title: Control over the crystal phase, shape, size and aggregation of calcium carbonate via a L-aspartic acid inducing process.
abstract: The acidic amino acid, such as aspartic acid (l-Asp), and glutamic acid are the primary active molecules of the glycoprotein on the organic/inorganic interface of biomineralized tissue. In this study, aspartic acid was used as the organic template in inducing the nucleation and growth of calcium carbonate. With the analysis of X-ray diffraction we investigated the relationship between the l-Asp concentration and the precipitation phase crystal structure of calcium carbonate. SEM and TEM were employed in the analysis of the morphological characteristic of the precipitation and the aggregation of the nanoscale porous phase. In order to get the direct evidence of the interaction between Ca2+ and l-Asp, the technique of QCM was used in the investigation of the coordinate interaction of Ca2+/l-Asp. As the results have shown, l-Asp alone is adequate to switch the transformation between calcite and vaterite, and neither soluble organic additions nor metal ions are needed. Meanwhile, the morphology, size and aggregative way of the deposition are also mediated with change of l-Asp concentration. To interpret the cause of the hierarchic structure range from nanoscale to micron-scale and the formation of the porous spheres of vaterite, an assumption of limited-fusion was proposed from the view of the small biomolecules polarity that can control over the growth of the crystals and the aggregation of the micro crystals. The conclusion also provide a new material synthesize strategy.
authors.affiliation: College of Molecular Science and Chemistry, Wuhan Univeristy, Wuhan Hubei 430072, PR China. tonghua@whu.edu.cn
authors.forename: Hua
authors.initials: H
authors.lastname: Tong
authors.forename: Wentao
authors.initials: W
authors.lastname: Ma
authors.forename: Leilei
authors.initials: L
authors.lastname: Wang
authors.forename: Peng
authors.initials: P
authors.lastname: Wan
authors.forename: Jiming
authors.initials: J
authors.lastname: Hu
authors.forename: Lianxin
authors.initials: L
authors.lastname: Cao
mesh_terms: D000327:Adsorption; D001224:Aspartic Acid / Q000737:chemistry*; D002119:Calcium Carbonate / Q000032:analysis / Q000737:chemistry*; D011232:Chemical Precipitation; D020099:Coated Materials, Biocompatible / Q000032:analysis / Q000737:chemistry*; D003460:Crystallization / Q000379:methods*; D004563:Electrochemistry / Q000379:methods*; D046911:Macromolecular Substances; D008422:Materials Testing; D008968:Molecular Conformation; D043942:Nanotubes / Q000032:analysis / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D044367:Phase Transition; D016062:Porosity; D012996:Solutions; D013499:Surface Properties
chemical_list: D020099:Coated Materials, Biocompatible; D046911:Macromolecular Substances; D012996:Solutions; D001224:Aspartic Acid; D002119:Calcium Carbonate