Biomimetic processing of calcium phosphate coating

Most ceramics used in surgical implantation are better tolerated by the body environment than other biomaterials, particularly metals. However, the broader application of ceramics is limited because they are brittle and prone to catastrophic failure. By contrast, naturally produced ceramic organic biocomposites can possess mechanical properties which make them suitable for use as biomaterials. An example would be the mollusc shell, where an inorganic phase grows onto a charged and organised organic template. This natural biomineralization provides a calcium carbonate phase with satisfactory mechanical properties appropriate for surgical implantation. It is reported how Langmuir Blodgett films have been used as organic templates for calcium phosphate crystallization. Three different Langmuir Blodgett Films: omega tricosenoic acid, stearic acid and octadecylamine have been investigated. The Langmuir Blodgett Films produced had methyl (CH3) and calcium carboxylate (CaCOO) as functional groups. Atomic force microscopy and scanning electron microscopy shows that calcium phosphate crystallization occurs in a similar manner to natural biomineralization. The calcium carboxylate head group appears to have a physical influence on the morphology and distribution of the calcium phosphate crystals. Under the experimental conditions tested, the calcium carboxylate functional head group controls calcium phosphate crystallization by a biomimetic approach. This study strongly suggests that this approach has the potential for producing high performance ceramics comparable with those made by mollusc shells. (C) 1998 IPEM. Published by Elsevier Science Ltd. Ail rights reserved.