By: Sudeep Pasricha, Colorado State University

American mining production increased earlier this decade, as industry sought to reduce its reliance on other countries for key minerals such as coal for energy and rare-earth metals for use in consumer electronics. But mining is dangerous – working underground carries risks of explosions, fires, flooding and dangerous concentrations of poisonous gases.

Mine accidents have killed tens of thousands of mine workers worldwide in just the past decade. Most of these accidents occurred in structurally diverse underground mines with extensive labyrinths of interconnected tunnels. As mining progresses, workers move machinery around, which creates a continually changing environment. This makes search and rescue efforts even more complicated than they might otherwise be.

To address these dangers, U.S. federal regulations require mine operators to monitor levels of methane, carbon monoxide, smoke and oxygen – and to warn miners of possible danger due to air poisoning, flood, fire or explosions. In addition, mining companies must have accident-response plans that include systems with two key capabilities: enabling two-way communications between miners trapped underground and rescuers on the surface, and tracking individual miners so responders can know where they need to dig.

So far, efforts to design systems that are both reliable and resilient when disaster strikes have run into significant roadblocks. My research group’s work is aimed at enhancing commercially available smartphones and wireless network equipment with software and hardware innovations to create a system that is straightforward and relatively simple to operate.

Existing connections

The past decade has seen several efforts to develop monitoring and emergency communication systems, which generally can be classified into three types: through-the-wire, through-the-Earth and through-the-air. Each has different flaws that make them less than ideal options.

Wired systems use coaxial cables or optical fibers to connect monitoring and communications equipment throughout the mine and on the surface. But these are costly and vulnerable to damage from fires and tunnel collapses. Imagine, for example, if a wall collapse cut off a room from its connecting tunnels: Chances are the cable in those tunnels would be damaged too.

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Image: Kim et al.

A team of researchers recently developed a next-generation medical wearable that will make your Fitbit look archaic.

A new study details the development of a small, stretchy sensor that monitors heart rate, blood oxygen levels, and UV radiation exposure – all without batteries or wires.

The patch, which relies on wirelessly transmitted power, uses near-field communication to activate LED lights. Essentially, the energy to power the device is harnessed from wasted energy emitted from surrounding electronics such as smartphones or tablets. The lights then penetrate the skin and reflect back to the sensor, transmitting data to a nearby device. In this application, radio frequencies are used to both transmit communications and provide an energy source.

Without the need for a battery, researchers were able to create an ultra-thin sensor.

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The system consists of a temporary tattoo (left) and a circuit board (right).
Image: UC San Diego

A team of researchers form the University of California, San Diego has developed a flexible, wearable sensor that can accurately measure a person’s blood alcohol level from sweat and transmit the results wirelessly in real time.

The new development provides a continuous, non-invasive alternative to current alcohol level detection methods. Researchers state it also provides a more accurate reading than breathalyzers.

The device consists of a temporary tattoo, which adheres to the skin, induces sweat, and electrochemically detects alcohol levels. The sensor also incorporates a portable, flexible electronic circuit board, which connects to the tattoo and wirelessly communicates the information.

“Lots of accidents on the road are caused by drunk driving,” says Joseph Wang, ECS member and co-author of the study. “This technology provides an accurate, convenient and quick way to monitor alcohol consumption to help prevent people from driving while intoxicated.”

In addition to applications in law enforcement and medicine, Wang believes this device could potentially be integrated with a car’s alcohol ignition interlocks, or used by people to check their own alcohol level before getting behind the wheel.

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CC0 Public Domain

Global estimates report that nearly 600 million people are sickened by a foodborne illness annually, resulting in over 400,000 deaths. In the United States alone, foodborne illnesses such as Salmonella and E. coli result in an overall cost of $77 billion per year.

Researchers from the Washington State University (WSU) are looking to help put an end to the spread of foodborne illnesses with the development of a new and improved biosensor.

We’ve see in in the recent food recalls; harmful pathogens in food are almost always discovered after people have become sick. The work from WSU, led by ECS member Yuehe Lin, focuses on detecting and amplifying the signal of food pathogens, reducing the risk of small (but dangerous) pathogens to go undetected.

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Image: IPC PAS, Grzegorz Krzyzewski

Fungal infections can often be life-threatening, especially for those with weak immune systems. The current standard test to detect the presence of fungi in a person takes at least a dozen hours, with the results sometimes being unreliable. Now, researchers from the Polish Academy of Science have developed a new device that could allow medical practitioners to more quickly and reliably detect fungal infections, allowing for better and faster overall treatment.

The research team, led by ECS member Wlodzimierz Kutner, devised a chemical sensor that can shorten the detection of the fungi from a few days to just a few minutes.

“The most important element of our sensor is a film of polymer selectively recognizing D-arabitol,” Kutner says. “It captures molecules of D-arabitol, a compound indicating the presence of fungi. The measurement takes only a few minutes, and the D-arabitol is detected with a high degree of certainty even in the presence of interfering substances with a similar molecular structure.”

One of the most critical aspects of the treatment of fungal infections is time. The longer these infections go undetected, the more serious they become. This new development will allow for the quick, reliable detection of fungal infections and more successful administration of appropriate fungal therapy.

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Smartphones are amazing little bundles of electrochemistry. From the sensors that pick up your touch and analyze your voice to the battery that is small and powerful enough to provide enough power to run applications on demand – the innovative science behind smartphones has changed the lives of people around the world.

But sometimes those changes are not completely positive. With increased dependence on smartphones, many people now roam the sidewalk with their nose buried in their phones. According to The Wall Street Journal, the number of distracted pedestrians using cellphones is up 124 percent from 2010. Some researchers are even blaming portable electronic gadgets for 10 percent of pedestrian injuries and a half-dozen deaths each year.

In Germany, these distracted pedestrians have been deemed “sombies,” or “smartphone zombies.” And the German government isn’t just looking to throw out a new buzzword, they’re also seeking to solve this issue.

According to reports from The Local, the city of Augsburg recently installed rows of LED lights into the sidewalk that can sense when distracted pedestrians are approaching and give off a bright flash of red to warn them to not mindlessly wander into the street.

“We realized that the normal traffic light isn’t in the line of sight of many pedestrians these days,” said Tobias Harms of the Augsburg city administration in an interview with The Augsburger Allgemeine. “So we decided to have an additional set of lights – the more we have, the more people are likely to notice them.”

HIV and hepatitis C are among the leading causes of worldwide death. According to amfAR, an organization dedicated to eradicating the spread of HIV/AIDS through innovative research, nearly 37 million people are currently living with HIV. Of those 37 million, one third become co-infected with hepatitis C.

The threat of HIV and hepatitis C

The regions hit the hardest by this co-infection tend to be developing parts of the world, such as sub-Saharan Africa and Central and East Asia.

While these developing regions have measures to diagnosis HIV and hepatitis C, the rapid point-of-care tests used are typically unaffordable or unreliable.

An electrochemical solution

A group from McGill University is looking to change that with a recently developed, paper-based electrochemical platform with multiplexing and telemedicine capabilities that may enable low-cost, point-of-care diagnosis for HIV and hepatitis C co-infections within serum samples.

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Artificial limbs have experience tremendous evolution in their long history. Throughout history, we’ve gone from the peg leg of the Dark Ages to technologically advanced modern day prosthesis that mimic the function of a natural limb. However, most prosthesis still lack a sense of touch.

Zhenan Bao, past ECS member and chemical engineer at Stanford University, is at the forefront of the research looking to change that.

(MORE: Read Bao’s past meeting abstracts in the ECS Digital Library for free.)

Recently on NPR’s All Things Considered, Bao described her work in developing a plastic artificial skin that can essentially do all the things organic skin can do, including sensing and self-healing.

The self-healing plastic Bao uses mimics the electrical properties of silicon and contains a nano-scale pressure sensor. The sensor is then connected to electrical circuits that connect to the brain, transmitting the pressure to the brain to analyze as feeling.

Additionally, the skin is set to be powered by polymers that can turn light into electricity.

While there is still much work to be done, Bao and her colleagues believe that this product could help people who have lost their limbs regain their sense of touch.

Glucose monitoring has had a long history with electrochemical science and technology. While ECS Honorary Member Adam Heller’s continuous glucose monitoring system for diabetes management may be the first innovation that comes to mind, there is a new electrochemical bio-sensing tool on the horizon.

(WATCH: ECS Masters – Adam Heller)

Researchers have combined graphene with a tiny amount of gold to enhance the wonder material’s properties and develop a flexible skin patch to monitor blood glucose and automatically administer drugs as needed.

This from Extreme Tech:

[As] cool as a non-invasive blood-glucose monitor is, it’s nearly as revolutionary as what comes next: treatment. The patch is studded with “microneedles” that automatically cap themselves with a plug of tridecanoic acid. When high blood-glucose levels are detected, the patch heats a small heater on the needles which deforms the plug and allows the release of metformin, a common drug for treatment of type 2 diabetes. Cooling naturally restores the plug and stops drug release.

Read the full article.

This development is a huge stepping stone in the transformation of graphene as a laboratory curiosity to a real product. While it has taken a while due to the questions of the new material’s intrinsic properties, researchers believe that graphene-based products could soon be hitting the market.

Measuring the pH level of a solution is usually a relatively simple process. However, that process begins to get more complicated as things get smaller.

Examining changes in acidity or alkalinity at the nanoscale, for example, has been a nearly impossible feat for researchers. Now, a team from the Polish Academy of Sciences in Warsaw, including 11 year ECS member Gunter Wittstock, has developed a novel method of pH measurement at the nanoscale.

The group has developed a nanosensor with the ability to continuously monitor changes in pH levels.

This from the Polish Academy of Sciences in Warsaw:

Used as a scanning electrochemical microscope probe, it allows for the precise measurement of changes in acidity/alkalinity occurring over very small fragments of the surface of a sample immersed in a solution. The spatial resolution here is just 50 nm, and in the future, it can be reduced even further.

Read the full article.

“The ability to monitor changes in the acidity or alkalinity of solutions at the nanoscale, and thus over areas whose dimensions can be counted in billionths of a meter, is an important step toward better understanding of many chemical processes. The most obvious examples here are various kinds of catalytic reactions or pitting corrosion, which begins on very small fragments of a surface,” said Marcin Opallo, lead author in the study.

The team hopes that this new method could lead to monitoring of pH changes taking place in the vicinity of individual chemical molecules.