Calciumphosphat

Calciumphosphate refers to a group of calcium salts of phosphoric acid. The best known members are hydroxyapatite (Ca10(PO4)6(OH)2), tricalcium phosphate (Ca3(PO4)2) and dicalcium phosphate (CaHPO4). These compounds share a common Ca–PO4 chemistry and vary in solubility, crystallinity and hydration.

In nature, calcium phosphate minerals are major components of vertebrate bones and teeth, where hydroxyapatite forms the mineral phase, often with carbonate and other substitutions. Calcium phosphate minerals also occur in geological deposits and can be produced synthetically.

Calcium phosphate can be produced by precipitation from calcium and phosphate ions in aqueous solution or by reactions of calcium salts with phosphoric acid. In manufacturing, tailored forms such as hydroxyapatite, tricalcium phosphate, and amorphous calcium phosphate are produced for biomedical and industrial uses. Hydroxyapatite is particularly important as a biomaterial due to its biocompatibility and osteoconductivity.

Applications include bone graft substitutes and bone cements in orthopedics and dentistry, dental remineralization products, and various calcium supplements. Food-grade calcium phosphate salts (as E341) are used as calcium fortification and anti-caking agents, while calcium phosphates also serve as fertilizers and feed additives.

Safety and environmental considerations: calcium phosphate compounds are poorly soluble and generally regarded as safe when used appropriately. Over-supplementation can lead to imbalances or calcifications; mining and processing have environmental footprints.