Growth of hierarchical calcium carbonate crystals templated by biomolecules of lotus root.

In this paper, crystal growth of calcium carbonate CaCO3 in the presence of biomolecules of lotus root was investigated. Scanning electron microscopy, Fourier transform infrared spectroscopy and Xray powder diffractometry were used to characterize the products. The results indicate that calcite spherical particles were constructed from small rhombohedral subunits. Similar CaCO3crystals were also gained when crystal growth of CaCO3in aqueous solution containing extracts of lotus root was performed, suggesting that the soluble biomolecules of lotus root play a crucial role in directing the formation of hierarchical calcite spherical particles. The possible formation mechanism of the CaCO3crystals by using lotus root is also discussed, which can be interpreted by particleaggregation based nonclassical crystallization laws. The biomolecules of lotus root might induce and control the nucleation and growth of calcium carbonate crystals. © 2009 WILEYVCH Verlag GmbH & Co. KGaA, Weinheim [ABSTRACT FROM AUTHOR]