Biogenic synthesis of hierarchical hybrid nanocomposites and patterning of silver nanoparticles

Evolvement of bio-inspired approaches for the construction of well-ordered nanocomposites is a crucial intersectant branch of materials science and biotechnology. In this paper, floriated clusters of silver nanocrystallites consisted of polycrystalline grains of 5-10 nm in diameter, have been successfully prepared on silk fibroin fibers (SFF) through a biotemplate redox approach at room temperature. The reductive amino acid tyrosine of SFF mainly provided both reduction and location functions under alkaline conditions, could reduce Ag(I) ions to Ag(O), finally stable silver particles were generated on the SFF substrates. Thus, small-sized but well-crystallized silver nanocrystallites could associate with the biosubstrate SFF to be organized into subtle hierarchy, as a result to form inorganic-organic hybrids under the direction of the SFF biomacromolecules. The morphologies of silver nanoparticles were mostly attributed to the concentration of silver nitrate solution as well as special configurations and structures of SFF macromolecules. This study represents an important advance in the use of biofibers in the synthesis of hierarchical functional hybrid nanocomposites by a green and mild technique. (C) 2008 Elsevier B.V. All rights reserved.