Nanochemistry Projects

Metabolic Engineering of Magnetic Bacteria.  In order to become applied widely across science, and ultimately industry, nanomaterials must be made in high yield in environmentally friendly ways.  One solution to this problem is to explore biosynthetic routes to inorganic nanostructures.  We propose to use metabolic engineering to understand and ultimately manipulate classes of bacteria which naturally produce inorganic nanocrystals.  By evolving these altered species we will develop strains efficient at producing nanocrystals in high yield, with specific shapes, sizes and crystal habits.   Gene splicing techniques may also provide a route for expressing specific biological receptors at the surfaces of these membrane-bound nanoparticles.  Such systems would exhibit high specificity for biological substrates, an ideal characteristic for drug delivery and tagging applications in biomedical engineering.   In addition, these studies will provide a new insight into the mechanisms by which bacteria sequester toxic metals, and will prove useful to bioremediation efforts of importance in environmental engineering.  Colvin, Parry, Matsuda, and Hughes.   

Protein-Nanocrystal Complexes in Solution.  The biological world is filled with examples of intricate enzymatic machinery for complex chemical processes.  It may someday be possible to exploit these systems for nanoscale chemistry and assembly.  However, the first step will be to study and manipulate the nanomaterial-protein interface in solution.  This research effort will form and study the binding affinity between nanostructures and proteins, particular DNA polymerase and chaperones.   In one strategy, solution phase assembly will be mediated by DNAp, a dimeric enzyme which recognizes specific sequences of DNA.  Thus DNA sequences bound to nanotubes could serve to dictate the assembly pattern around DNAp.   For more globular nanostructures, chaperones provide large circular active sites of known chemical structures.  Modern drug design programs will be used to explore how nano-object shape, size and surface chemistry can be used to produce specific binding to these sites.  In this instance, small polypeptide fragments will serve as the assembly molecules.  Binding affinitiy will be evaluate using standard biochemical methods, as well as high resolution NMR in some instances.  Smalley, Ma, MacKenzie, Matthews.

The use of molecules as structural elements provides a new way to design supramolecules capable of acting as molecular machines.  In this project area, internal molecular dipoles will provide the driving force for creating assemblies which can rotate, or in some cases even move under the action of an applied electric field.  Experimentally, the motion of these objects will be detected optically using phase-sensitive birefringence. Simulations of the self-assembly of such objects will provide for quantitative comparison between theory and experiment, and allow for the development of models to understand friction on nanometer length scales.
Tour, Smalley, Kavraki.

To contact us:

Dr. Vicki Colvin/Dr. Kristen Kulinowski
MS60 Department of Chemistry, Rice University, Houston TX 77005