Influence of Zinc on the Formation of Granules of Calcium Pyrophosphate

Abstract

ABSTRACTAccumulation of metals in inorganic granules is very common in invertebrates. The formation of metal deposits in both intra- and extracellular sites can be seen as a process for the detoxification of heavy metals. In barnacles, such inorganic granules usually contain calcium pyrophosphate. Incorporation of metals within such granules occurs mainly via the formation of metal pyrophosphate salts. In order to assess the chemistry of some reactions occurring during granule formation, the synthesis of calcium pyrophosphate, doped with zinc(II) ions with different [Zn]:[Ca] molar ratios, has been investigated at pH 7 and 25 °C. The thermal stability of the products was studied at different temperatures. Considerable variations occur in the structure of calcium pyrophosphate when zinc ions are present in solution in small concentrations.