Porous hydroxyapatite-dodecylphosphate composite film on titania-titanium substrate

Abstract

Synthetic analogues of bone are being actively pursued as materials for biomedical applications in the field of bone replacement, augmentation and repair. Numerous stringent criteria have to be met for a biomaterial to be considered as an acceptable bone implant, including the ability to integrate into bone and not cause any deleterious side effects. In this article we describe a materials chemistry approach to synthesizing a new type of bone implant material. The strategy involves the spontaneous growth, under aqueous physiological pH conditions, of an oriented hydroxyapatite film with micron dimension porosity, on the surface of a layer of TiO₂ that has been sputter deposited on Ti metal. This procedure creates desirable co-crystallized phases of hydroxyapatite (OHAp) and octacalcium phosphate (OCP) with preferred orientation respectively along the [00l] and [101] directions. Subsequently, a calcium dodecylphosphate mesolamellar phase has been grown within these oriented porous films to create a multilayered chemical composite CaDDP-OHAp-TiO₂-Ti in which the CaDDP phase is stereochemically and charge matched with the OHAp.

References

1. J. Vincent, in Structural Biomaterials, Princeton University Press: Princeton, 1990.
2. R. Z. LeGeros, G. Daculsi, I. Orly, T. Abergas and W. Torres, Scanning Microsc., 1989, 3, 129.
3. D. N. Misra, in Adsorption on and Surface Chemistry of Hydroxyapatite, ed. W. E. Brown, M. Mathew and L. C. Chow, Plenum Press, New York, 1984, p. 13.
4. J. C. Elliot, in Structure and Chemistry of the Apatites and Other Calcium Orthophosphates, Elsevier, New York, 1994.
5. A. A. Campbell, G. E. Fryxell, J. C. Linehan and G. L. Graff, J. Biomed. Mater. Res., 1996, 32, 111.
6. W. R. Lacefield, in Bioceramics: Material Characterizations Versus In Vivo Behavior; Ann. New York Acad. Sct., eds. P. Ducheyne and J. E. Lemons, 1988, 523, 72.
7. T. Kokubo, F. Miyaji and H. Kim, J. Am. Ceram. Soc., 1996, 79, 1127.
8. F. H. Silver, in Biomaterials, Medical Devices and Tissue Engineering, Chapman and Hall, New York, 1994.
9. T. Kokubo, Biomaterials, 1991, 12, 155.
10. P. Ducheyne and D. Christiansen, in Bioceramics 6, Butterworth-Heinemann, Oxford, 1993.
11. R. Van Noort, J. Mater. Sci., 1987, 22, 3801.
12. K. de Groot, R. G. T. Geesink, C. P. A. T. Klein and P. Serekian, J. Biomed. Mater. Res., 1987, 21, 1375.
13. T. Hanawa and M. Ota, Biomaterials, 1991, 12, 767.
14. P. Ducheyne, L. L. Hench, A. Kagan, M. Martens, A. Burssens and J. C. Mulier, J. Biomed. Mater. Res., 1980, 14, 225.
15. G. A. Ozin, N. Varaksa, N. Coombs, J. E. Davies, D. Perovic and M. Ziliox, J. Mater. Chem., 1997, 7, 1601.
16. C. Elliot, in Structure and Chemistry of the Apatites and Other Calcium Orthophosphates, Elsevier, New York, 1994.
17. C. Rey, M. Shimizu, B. Collins and M. J. Glimcher, Calcif. Tissue Int., 1990, 46, 384.
18. C. Rey, M. Shimizu, B. Collins and M. J. Glimcher, Calcif. Tissue Int., 1991, 49, 383.
19. S. R. Radin and P. Ducheyne, J. Biomed. Mater. Res., 1993, 27, 35.
20. N. Pleshko, A. Boskey and R. Mendelsohn, Biophys. J., 1991, 60, 786.
21. B. O. Fowler, M. Markovic and W. E. Brown, Chem. Mater., 1993, 5, 1417.
22. E. L. Bullock, L. Patthey and S. G. Steinemann, Surf. Sci., 1996, 352–354, 504.
23. T. K. Sham and M. S. Lazarus, Chem. Phys. Lett., 1979, 68, 426.
24. P. W. Brown and B. Constantz, Hydroxyapatite and Related Materials, CRC, Boca Raton, FL, 1994.
25. S. Sugiyama, T. Minami, T. Moriga, H. Hayashi, K. Koto, M. Tanaka and J. B. Moffat, J. Mater. Chem., 1996, 6, 459.
26. J. L. Ong, L. C. Lucas, G. N. Raikar, J. J. Weimar and J. C. Gregory, Colloids Surf. A: Physicochem. Eng. Asp., 1994, 87, 151.
27. W. P. Rothwell, J. S. Waugh and J. P. Yesinowski, J. Am. Chem. Soc., 1980, 102, 2637.
28. M. M. Crutchfield, C. F. Callis, R. R. Irani and G. C. Roth, Inorg. Chem., 1962, 4, 813.
29. D. G. Gorenstein, J. Am. Chem. Soc., 1975, 97, 898.