Assembly of nano-superstructural aragonite CaCO3 by living bio-membrane

Biomimetic living templates, mung bean sprouts (MBS), were employed to control the crystallisation of calcium carbonate. Metastable aragonite superstructure can be readily generated in normal conditions. Some interesting morphologies including elaborate piny dendritic, flowerlike and rods were also prepared using citric acid, nitrilotriacetic acid and ethylenediaminetetraacetic acid as cooperation modifiers in the mineralisation process, under the conditions of 0.01% of crystal modifier and ambient temperature. These morphologies were assembled by some elaborate substructures, similar to nanowire and featherlike crystals. The products were characterised by SEM, XRD and FTIR, respectively. The results indicated that the formation of aragonite polymorph of calcium carbonate was favoured in this system. A probable mechanism was proposed.