Poster Presentation 2-26

 

Biopolymer-Patterned Nanoparticle Deposition

 

 

S. A. Hutchens,3 H. M. O’Neill,1,2* B. R. Evans,2 J. Y. Howe4 and M.Z. Martin5

 

 

1Department of Biochemistry & Molecular & Cellular Biology

University of Tennessee

Knoxville, TN 37996-0840

 

2Chemical Sciences Division

Oak Ridge National Laboratory

Oak Ridge, TN 37831-6194

Phone:  (865)574-5004

Fax:  (865)574-1275

E-mail:  oneillhm@ornl.gov

 

3Department of Biomedical Engineering, University of Tennessee

 

4Metals and Ceramics Division, Oak Ridge National Laboratory

 

5Environmental Sciences Division, Oak Ridge National Laboratory

 

 

 

Spatial constraints, high localized concentrations, targeted catalysis, and specific crystallization initiation sites are key determining factors in the formation of natural biominerals such as bone, shell, phytoliths, and diatomaceous silica.  To successfully carry out biomimetic formation of nanopatterned minerals and metals, these properties must be replicated under controlled conditions.  The biopolymer cellulose, particularly in the sponge-like hydrophilic form produced by Gluconoacetobacter spp., provides a suitable matrix for the nucleation and deposition of a number of minerals and metals that are of interest for technological applications.  The cellulose itself possesses hydroxyl and aldehyde groups that can modulate and initiate particulate formation. Several types of catalytic groups can be incorporated into the polymer backbone to enable targeted deposition of specific materials. Serial infusions of soluble precursors and reactants are easily carried out.  Bacterial culture conditions modulate the size, shape, porosity, and thickness of the cellulose matrix used for biopatterned deposition. The size and composition of metal and ceramic particles formed within the cellulose matrix can be readily determined by tunneling electron microscopy (TEM), infrared spectroscopy (IR), laser-induced breakdown spectroscopy (LIBS), and X-ray diffraction.  Specific examples include deposition of crystalline palladium nanoparticles and formation of pure calcium deficient hydroxyapatite.