Chapter 13 Molecular-based biomimetics Introduction 13.1 Self-assembly structures 13.2 Phage-enabled assembly 13.3 Genetically engineered peptides for inorganics (GEPIs) 13.4 Genetic engineering General principles and methodology Applications 13.5 Virus-assisted synthetic materials 13.6 Bioinspiration from the molecular level: the bottom-up approach 13.7 MEMS and NEMS 13.8 Bioinspired synthesis and processing of biopolymers

DNA Self-assembly More complex patterns of DNA + Metal particles DNA pairs with ‘sticky ends’ forming a regular two-dimensional pattern Seeman and Belcher, PNAS 99 (2002) 6451–6455

Periodic Au-Nanoparticle Arrays by Self-assembly Schematic representations of the formation of periodic gold nanoparticle arrays by self-assembly of cross-shaped DNA tiles with complementary sticky ends

Self-assembly of DNA nano-ribbons & nano-grids Yan H, Park SH, Finkelstein G, Reif JH, LaBean T. Science 2003;301:1882.

Self-assembled monolayers (SAMs) of alkanethiols can be formed on gold evaporated onto a solid flat substrate such as silicon or glass. The sulfur groups interact covalently with the gold, the poly(methylene) chains pack tightly to form the monolayer, and the head groups are exposed.

Near-field phototlithography with self-assembled micolenses. (From Whitesides (2002); with kind permission from Professor Whitesides.)

7 Self Assembly: T4 Phage (Virus)

Various structure assembled from viruses Flynn CE, Lee SW, Peelle BR, Belcher AM. Acta Mater 2003;51:5867.

M13 virus as anode materials for Li-ion batteries Materials-specific peptides identified by biopanning (phage display) were expressed on the major coat p8 proteins of viruses to grow Co3O4 and Au-Co3O4 nanowires. Macroscopic ordering of the engineered viruses was used to fabricate an assembled monolayer of Co3O4 nanowires for flexible, lightweight Li ion batteries. Taken from (Nam, 2006).

M13 virus with peptides which attach to nanocrystalline  -FePO4, and the gene III protein (pIII) that is engineered to have a binding affinity for SWNTs; this leads to lithium ion battery cathode that has nanostructure and therefore enables greater current density. Taken from (Lee, 2009). M13 virus as cathode for Li-ion batteries

M13 Virus grabbing a single wall CNT Source: sourhttp://news.sciencemag.org/sciencenow/2009/04/03-01.html

GEPI: Genetically Engineered Peptides for Inorganics M. Sarikaya’s University of Washington, MSE Department

Phage display and cell-surface display Sarikaya et al., Nature Materials, 2, 376 (2003).

Combinatorial Mutagenesis: Genetic Selection of Solid-Binding Peptides

GEPIs: The Bottom-up Approach Sarikaya et al., Nature Materials, 2, 376 (2003).

Inorganics-binding polypeptide Au Pt Pd Ag SiO 2 ZnO CaCO 3 Fe2O 3 ZnS Etc… Sarikaya et al., Nature Materials, 2, 376 (2003).

Resilin Unusual elastomeric protein found in insects  Ability of fleas to jump 100X their height; flies flap their wings 10 6 times/hour Millions of extensions and contractions  97% of energy stored in compression can be used for tension  Can stretch 3X original length More resilient than any synthetic material (polybutadiene) Synthetic production in E. coli 17 C.M. Elvin, et al., Nature, 437, (2005).

ATP Synthase - A Molecular Turbine ATP synthase is an important enzyme that provides energy for the cell to use through the synthesis of adenosine triphosphate (ATP) ATP is the most commonly used "energy currency" of cells from most organisms. It is formed from adenosine diphosphate (ADP) and inorganic phosphate (P i ) which releases energy. The overall reaction sequence is: ATP synthase + ADP + P i → ATP Synthase + ATP This energy is often in the form of protium or H+, moving down an electrochemical gradient, such as from the lumen into the stroma of chloroplasts or from the inter-membrane space into the matrix in mitochondria.

F 1 -ATPase as a Bio-hybrid Nanodevice Soong et al., Science, 290 (2000), 1555.

F 1 -ATPase as a Bio-hybrid Nanodevice Soong et al., Science, 290 (2000), 1555.

Electrically Driven Linear Nanomotor An indium nanocrystal ram between two carbon-nanotube lever arms. Another indium nanocrystal is attached to one of the lever arms, and through electron migration of indium atoms along the surface of the nanotubes, serves as a continuous supply of indium atoms. The voltage bias applied to the lever controls the direction of flow of indium atoms between reservoir and ram, making the ram grow or shrink, and thereby prying the lever arms apart or allowing them to relax together. Regan et al., Nano Letter, 5 (2005), 1730.

Nano-devices based on oxidation-reduction cycles Huang et al., APL, 85 (2004) 5391.

Photochemomechanical-induced Nano-devices H.F. Ji et al., Chem. Commun., (2004) 2532.

Rotary Motion of a Gold/Nickel Nanorod S. Fournior-Bidoz et al., Chem. Commun., (2005) 441.