Apatite formation

Ruttenberg, K. C. and Berner, R. A. (1993). Authigenic apatite formation and burial in sediments from non-upwelling, continental margin environments. Geochim. Cosmochim. Acta 57,991-1007. 

Apatite formation on/in hydrogel matrixes using an alternate soaking process II. Effect of swelling ratios of poly(vinyl alcohol) hydrogel matrixes on apatite formation. Journal of Biomaterials Science-Polymer Edition, 10, 331-339. 

Taguchi, T., Kishida, A. and Akashi, M. (1999) Apatite formation on/in hydrogel matrices using an alternate soaking process (III) effect of physico-chemical factors on apatite formation on/in poly (vinyl alcohol) hydrogel matrices. Journal of Biomaterials Science—Polymer Edition, 10, 795-804. 

Cho, S.B., Nakanishi, K., Kokubo, T., Soga, N., Ohtsuki, C., Nakamura, T., Kitsugi, T. and Yamamuro, T. (1995) Dependence of apatite formation on silica gel on its structure effect of heat treatment Journal of the American Ceramic Society, 78, 1769—1774. 

Uchida, M., Kim, H.-M., Kokubo, T., Fujibayashi, S. and Nakamura, T. (2003) Structural dependence of apatite formation on titania gels in a simulated body fluid. Journal of Biomedical Materials Research, 64A, 164-170. 

Kim, H.-M., Uenoyama, M., Kokubo,T., Minoda, M., Miyamoto, T. and Nakamura, T. (2001)Biomimetic apatite formation on polyethylene photografted with vinyltrimethoxysilane and hydrolyzed. Biomaterials, 22, 2489-2494. 

Chen, Q., Miyaji, F., Kokubo, T. and Nakamura, T. (1999) Apatite formation on PDMS-modified Ca0-Si02-Ti02 hybrids prepared by sol-gel process. Biomaterials, 20, 1127—1132. 

Jahn, T. L. A possible mechanism of the effect of electrical potentials on apatite formation in bone. Clin. Orthop. 56, 261 (1968)... 

Yasuda, I. and Hishinuma, M., Electrical conductivity and chemical stability of calcium chromate hydroxyl apatite, Cas(Cr04)30H, and problems caused by the apatite formation at the electrode/separator interface in solid oxide fuel cells, Solid State Ionics 80, 1995, 141. 

Chemisorption raises basic questions for the carbonate geochemist about the boundary between sorption and coprecipitation. If the adsorption reaction takes place in a solution that is also supersaturated with respect to the carbonate mineral substrate, then the adsorbed ions can be buried in the growing layers of the mineral and become coprecipitates. This mechanism can result in distribution coefficients that are dependent on growth rates. Also, when chemisorption is involved, an entirely new phase or a coprecipitate can form in the near-surface region of the carbonate (e.g., see Morse, 1986 Davis et al 1987). A classic example is apatite formation on calcite in dilute solutions (e.g., Stumm and Leckie, 1970). 

Gaudette, H.E., and Lyons, W.B. (1980) Phosphate geochemistry in nearshore carbonate sediments suggestion of apatite formation. Soc. Econ. Paleon. Min. Spec. Publ. 29, 215-225. 

Krajewski, K.P., van Cappellen, P., Trichet, J., Kuhn, O., Lucas, J., Martin-Algarra, A., Prevot, L., Tewari, V.C., Caspar, L., Knight, R.I., and Lamboy, M. (1994) Biological processes and apatite formation in sedimentary environments. Ecol. Geol. Helv. 87, 701-745. 

Slomp, C.P., Epping, E.H., Helden, W., and Raaphorst, W.V. (1996) A key role for iron-bound phosphorus in authigenic apatite formation in North Atlantic continental platform sediments. J. Mar. Res. 54, 1179-1205. 

Experimental studies of authigenic apatite precipitation. Mechanisms and rates of authigenic apatite formation in the early diagenetic environment are difficult to resolve, because of the wide variety of biological, chemical, and physical factors that can affect its formation. Experimental studies of apatite formation under controlled conditions have provided important information for placing constraints on modes and rates of CEA authigenesis. Examples of such studies include those of Ames (1959), who documented nucleation of CEA on calcium carbonate Gulbrandsen et al. (1984), who documented rates of CEA formation in seawater Jahnke (1984), who evaluated the... 

Sato, K., Kumagai, Y., and Tanaka, J., Apatite formation on organic monolayers in simulated body environment. J. Biomed. Mater. Res., 50, 16, 2000. 

Fig. 16.6 Hydroxyapatite and fluoroapatite formation and dissolution, (a) Hydroxyapatite is transformed to fluoroapatite by isomorphous replacement. Fluoride ions diffuse into a hydroxyapatite crystal where they replace the hydroxide ions, (b) Fluoroapatite cannot dissolve as easily as hydroxyapatite. Right to left shows the solid-state rearrangement of hydroxyapatite to calcium monohydrogen phosphate, free calcium ions, and monohydrogen phosphate. The latter becomes mostly dihydrogen phosphate above pH 6.2. Arrows between (b) and (a) indicate enhanced apatite formation or slower changes to the amorphous solid if fluoride is present. Left to right shows the precipitation of calcium monohydrogen phosphate and its change to hydroxyapatite if an acid solution is made alkaline.

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