Category Chemistry/Nanotechnology

A photograph shows regenerated helical silk fibers colored by Rhodamine dyes, under UV light. Credit: Courtesy of the researchers

Reconstituted silk can be several times stronger than the natural fiber and made in different forms. When it comes to concocting the complex mix of molecules that makes up fibers of natural silk, nature beats human engineering hands down. Despite efforts to synthesize the material, artificial varieties still cannot match the natural fiber’s strength. But by starting with silk produced by silkworms, breaking it down chemically, and then reassembling it, engineers have found they can make a material that is more than twice as stiff as its natural counterpart and can be shaped into complex structures such as meshes and lattices...

A new pencil-like wireless spectrometer can be used with a smartphone to collect 3-D spectral images of the body and other objects. This design could make the device useful for point-of-care diagnostics. Credit: Dan Wang, Beijing University of Chemical Technology

Easy-to-use spectrometer less than $300, holds promise for remote medical diagnostics. A new smartphone-compatible device that is held like a pencil could make it practical to acquire spectral images of everyday objects and may eventually be used for point-of-care medical diagnosis in remote locations. Spectral images, which contain more color information than is obtainable with a typical camera, reveal characteristics of tissue and other biological samples that can’t be seen by the naked eye...

Diamidophosphate (DAP)

Chemists at The Scripps Research Institute (TSRI) have found a compound that may have been a crucial factor in the origins of life on Earth. Origins-of-life researchers have hypothesized that a chemical reaction called phosphorylation may have been crucial for the assembly of three key ingredients in early life forms: short strands of nucleotides to store genetic information, short chains of amino acids (peptides) to do the main work of cells, and lipids to form encapsulating structures such as cell walls. Yet, no one has ever found a phosphorylating agent that was plausibly present on early Earth and could have produced these three classes of molecules side-by-side under the same realistic conditions.

TSRI chemists have now identified just such a compound: diamidoph...

The Burton lab studies tiny, plastic particles as a model for more complex systems. The particles are suspended in a vacuum chamber filled with a plasma — ionized argon gas. Credit: Justin Burton, Emory University

Complex behavior emerges from a simple system in a fixed environment. Physicists at Emory University have shown how a system of lifeless particles can become “life-like” by collectively switching back and forth between crystalline and fluid states – even when the environment remains stable. “We’ve discovered perhaps the simplest physical system that can consistently keep changing behavior over time in a fixed environment,” says Justin Burton, Emory assistant professor of physics. “In fact, the system is so simple we never expected to see such a complex property emerge from it.”

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