin nano-composite. Biomaterials 24(17), 2853–2862 (2003)CrossRefGoogle Scholar
  31. 31.
    K.S. Tenhuisen, P.W. Brown, The formation of hydroxyapatite-gelatin composites at 38°C. J. Biomed. Mater. Res. 28(1), 27–33 (1994)CrossRefGoogle Scholar
  32. 32.
    C. Yao, F. Lin, C. Huang, C. Wang, Biological effects and cytotoxicity of the composite combined with tricalcium phosphate and glutaraldehyde crosslinked gelatin for orthopedic application. in Annual International Conference of the IEEE Engineering in Medicine and Biology—Proceedings, vol. 5, 1996, pp. 2042–2043Google Scholar
  33. 33.
    A. Bigi, B. Bracci, S. Panzavolta, Effect of added gelatin on the properties of calcium phosphate cement. Biomaterials 25(14), 2893–2899 (2004)CrossRefGoogle Scholar
  34. 34.
    A. Bigi, B. Bracci, S. Panzavolta, Influence of gelatin on the setting properties of α-tricalcium phosphate cement. Key Eng. Mater. 254–256, 229–232 (2004)CrossRefGoogle Scholar
  35. 35.
    M.B. Thomas, R.H. Doremus, M. Jarcho, R.L. Salsbury, Dense hydroxyapatite: fatigue and fracture strength after various treatments, from diametrical tests. J. Mater. Sci. 15, 891–894 (1980)CrossRefGoogle Scholar
  36. 36.
    A. Rutanick, A.R. Hunter, F.C. Holden, An analysis of the diametrical compression test. Mater. Res. Standards 3, 283–289 (1963)Google Scholar
  37. 37.
    A. Bigi, B. Bracci, G. Cojazzi, S. Panzavolta, N. Roveri, Drawn gelatin films with improved mechanical properties. Biomaterials 19(24), 2335–2340 (1998)CrossRefGoogle Scholar
  38. 38.
    A. Bigi, G. Cojazzi, S. Panzavolta, K. Rubini, N. Roveri, Mechanical and thermal properties of gelatin films at different degrees of glutaraldehyde cross-linking. Biomaterials 22(8), 763–768 (2001)CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  • Ahmed H. Touny
    • 1
  • Cato Laurencin
    • 2
  • Lakshmi Nair
    • 2
  • Harry Allcock
    • 3
  • Paul W. Brown
    • 1
  1. 1.Department of Materials Science and EngineeringPenn State UniversityUniversity ParkUSA
  2. 2.Department of Orthopedic SurgeryUniversity of VirginiaCharlottesvilleUSA
  3. 3.Department of ChemistryPenn State UniversityUniversity ParkUSA

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