 |
|
Nano propellers pump with proper chemistry
July 17, 2007The ability to pump liquids at the cellular scale opens up exciting possibilities, such as precisely targeting medicines and regulating flow into and out of cells. But designing this molecular machinery has proven difficult.
Now chemists at the University of Illinois at Chicago have created a theoretical blueprint for assembling a nanoscale propeller with molecule-sized blades.
The work is featured in Research Highlights in the July 12 issue of Nature and was described in the June 28 cover story of Physical Review Letters.
Using classical molecular dynamics simulations, Petr Král, assistant professor of chemistry at UIC, and his laboratory coworkers were able to study realistic conditions in this microscopic environment to learn how the tiny propellers pump liquids.
While previous research has looked at how molecular devices rotate in flowing gases, Král and his group are the first to look at molecular propeller pumping of liquids, notably water and oils.
"We want to see what happens when the propellers get to the scale where it's impossible to reduce the size of the blades any more," said Král.
Král's group found that at the molecular level -- unlike at the macro level -- the chemistry of the propeller's blades and their sensitivity to water play a big role in determining whether the propeller pumps efficiently or just spins with little effect. If the blades have a hydrophobic, or water-repelling nature, they pump a lot of water. But if they are hydrophilic -- water-attracting -- they become clogged with water molecules and pump poorly.
"Pumping rates and efficiencies in the hydrophilic and hydrophobic forms can differ by an order of magnitude, which was not expected," he said.
The UIC researchers found that propeller pumping efficiency in liquids is highly sensitive to the size, shape, chemical or biological composition of the blades.
"In principle, we could even attach some biological molecules to the blades and form a propeller that would work only if other molecules bio-compatible with the blades are in the pumped solution," he said.
The findings present new factors to consider in developing nanoscale liquid-pumping machines, but Král added that such technology probably won't become reality for several years, given the difficult nature of constructing such ultra-small devices.
Král's laboratory studies how biological systems, like tiny flagella that move bacteria, offer clues for building motors, motile systems and other nanoscale devices in a hybrid environment that combines biological and inorganic chemistry.
"The 21st century will be about hybrid biological and artificial nanoscale systems and their mutual co-evolution," Král predicts. "My group alone is working on about a half-dozen such projects. I'm optimistic about such nanoscale developments."
University of Illinois at Chicago
Using classical molecular dynamics simulations, Petr Král, assistant professor of chemistry at UIC, and his laboratory coworkers were able to study realistic conditions in this microscopic environment to learn how the tiny propellers pump liquids.
While previous research has looked at how molecular devices rotate in flowing gases, Král and his group are the first to look at molecular propeller pumping of liquids, notably water and oils.
"We want to see what happens when the propellers get to the scale where it's impossible to reduce the size of the blades any more," said Král.
Král's group found that at the molecular level -- unlike at the macro level -- the chemistry of the propeller's blades and their sensitivity to water play a big role in determining whether the propeller pumps efficiently or just spins with little effect. If the blades have a hydrophobic, or water-repelling nature, they pump a lot of water. But if they are hydrophilic -- water-attracting -- they become clogged with water molecules and pump poorly.
"Pumping rates and efficiencies in the hydrophilic and hydrophobic forms can differ by an order of magnitude, which was not expected," he said.
The UIC researchers found that propeller pumping efficiency in liquids is highly sensitive to the size, shape, chemical or biological composition of the blades.
"In principle, we could even attach some biological molecules to the blades and form a propeller that would work only if other molecules bio-compatible with the blades are in the pumped solution," he said.
The findings present new factors to consider in developing nanoscale liquid-pumping machines, but Král added that such technology probably won't become reality for several years, given the difficult nature of constructing such ultra-small devices.
Král's laboratory studies how biological systems, like tiny flagella that move bacteria, offer clues for building motors, motile systems and other nanoscale devices in a hybrid environment that combines biological and inorganic chemistry.
"The 21st century will be about hybrid biological and artificial nanoscale systems and their mutual co-evolution," Král predicts. "My group alone is working on about a half-dozen such projects. I'm optimistic about such nanoscale developments."
University of Illinois at Chicago
Nanoscale Current Events and Nanoscale News RSSSmall optical force can budge nanoscale objects
With a bit of leverage, Cornell researchers have used a very tiny beam of light with as little as 1 milliwatt of power to move a silicon structure up to 12 nanometers. That's enough to completely switch the optical properties of the structure from opaque to transparent, they reported.
Small nanoparticles bring big improvement to medical imaging
If you're watching the complex processes in a living cell, it is easy to miss something important-especially if you are watching changes that take a long time to unfold and require high-spatial-resolution imaging.
Pushing light beyond its known limits
Scientists at the University of Adelaide have made a breakthrough that could change the world's thinking on what light is capable of.
Nanotech in Space: Rensselaer Experiment To Weather the Trials of Orbit
Novel nanomaterials developed at Rensselaer Polytechnic Institute are scheduled to blast off into orbit on November 16 aboard Space Shuttle Atlantis.
Caltech scientists develop DNA origami nanoscale breadboards for carbon nanotube circuits
In work that someday may lead to the development of novel types of nanoscale electronic devices, an interdisciplinary team of researchers at the California Institute of Technology (Caltech) has combined DNA's talent for self-assembly with the remarkable electronic properties of carbon nanotubes, thereby suggesting a solution to the long-standing problem of organizing carbon nanotubes into nanoscale electronic circuits.
Engineers image nanostructure of a solid acid catalyst and boost its catalytic activity
The catalytic processes that facilitate the production of many chemicals and fuels could become much more environmentally friendly thanks to a breakthrough achieved by researchers from Lehigh and Rice Universities.
Findings show nanomedicine promising for treating spinal cord injuries
Researchers at Purdue University have discovered a new approach for repairing damaged nerve fibers in spinal cord injuries using nano-spheres that could be injected into the blood shortly after an accident.
Magnetic nanoparticles to simultaneously diagnose, monitor and treat
Whether it's magnetic nanoparticles (mNPs) giving an army of 'therapeutically armed' white blood cells direction to invade a deadly tumour's territory, or the use of mNPs to target specific nerve channels and induce nerve-led behaviour (such as the life-dependant thumping of our hearts), mNPs have come a long way in the past decade.
Breakthrough in industrial-scale nanotube processing
Rice University scientists today unveiled a method for the industrial-scale processing of pure carbon-nanotube fibers that could lead to revolutionary advances in materials science, power distribution and nanoelectronics.
LANL Roadrunner simulates nanoscale material failure
Very tiny wires, called nanowires, made from such metals as silver and gold, may play a crucial role as electrical or mechanical switches in the development of future-generation ultrasmall nanodevices.
More Nanoscale Current Events and Nanoscale News Articles
 |
Nanoscale: Visualizing an Invisible World by Kenneth S. Deffeyes (Author), Stephen E. Deffeyes (Author) The world is made up of structures too small to see with the naked eye, too small to see even with an electron microscope. Einstein established the reality of atoms and molecules in the early 1900s. How can we see a world measured in fractions of nanometers? (Most atoms are less than one nanometer, less than one-billionth of a meter, in diameter.) This beautiful and fascinating book gives us a tour of the invisible nanoscale world. It offers many vivid color illustrations of atomic structures, each accompanied by a short, engagingly written essay. The structures advance from the simple (air, ice) to the complex (supercapacitor, rare earth magnet). Each subject was chosen not in search of comprehensiveness but because it illustrates how atomic structure creates a property (such as... |
 |
SpillKlenz by NanoScale Corporation Odor eliminating liquid absorbent facilitates immediate clean-up of liquids by quickly absorbing spills and neutralizing the accompanying odors. |
 |
SpillKlenz Travel Kit by NanoScale Corporation Odor eliminating liquid absorbent kit facilitates immediate clean-up of liquids by quickly absorbing spills and neutralizing the accompanying odors. The kit provides spill control and containment in confined spaces where clean-up is inconvenient. Kit includes 2 revolutionary odor neutralizing sorbent packets, 2 sanitizing wipes, 2 disposal bags, 1 scoop and scraper, and 1 pair of non-latex gloves. |
 |
OdorKlenz Laundry, Medium by NanoScale Corporation OdorKlenz Laundry is an odor elimination laundry additive which eliminates tough odors regular detergents leave behind. |
 |
No Small Matter: Science on the Nanoscale by Felice C. Frankel (Author), George M. Whitesides (Author) A small revolution is remaking the world. The only problem is, we can’t see it. This book uses dazzling images and evocative descriptions to reveal the virtually invisible realities and possibilities of nanoscience. An introduction to the science and technology of small things, No Small Matter explains science on the nanoscale. Authors Felice C. Frankel and George M. Whitesides offer an overview of recent scientific advances that have given us our ever-shrinking microtechnology—for instance, an information processor connected by wires only 1,000 atoms wide. They describe the new methods used to study nanostructures, suggest ways of understanding their often bizarre behavior, and outline their uses in technology. This book explains the various means of making... |
 |
Nanoscale Geordie Haley (Primary Contributor) |
 |
Electrical Transport in Nanoscale Systems by Massimiliano Di Ventra (Author) This graduate textbook provides an in-depth description of the transport phenomena relevant to systems of nanoscale dimensions. The different theoretical approaches are critically discussed, with emphasis on their basic assumptions and approximations. The book also covers information content in the measurement of currents, the role of initial conditions in establishing a steady state, and the modern use of density-functional theory. Topics are introduced by simple physical arguments, with particular attention to the non-equilibrium statistical nature of electrical conduction, and followed by a detailed formal derivation. This textbook is ideal for graduate students in physics, chemistry, and electrical engineering. |
 |
Microscale and Nanoscale Heat Transfer: Fundamentals and Engineering Applications by Choondal B. Sobhan (Author), G. P. "Bud" Peterson (Author) Through analyses, experimental results, and worked-out numerical examples, Microscale and Nanoscale Heat Transfer: Fundamentals and Engineering Applications explores the methods and observations of thermophysical phenomena in size-affected domains. Compiling the most relevant findings from the literature, along with results from their own research activities, the authors provide a useful treatise on the principal concepts and practical design engineering aspects of heat transfer. The book discusses in detail various modern engineering applications, such as microchannel heat sinks, micro heat exchangers, and micro heat pipes. It covers methods that range from discrete computation to optical measurement techniques for microscale applications. The authors also present the fundamentals... |
 |
Nanoscale: Issues and Perspectives for the Nano Century by Nigel Cameron (Editor), M. Ellen Mitchell (Editor) An authoritative examination of the present and potential impact of nanoscale science and technology on modern life Because truly transformative technologies have far-reaching consequences, they always generate controversy. Establishing an effective process for identifying and understanding the broad implications of nanotechnology will advance its acceptance and success, impact the decisions of policymakers and regulatory agencies, and facilitate the development of judicious policy approaches to new technology options. Nanoscale: Issues and Perspectives for the Nano Century addresses the emerging ethical, legal, policy, business, and social issues. A compilation of provocative treatises, this reference: Covers an area of increasing research and funding ... |
 |
Fabrication Engineering at the Micro and Nanoscale (The Oxford Series in Electrical and Computer Engineering) by Stephen A. Campbell (Author) Designed for advanced undergraduate or first-year graduate courses in semiconductor or microelectronic fabrication, the third edition of Fabrication Engineering at the Micro and Nanoscale provides a thorough and accessible introduction to all fields of micro and nano fabrication. Completely revised and updated, the text covers the entire basic unit processes used to fabricate integrated circuits and other devices. It includes more worked examples, illustrations, and expands coverage of the frontiers of fabrication processes. The physics and chemistry of each process are introduced along with descriptions of the equipment used to carry out the processes. The text uses a popular commercial process simulation suite--the Silvaco AthenaRG set of codes--to provide meaningful examples of... |
| © 2009 BrightSurf.com |