Category Chemistry/Nanotechnology

Secretion in droplet-embedded gel permits self-repairing behavior. Three-dimensional confocal fluorescence images show damaged gel (top) after 0.5 hours and the self-repaired gel after 72 hours (bottom). Credit: Image courtesy of Joanna Aizenberg

Inspired by healing wounds in skin, a new approach protects and heals surfaces using a fluid secretion process. In response to damage, dispersed liquid-storage droplets are controllably secreted. The stored liquid replenishes the surface and completes the repair of the polymer in seconds to hours.

The fluid secretion approach to repair the material has also been demonstrated in fibers and microbeads...

This is a gold nanoparticle, brought into contact to a DNA nanostructure, sticks to chemical patches. Scientists then dissolve the assembly, separating the DNA nanostructure into its component strands and leaving behind the DNA imprint on the gold nanoparticle. Credit: Thomas Edwardson

New technique could facilitate use of gold nanoparticles in electronic, medical applications. Gold nanoparticles have unusual optical, electronic and chemical properties, which scientists are seeking to put to use in a range of new technologies, from nanoelectronics to cancer treatments.

Some of the most interesting properties of nanoparticles emerge when they are brought close together – either in clusters of just a few particles or in crystals made up of millions of them...

A schematic of the new laser system. Credit: Image courtesy of Northwestern University

High power and rapid tuning for the detection of hazardous chemicals. From their use in telecommunication to detecting hazardous chemicals, lasers play a major role in our everyday lives. They keep us connected, keep us safe, and allow us to explore the dark corners of the universe. Now a Northwestern University team has made this ever-important tool even simpler and more versatile by integrating a mid-infrared tunable laser with an on-chip amplifier. This breakthrough allows adjustable wavelength output, modulators, and amplifiers to be held inside a single package.

With this architecture, the laser has demonstrated an order-of-magnitude more output power than its predecessors, and the tuning range has ...

Coffee flour. Credit: Image courtesy of Brandeis University

Biophysicist Perlman is developing the flour milled from parbaked beans both as a food ingredient and a nutritional supplement. “It’s a world of difference” from the traditional coffee bean, Perlman says. Research has shown that drinking coffee is good for you. A recent Harvard study found that people who drank three to five cups a day had a 15% lower chance of prematurely dying than non-drinkers.

Nobody knows for certain what causes coffee to be salutary, but one leading explanation involves a natural chemical compound called chlorogenic acid (CGA). An antioxidant, CGA is thought to be beneficial in modulating sugar metabolism, controlling BP and possibly treating heart disease and cancer.

Unfortunately, when coffee is roasted th...