Synthesizing a composite material of amorphous calcium carbonate and aspartic acid

Abstract A composite material of amorphous calcium carbonate and aspartic acid (Asp) was synthesized using a highly concentrated solution of calcium aspartate: a new approach. A transparent and amorphous solid with approximately 1 mm thickness was obtained. UV–vis transmittance spectrum of the composite shows no characteristic absorption in visible region. A Raman spectrum of the composite revealed a peak assigned to the symmetric stretching of carbonate ion. This study demonstrated that amorphous calcium carbonate could be stabilized using not only organic artificial macromolecules but also using Asp, a small biomolecule. This result is expected to engender development of new biomimetic materials.