Nanotechnology

Enhanced Antisense Drug Delivery and Expression

Antisense refers to therapies that block cancer genes from producing proteins that promote cancer. But development of these drugs is difficult since the nanoscale pieces of DNA or RNA that comprise these drugs have some difficulty penetrating cancer cells. Gold nanoparticles seem to aid in delivery of DNA molecules safely into cancer cells. Read the news here.

Superlens Created

Light microscopy, but not electron microscopy, can be used to image living tissues. But  400 nanometers is the shortest wavelength that allows imaging without damage to the tissue itself. Evanescent waves allow researchers to get around this limitation. Researchers have made a lens out of a 35-nanometer-thick film of silver, which they used with a light source of identical frequency (the same resonant frequency of the lens's electrons). The light shone through the word "NANO," inscribed in letters with a 40-nanometer line width on a piece of chromium through ion beam lithography. Upon exposure to the light, the silver electrons resonated with the evanescent waves, providing enhanced excitement. A light-sensitive material was also used to capture the lens directed waves. This work could allows researchers to view biological processes in real time as they naturally occur, something not possible using present technologies. To learn more read here or see Science, Vol 308, Issue 5721, 534-537 , 22 April 2005.

Nano Valve - A Switchable Molecular Trap

UCLA chemists have created a nano valve that can be opened and closed at will to trap and release molecules. The discovery was federally funded by the National Science Foundation. "This paper demonstrates unequivocally that the machine works," said Jeffrey I. Zink, a UCLA professor of chemistry and biochemistry, a member of the California NanoSystems Institute at UCLA, and a member of the research team. "With the nano valve, we can trap and release molecules on demand. We are able to control molecules at the nano scale. "A nano valve potentially could be used as a drug delivery system," Zink said. "The valve is like a mechanical system that we can control like a water faucet," said UCLA graduate student Thoi Nguyen, lead author on the paper. "Trapping the molecule inside and shutting the valve tightly was a challenge." See more here or read the manuscript at PNAS.

Nanobiotechnologist Creates Self-Assembling Nano-Electronics Exhibiting Complex Geometric Behavior

Mutidisciplinary scientists at the University of Wisconsin-Madison have developed a process for mixing polymers which results in self-assembly into nanoscale patterns that can turn corners and display other complex geometries. Reported in the journal Science, chemical and biological engineer Paul Nealey describes how previous research demonstrated a lithographc technique for creating patterns in the chemistry of polymeric materials used as templates for nanomanufacturing. In their previous report, Nealey deposited a film of block copolymers on a chemically patterned surface such that the molecules arranged themselves to replicate the underlying pattern without imperfections. Now he goes further. Although the previous technique works well for creating templates that are neatly ordered in periodic arrays, one of the challenges of nanofabrication is integrating these self-assembling materials, which naturally form periodic structures, into existing manufacturing strategies. View his report.

Piva Reports Findings on Alterations to Single-molecule Conductivity by a Charged Surface Atom

Paul G. Piva and colleagues report that although electrical transport through molecules has been much investigated and research has shown that single-molecule electronic effects have been observed, transport is sensitive to structural variations on the atomic scale. Understanding how the structural features affect such properties is of importance. His group has demonstrated that the electrostatic field emanating from a fixed point charge regulates the conductivity of nearby substrate-bound molecules. These results show that molecular conduction is shifted by altering the charge state of a silicon surface atom, or by varying the spatial relationship between the molecule and that charged center. Read their article, appearing in Nature, here.

Nanonews and Activities through May

Nanonews! including the President's Advisory Council of Advisors on Science and Technology Report on the National Nanotechnology Initiative, the UK citizen's NanoJury, a Science journal article on an American Chemical Society report on nanofibers seeding blood vessels, Nanotechnology Law and Business Journal's article on nano weapons of mass destruction, and Rutgers University Professor Stephen Danforth on student involvement in nanotechnology and the future. Also highlights from the Chemical and Engineering News cover story on nanotechnology investing. To listen click here. Subscribe here.

Europe's Nanosafe2 Program

BASF has released news that it will participate in the Nanosafe2 program to better understand risks associated with the use of nanoparticles. Nanosafe2 establishes processes to detect, track and characterize nanoparticles by looking at the entire lifecycle of nanoparticles, from their production and storage through to transport and use in a finished product. “As part of the EU project, we will be carrying out studies to increase our understanding of the possible health risks associated with the inhalation of nanoparticles,” explained Dr. Edgar Leibold from BASF’s Toxicology department. More about Nanosafe2.

Sandia Porphyrin Nanotubes and Broader R&D Goals

Sandia National Laboratories is developing alternatives to carbon nanotubes (since some suggest the nanotube chemical properties are unique and perhaps unpredictable). “The broad objective of the research is to design and fabricate new types of nanoscale devices,” says John Shelnutt, Sandia research team leader. Shelnutt’s team uses porphyrins, which are light-absorbing molecules related to chlorophyll, the active part of photosynthetic proteins and light-harvesting nanostructures (chlorosomal rods). Porphyrin nanotubes are made entirely of oppositely charged porphyrin molecules that self-assemble in water at room temperature. These differ from the more well-known carbon nanotubes, which are formed at high temperatures and have covalent bonds between carbon atoms. Listen to an mp3 containing an introduction to nanotechnology and outlining Sandia’s broader nanotechnology program goals and initiatives here, or subscribe here.

Nanotechnology on the Frontline: Interview with Professor N. Seeman, Creator of the Nano Biped & Nano Translation Device

A framework discussion with Dr. Nadrian Seeman, Founding President of the International Society for Nanoscale Science and Engineering and Professor of Chemistry at New York University, about the potential of the nanotechnology revolution. He discusses his work with the fundamental unit of life, DNA, and the use of DNA to create various model nanotechnology devices. A recent article published in Science magazine.  Listen and/or subscribe to the NANO podcast.