Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Fossilized liquid assembly: Nanomaterials research tool

16.10.2006
From a butterfly's iridescent wing to a gecko's sticky foot, nature derives extraordinary properties from ordinary materials like wax and keratin. Its secret is hierarchical topology: macroscale structures assembled from microscale components of varying sizes.

Borrowing a page from nature's playbook, researchers at the National Institute of Standards and Technology (NIST) have developed a novel platform for the self-assembly of experimental hierarchical surfaces in a fluid. Their work offers diverse industries a new way to generate and measure self-assembly at the nano-scale.

A butterfly's wings shimmer because light plays upon tiny rows of scales, like tiles on a Spanish roof. The gecko sticks to surfaces because its feet are patterned with microscopic hairs, each hair tipped with hundreds of even tinier projections. Beads of water roll off the lotus's leaf because its surface is streaked with microscopic peaks, each with a finer structure, that makes the surface "super hydrophobic." These enhanced properties--other possibilities include super adhesion and low friction--have attracted the attention of design engineers for applications from bioengineered tissues to photonic crystals to submarines that slice through water with minimal drag.

Creating these topologically complex, self-assembled surfaces for study has been a challenge. If the components are mixed on a surface, that substrate affects how they assemble; if mixed in a solvent and dried, the drying process similarly distorts the results. In a recent paper*, the NIST team detailed a much simpler and faster system they dubbed "fossilized liquid assembly" to create experimental models of hierarchical topologies in which the components are allowed to mix and assemble freely in a fluid, and then quickly "frozen" in place for study. The key is the use of solutions of water and a special monomer that polymerizes--links together--when exposed to ultraviolet light. Like an oil-water mixture, the fluid forms liquid interfaces that can be manipulated to create a desired hierarchical structure and then suddenly solidified with a burst of UV light.

Lead researcher and physicist Alamgir Karim estimates that it takes about five minutes to make a sample of self-assembling particles using NIST's approach. Other methods, he notes, not only are more complicated and costly, but also do not allow the structures to form as freely. With the new technique, engineers also will be able to build complex dynamic structures and freeze them into solid form, studying self-assembly under the microscope. "How do you take a snapshot of shampoo in action?" asks physicist Jason Benkoski, first author of the paper. "We can now directly observe these small, mobile, delicate structures."

The researchers also are using the new platform to better understand the fundamental physics behind the formation of hierarchical topology, studying, for example how different forces dominate at different scales of length. Looking ahead, the NIST team plans to build on this study, expanding the technology as a 3D imaging platform.

Mark Bello | EurekAlert!
Further information:
http://www.nist.gov

More articles from Physics and Astronomy:

nachricht Unraveling the nature of 'whistlers' from space in the lab
15.08.2018 | American Institute of Physics

nachricht Early opaque universe linked to galaxy scarcity
15.08.2018 | University of California - Riverside

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

Im Focus: Lining up surprising behaviors of superconductor with one of the world's strongest magnets

Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur

What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

2018 Work Research Conference

25.07.2018 | Event News

 
Latest News

Staying in Shape

16.08.2018 | Life Sciences

Diving robots find Antarctic seas exhale surprising amounts of carbon dioxide in winter

16.08.2018 | Earth Sciences

Protein droplets keep neurons at the ready and immune system in balance

16.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>