Transformation behaviour of calcium phosphate 2. Effects of various phosphorylated amino acids
Wong ATC., Czernuszka JT.
A constant composition study of the effect of phosphorylated amino acids on the precipitation of calcium phosphate has been made. It has been shown that enhancement or inhibition of precipitation rates and transformation rates from precursor phases can occur depending on the phospho-amino acid. Enhancement was facilitated by sterically accessible organic molecules and by phosphoryl groups of enhanced electronegativity. A modified Avrami-Johnson-Mehl model has been used to explain this behaviour. The complexation tendencies of the phospho-amino acids with calcium ions increase with a decrease in molecular mass and steric accessibility. Precipitation was found to have involved interface-controlled growth without any saturation of potential nucleation sites. © 1995.