Biomimetic Synthesis of Calcium Carbonate with the Assistance of Amino Acids

Abstract

Two acidic amino acids (aspartic acid, glutamic acid) and four neutral amino acids (cysteine, serine, tyrosine, glycine) were used as inducers for calcium carbonate biomimetic synthesis. The results showed that aspartic acid introduced is more effective for the growth of aragonite, while glutamic acid used is more effective for the growth of vaterite. Compared to those acidic amino acids, neutral amino acids used lead to less aragonite or vaterite produced, and tyrosine and serine show stronger effects on the growth of aragonite and vaterite than cysteine and glycine. On the other hands, it was found that the increased concentration of amino acid shows positive effects on the growth of aragonite and vaterite. In addition, the enhanced concentration of calcium chloride results in the increased crystalline volume of calcite significantly, as well as the more orderly structure as shown in scanning electron microscopy investigation. Meanwhile, the high calcium chloride concentration indicates weak inhibitory effect on aragonite growth but no significant influence on the growth of vaterite.