Hot off the presses! Apr 01 Nano Today

The Apr 01 issue of the Nano Today is now up on Pubget (About Nano Today): if you're at a subscribing institution, just click the link in the latest link at the home page. (Note you'll only be able to get all the PDFs in the issue if your institution subscribes to Pubget.)

Latest Articles Include:

• Editorial Board
  - Nano Today 4(2):CO2 (2009)
  
• Weathering the risks of quantum dots
  - Nano Today 4(2):107-108 (2009)
  
• Nanowires on the line
  - Nano Today 4(2):108 (2009)
  
• A bit of a gas
  - Nano Today 4(2):109 (2009)
  
• Microscopy shows the strain
  - Nano Today 4(2):110 (2009)
  
• Bulk metallic glasses break the mold
  - Nano Today 4(2):111 (2009)
  
• Time for a new start
  - Nano Today 4(2):112-113 (2009)
  The National Research Council (NRC), which carries out studies for the U.S. National Academies, released a scathing report in December that highlights the shortfalls of the Bush administration's effort to determine the environment, health and safety (EHS) risks posed by engineered nanomaterials – a backbone of worldwide innovation. The NRC report, which was authored by an independent body of experts, highlights how understanding risks will help foster innovation. The NRC report is – if nothing else – an ideal opportunity for a new start.
• Engineered nanomaterials: Where they go, nobody knows
  - Nano Today 4(2):114-115 (2009)
  
• New pathway for self-assembly and emergent properties
  - Nano Today 4(2):116-124 (2009)
  One of the great challenges in nanotechnology is the programmed control of hierarchical self-assembly of nanoscale components to achieve specifically desired three-dimensional structures and their associated functionalities. Analysis of these processes in a biomolecular system reveals a previously unanticapated pathway for the genetically encoded control of hierarchical assembly of nanoscale components and the resultant emergence of complex behaviors.
• Simultaneous non-invasive analysis of DNA condensation and stability by two-step QD-FRET
  - Nano Today 4(2):125-134 (2009)
  Nanoscale vectors comprised of cationic polymers that condense DNA to form nanocomplexes are promising options for gene transfer. The rational design of more efficient nonviral gene carriers will be possible only with better mechanistic understanding of the critical rate-limiting steps, such as nanocomplex unpacking to release DNA and degradation by nucleases. We present a two-step quantum dot fluorescence resonance energy transfer (two-step QD-FRET) approach to simultaneously and non-invasively analyze DNA condensation and stability. Plasmid DNA, double-labeled with QD (525 nm emission) and nucleic acid dyes, were complexed with Cy5-labeled cationic gene carriers. The QD donor drives energy transfer stepwise through the intermediate nucleic acid dye to the final acceptor Cy5. At least three distinct states of DNA condensation and integrity were distinguished in single particle manner and within cells by quantitative ratiometric analysis of energy transfer efficiencies! . This novel two-step QD-FRET method allows for more detailed assessment of the onset of DNA release and degradation simultaneously.
• Superhydrophobic nanoporous polymers as efficient adsorbents for organic compounds
  - Nano Today 4(2):135-142 (2009)
  Superhydrophobic nanoporous polydivinylbenzene materials are successfully synthesized by a novel solvothermal route. The synthesized polymers exhibit high surface area, large pore volume, controllable average pore size, superhydrophobicity and superoleophilicity. In the adsorption of typical volatile organic compounds (VOC) and organic pollutants in water, it displays excellent adsorptive property compared with that of activated carbon and Amberlite XAD-4 resin. The nanoporous polydivinylbenzene almost does not adsorb either liquid or gaseous water and thus has a preferential selectivity for organic compounds. Our nanoporous material shows a great potential in air purification, wastewater treatment, chemical accident remediation and environmental protection.
• Designer platinum nanoparticles: Control of shape, composition in alloy, nanostructure and electrocatalytic property
  - Nano Today 4(2):143-164 (2009)
  Recent advances in the design and preparation of platinum-based nanostructures and their applications as electrocatalysts for low-temperature fuel cells are reviewed. Discussions are focused on the fundamental understanding and new experimental designs in the control of shape, composition and nanoscale structure of platinum and its alloy particles in colloidal systems. We explain the formation of various heteronanostructures using the Frank–van der Merwe (FM), Volmer–Weber (VW) and Stranski–Krastanov (SK) growth modes. Phenomena that exist in nanometer-sized regime, such as the disappearance of miscibility gaps for certain platinum alloys are given special attentions. The relationship between electronic structure or surface atomic arrangement and catalytic properties of platinum-based nanostructures is discussed.
• Mesoporous materials for encapsulating enzymes
  - Nano Today 4(2):165-179 (2009)
  The unique properties of mesoporous silica (MPS) materials were utilized to immobilze enzymes: huge surface area, modifiable surface, and restricted pore nanospaces. The enzyme confinements in the nanochannels of MPS materials generate synergistic effects that enhance enzyme stability, improve product selectivity, and facilitate separation and reuse of enzymes. The physical chemistry of enzyme confinement, methods of immobilization, catalytic activity and advantages of protein confinements are discussed. In the end, we show that immobilized enzymes in the nanospaces of MPS can be applied as viable biocatalysts for chemical and pharmaceutical industries.
• Micro- and nano-patterns created via electrohydrodynamic instabilities
  - Nano Today 4(2):180-192 (2009)
  Intense interests on surfaces with micro- and nano-patterns originated from abundant applications in optics, electronics, tissue engineering, biomedical sensors, etc. Searching for ways to create small patterns in both organic and inorganic materials at reduced operation time and cost is one of the challenges in nanotechnology. This paper reviews recent advances in patterning of thin films by using electrohydrodynamic instabilities, a simple and cost-effective bottom-up method. Challenges and future directions are also discussed from the point of view of both fundamental understanding and technological applications of the pattern formation induced by the electric field.
• Designer self-assembling peptide nanomaterials
  - Nano Today 4(2):193-210 (2009)
  Short peptides that are made of natural amino acids were never seriously considered as useful materials as recent as 16 years ago. However, the discovery of a class of self-assembling peptides that spontaneously undergo self-organization into well-ordered structures resulted in a conceptual change. Since then diverse classes of short peptides have been invented with broad applications including 3D tissue cell culture, reparative and regenerative medicine, tissue engineering, slow drug release, stabilization of membrane proteins to develop nanobiotechnology and molecular devices. Furthermore one of the self-assembling peptides has shown promise not only to slow down prion infection, but also to extend not, vert, similar50% animal life. Molecular design using short peptides as new materials may play increasingly important role in nanoscience, nanotechnology, nanobiotechnology and nanomedicine.