American Chemical Society


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American Chemical Society, ACS is a congressionally chartered independent membership organization which represents professionals at all degree levels and in all fields of chemistry and sciences that involve chemistry.Learn more about ACS

Most Recent Articles by American Chemical Society:

Sorghum: health food, sweetener and now, clothing dye

May 24, 2017 — American Chemical Society

Sorghum has long been a staple food in many parts of the world, but in the U.S., it’s best known as a sweetener and livestock feed. As demand for the grain soars, so does the amount of waste husks. To reduce this waste, scientists report in the journal ACS Sustainable Chemistry & Engineering a new use for it: a wool dye that can add ultraviolet protection and fluorescence properties to clothing.

Sorghum, which looks like pearl couscous, is a hardy, drought-tolerant crop that is gaining popularity as a health food, livestock feed and source of bioethanol. Additionally, scientists are working on transforming the crop’s waste for a range of applications, including food coloring and waste water purification. Building further on the colorant possibilities, Yiqi Yang, Xiuliang Hou and colleagues wanted to see if they could develop a practical clothing dye out of sorghum husks.

Paper test strip could help heart failure patients monitor their condition at home

May 24, 2017 — American Chemical Society

Contrary to the condition’s name, heart failure doesn’t mean the heart has stopped pumping — it’s just not working at full strength. It can often be managed with medications and lifestyle changes, but its progression needs to be monitored closely. Now scientists have developed a new test strip that could potentially allow patients to do this at home for the first time. Their study appears in the journal ACS Nano.

Should you pee on a jellyfish sting? (video)

May 23, 2017 — American Chemical Society

WASHINGTON — Sure, jellyfish look pretty serene, but we all know the evils that come from a run-in with those tentacles. You’ve probably heard the rumor that peeing on a jellyfish sting can make the pain go away, but does this icky old wives tale stand up to science? Filmed at San Francisco’s Aquarium of the Bay, the latest Reactions episode explains the fearsome chemistry of jellyfish stings, and debunks this age-old beach myth.

The impact of the rise in new drug rejections

May 21, 2017 — American Chemical Society

The number of new drug applications rejected by the U.S. Food and Drug Administration has been on the rise. The cover story of Chemical & Engineering News (C&EN), the weekly newsmagazine of the American Chemical Society, explores why this is happening and what it means for patients.

Ann Thayer, a senior correspondent for C&EN, notes that in 2016, the FDA turned down 14 applications for novel drugs, more than the agency has rejected in recent years. Concurrent with this increase is a growing reliance on outside manufacturers. While outsourcing gives drug companies access to specialized manufacturing plants, it also opens them up to any problems those external firms might have. Often, drug rejections are due to these companies’ failure to comply with good manufacturing practices.

Many drug companies and manufacturers eventually resolve the glitches and get their drugs approved. But the process can take a few months to a few years, which can leave patients with fewer treatment options while the snags get addressed. To help reduce delays, the FDA is providing guidance to drug companies for drawing up manufacturing-quality agreements with outside firms to help fix these problems before they have a chance to hold up applications.

Read the story here.

Conductive paper could enable future flexible electronics

May 21, 2017 — American Chemical Society

Roll-up computer screens and other flexible electronics are getting closer to reality as scientists improve upon a growing number of components that can bend and stretch. One team now reports in the journal ACS Applied Materials & Interfaces another development that can contribute to this evolution: a low-cost conductive paper that would be easy to manufacture on a large scale.

Current flexible electronic prototypes are commonly built using polymer thin films. But the cost of these films becomes a factor when they are scaled up. To address this issue, scientists have turned to paper, which is renewable, biodegradable and a fraction of the cost of polymer thin films. The downside of paper is that it’s not conductive, and efforts so far to infuse it with this property have been hindered by scalability and expense. Bin Su, Junfei Tian and colleagues wanted to come up with a new approach.

Using a conventional roller process that’s easy to scale up, the researchers coated paper with soft ionic gels to make it conductive. They sandwiched an emissive film between two layers of the ionic gel paper. When they applied a voltage, the device glowed blue, indicating that electricity was being conducted. It also showed electrical durability, withstanding more than 5,000 cycles of bending and unbending with negligible changes in performance and lasting for more than two months. The researchers say their conductive paper, which costs about $1.30 per square meter and could be fabricated at a rate of 30 meters per minute, could become an integral part of future flexible electronics.

Ionic Gel Paper with Long-Term Bendable Electrical Robustness for Use in Flexible Electroluminescent Devices

Why a crackly crust is essential to a baguette’s aroma and taste

May 21, 2017 — American Chemical Society

An authentic French baguette is one of those key staples that foodies hunt for. Now scientists have gained new insight into why a crisp crust is a must for this quintessential bread. They report their findings on how crumb and crust structure affect aroma — and therefore, perceived taste — in ACS’ Journal of Agricultural and Food Chemistry.

The smell of baked bread that’s fresh out of the oven is mouth-watering, but the effect of aroma doesn’t stop there. Chewing food also releases molecules that waft in our mouths, interacts with olfactory receptors and influence how we perceive what we’re eating. Understanding this dynamic could help food scientists improve the taste of products. Taking the baguette as an example to explore this possibility, Anne Saint-Eve and colleagues wanted to see how its texture would affect its aroma when chewed.

The researchers had three study participants eat samples of nine baguettes, each with different crumb and crust densities, water content and elasticity. An analysis of volatile organic compounds that are exhaled through the “nose spaces” of the participants along with their chewing activity showed that firm bread and brittle crust led to more chewing and a greater rate of release of aroma molecules. The findings could help food scientists create new bread types better tailored to meet consumers’ expectations, the researchers say.

Effect of Bread Crumb and Crust Structure on the in Vivo Release of Volatiles and the Dynamics of Aroma Perception

‘Heroes of Chemistry’ improve people’s lives through the transforming power of chemistry

May 9, 2017 — American Chemical Society

WASHINGTON — Scientists who developed products that have led to significant advancements in human health, technology, the food supply, and the environment, will be inducted into a scientific “Hall of Fame” later this summer, becoming the newest Heroes of Chemistry, an honor bestowed by the American Chemical Society (ACS), the world’s largest scientific society.

Turning chicken poop and weeds into biofuel

May 5, 2017 — American Chemical Society

Chicken is a favorite, inexpensive meat across the globe. But the bird’s popularity results in a lot of waste that can pollute soil and water. One strategy for dealing with poultry poop is to turn it into biofuel, and now scientists have developed a way to do this by mixing the waste with another environmental scourge, an invasive weed that is affecting agriculture in Africa.

Poultry sludge is sometimes turned into fertilizer, but recent trends in industrialized chicken farming have led to an increase in waste mismanagement and negative environmental impacts, according to the United Nations Food and Agriculture Organization. Droppings can contain nutrients, hormones, antibiotics and heavy metals and can wash into the soil and surface water. To deal with this problem, scientists have been working on ways to convert the waste into fuel. But alone, poultry droppings don’t transform well into biogas, so it’s mixed with plant materials such as switch grass. Samuel O. Dahunsi, Solomon U. Oranusi and colleagues wanted to see if they could combine the chicken waste with Tithonia diversifolia (Mexican sunflower), which was introduced to Africa as an ornamental plant decades ago and has become a major weed threatening agricultural production on the continent.

The researchers developed a process to pre-treat chicken droppings, and then have anaerobic microbes digest the waste and Mexican sunflowers together. Eight kilograms of poultry waste and sunflowers produced more than 3 kg of biogas — more than enough fuel to drive the reaction and have some leftover for other uses such as powering a generator. Also, the researchers say that the residual solids from the process could be applied as fertilizer or soil conditioner.

Bioconversion of Tithonia diversifolia (Mexican Sunflower) and Poultry Droppings for Energy Generation: Optimization, Mass and Energy Balances, and Economic Benefits

‘Lab-on-a-glove’ could bring nerve-agent detection to a wearer’s fingertips (video)

May 5, 2017 — American Chemical Society

There’s a reason why farmers wear protective gear when applying organophosphate pesticides. The substances are very effective at getting rid of unwanted bugs, but they can also make people sick. Related compounds — organophosphate nerve agents — can be used as deadly weapons. Now researchers have developed a fast way to detect the presence of such compounds in the field using a disposable “lab-on-a-glove.” The report on the glove appears in the journal ACS Sensors.

Organophosphate nerve agents, including sarin and VX, are highly toxic and can prevent the nervous system from working properly. Organophosphate pesticides are far less potent but work in a similar way and can cause illness in people who are exposed to them, according to the U.S. Centers for Disease Control and Prevention. Detecting either type of these sets of compounds accurately and quickly could help improve both defense and food security measures. So, Joseph Wang and colleagues set out to develop a wearable sensor that could meet the requirements of field detection.

The chemistry of whiskey

May 2, 2017 — American Chemical Society

WASHINGTON — Derby Day is around the corner, and with it comes big hats, horses with funny names, and bourbon. The latest episode of Reactions celebrates the chemical process of distillation that makes bourbon and other whiskey varieties possible. Since water and ethanol, along with tasty flavors, have different boiling points, they can be separated by carefully heating the mash that starts off every whiskey. Each distillery carefully protects their still design, engineered to create their signature liquor. The strongest flavors take aging, but might some innovative whiskey makers find a way to hack maturation time? There’s a barrel-full of chemistry in this video about whiskey.

Toward a safer permanent hair dye that mimics melanin

Apr 30, 2017 — American Chemical Society

Coloring hair has become a common practice, particularly for people who want to hide their graying locks. But an ingredient in many of today’s commercial hair dyes has been linked to allergic reactions and skin irritation. Now scientists have developed a potentially safer alternative by mimicking the hair’s natural color molecule: melanin. Their report appears in the journal ACS Biomaterials Science & Engineering.

The permanent hair dye ingredient p-phenylenediamine (PPD) has been associated, although rarely, with allergic reactions including facial swelling and rashes. Coloring hair with natural melanin would be an intuitive alternative to PPD. But previous research has found that the pigment molecules clump together, forming rods and spheres too large to penetrate into the hair shaft to create lasting color. Jong-Rok Jeon and colleagues wanted to build on the idea of using melanin but with a molecule that mimics the real thing.

The researchers turned to polydopamine, a black substance that is structurally similar to melanin and has been explored for use in a variety of biomedical applications. Polydopamine with iron ions transformed gray hairs into black and lasted through three wash cycles. Lighter shades could also be achieved with polydopamine by pairing it with copper and aluminum ions. And toxicity tests showed that mice treated with the colorant didn’t have noticeable side effects, while those that received a PPD-based dye developed bald spots.

Read More…”Metal-Chelation-Assisted Deposition of Polydopamine on Human Hair: A Ready-to-Use Eumelanin-Based Hair Dyeing Methodology

Art of paper-cutting inspires self-charging paper device

Apr 30, 2017 — American Chemical Society

Despite the many advances in portable electronic devices, one thing remains constant: the need to plug them into a wall socket to recharge. Now researchers, reporting in the journal ACS Nano, have developed a light-weight, paper-based device inspired by the Chinese and Japanese arts of paper-cutting that can harvest and store energy from body movements.

Portable electronic devices, such as watches, hearing aids and heart monitors, often require only a little energy. They usually get that power from conventional rechargeable batteries. But Zhong Lin Wang, Chenguo Hu and colleagues wanted to see if they could untether our small energy needs from the wall socket by harvesting energy from a user’s body movements. Wang and others have been working on this approach in recent years, creating triboelectric nanogenerators (TENGs) that can harness the mechanical energy all around us, such as that created by our footsteps, and then use it to power portable electronics. But most TENG devices take several hours to charge small electronics, such as a sensor, and they’re made of acrylic, which is heavy.

So the researchers turned to an ultra-light, rhombic paper-cut design a few inches long and covered it with different materials to turn it into a power unit. The four outer sides, made of gold- and graphite-coated sand paper, comprised the device’s energy-storing supercapacitor element. The inner surfaces, made of paper and coated in gold and a fluorinated ethylene propylene film, comprised the TENG energy harvester. Pressing and releasing it over just a few minutes charged the device to 1 volt, which was enough to power a remote control, temperature sensor or a watch.


Read more…”Ultralight Cut-Paper-Based Self-Charging Power Unit for Self-Powered Portable Electronic and Medical Systems

Longer-lasting pain relief with Metal-organic frameworks

Apr 27, 2017 — American Chemical Society

To treat headaches, back pain or fever, most of us have reached for ibuprofen at one point or another. But we often have to take doses every four to six hours if the pain warrants it. Now scientists are working on a way to package the commonly used drug so it can last longer. Their approach, reported in ACS’ journal Molecular Pharmaceutics, could also be used to deliver other drugs orally that currently can only be taken intravenously.

Recently, scientists have been studying compounds called metal-organic frameworks (MOFs), which are made of metal ions linked to organic ligands, for drug delivery. Active ingredients can be packed inside MOFs, which are porous, and some of them have additional traits such as water solubility that make them good candidates for drug couriers. But few studies have so far investigated whether such MOFs could be used in oral formulations. J. Fraser Stoddart and colleagues wanted to test promising MOFs using ibuprofen as a model drug.

The researchers loaded therapeutically relevant concentrations of ibuprofen into easily prepared, biocompatible MOFs with cyclodextrin and alkali metal cations. Testing in mice showed that the compounds reached the blood stream quickly in about 10 to 20 minutes and lasted twice as long as ibuprofen salts, which are the active ingredient in commercial liquid gel formulations. The researchers say the promising findings suggest that these compounds could take the next step toward commercial development for delivering ibuprofen and potentially other drugs.

Read: Encapsulation of Ibuprofen in CD-MOF and Related Bioavailability Studies

Synthetic two-sided gecko’s foot could enable underwater robotics

Apr 27, 2017 — American Chemical Society

Geckos are well known for effortlessly scrambling up walls and upside down across ceilings. Even in slippery rain forests, the lizards maintain their grip. Now scientists have created a double-sided adhesive that copies this reversible ability to stick and unstick to surfaces even in wet conditions. They say their development, reported in ACS’ Journal of Physical Chemistry C, could be useful in underwater robotics, sensors and other bionic devices.