Biomimetic Assembly of Polypeptide-Stabilized CaCO3 Nanoparticles

• Published in: The journal of physical chemistry. B Vol. 110; no. 17; pp. 8613 - 8618
• Main Authors: Zhang, Zhongping, Gao, Daming, Zhao, Hui, Xie, Chenggen, Guan, Guijian, Wang, Dapeng, Yu, Shu-Hong
• Format: Journal Article
• Language: English
• Published: American Chemical Society 04.05.2006
• ISSN: 1520-6106; 1520-5207
• DOI: 10.1021/jp060838u

In this paper, we report a simple polypeptide-directed strategy for fabricating large spherical assembly of CaCO3 nanoparticles. Stepwise growth and assembly of a large number of nanoparticles have been observed, from the formation of an amorphous liquidlike CaCO3-polypeptide precursor, to the crystallization and stabilization of polypeptide-capped nanoparticles, and eventually, the spherical assembly of nanoparticles. The “soft” poly(aspartate)-capping layer binding on a nanoparticle surface resulted in the unusual soft nature of nanoparticle assembly, providing a reservoir of primary nanoparticles with a moderate mobility, which is the basis of a new strategy for reconstructing nanoparticle assembly into complex nanoparticle architectures. Moreover, the findings of the secondary assembly of nanoparticle microspheres and the morphology transformation of nanoparticle assembly demonstrate a flexible and controllable pathway for manipulating the shapes and structures of nanoparticle assembly. In addition, the combination of the polypeptide with a double hydrophilic block copolymer (DHBC) allows it to possibly further control the shape and complexity of the nanoparticle assembly. A clear perspective is shown here that more complex nanoparticle materials could be created by using “soft” biological proteins or peptides as a mediating template at the organic−inorganic interface.