Tag Archives: sensor

Glove sensors and toxic substances

Gloves that change colour as a signal you’re handling toxic substances have been developed by a research team at  the Fraunhofer Institute according to a May 2, 2013 Fraunhofer Research Institution for Modular Solid State Technologies EMFT news release (also on EurekAlert as a re-issued June 7, 2013 news release),

Employees in chemical production, the semiconductor industry or in laboratories are frequently exposed to harmful substances. The problem: Many of these aggressive substances are imperceptible to human senses, which makes handling them so risky. That’s why there is a broad range of solutions that employers can use to protect their staff from hazardous substances – from highly sensitive measuring equipment to heat imaging cameras. Soon, this spectrum will be enhanced by one more clever solution that is easy to handle, and that dispenses with a power supply. Researchers at the Fraunhofer Research Institution for Modular Solid State Technologies EMFT in Regensburg have engineered a glove that recognizes if toxic substances are present in the surrounding air.

Here’s an image of the glove,

The sensor glove turns blue in the presence of hazardous substances. (© Fraunhofer EMFT)

The sensor glove turns blue in the presence of hazardous substances. (© Fraunhofer EMFT)

The news release provides more details,

The protective glove is equipped with custom-made sensor materials and indicates the presence of toxic substances by changing colors. In this regard, the scientists adapted the materials to the corresponding analytes, and thus, the application. The color change – from colorless (no toxic substance) to blue (toxic substance detected), for example – warns the employee immediately. …

….

The warning signal is triggered by an indicator dye integrated into the glove that reacts to the presence of analytes, in this case, the toxic substances. The experts at EMFT used a variety of techniques in order to furnish textiles with sensor-activated dyes. The sensor-activated dyes are applied to the clothing with the customary dye and print process, for example, by affixing them in an immersion bath. Previously, the researchers used targeted chemical modification to adapt the color molecules to the fiber properties of the respective textile. Alternatively, the textiles can also be coated with sensor particles that are furnished with sensor dyes. For this purpose, the scientists integrated the dye molecules either into commercial pigments or they built them up on an entirely synthetic basis. The pigments are then manufactured according to the customary textile finishing process, for instance, the sensor particles are also suitable for silkscreening. “Which version we opt for depends on the requirements of the planned application,” says Trupp [Dr. Sabine Trupp, head of the Fraunhofer EMFT Sensor Materials group].

The challenge lies foremost in the tailored development of sensor dyes. “The dye molecule must detect a specific analyte in a targeted manner – only then will a chemical reaction occur. Moreover, the dye must adhere securely; it cannot disappear due to washing. We aim for the customer’s preferences in the color selection as well. All of these aspects must be kept in mind when developing the molecule and pigment properties,” explains Trupp.

The technology could be extended to do more and could be adapted for other applications (from the news release),

The expert already has new ideas about how the solution could be developed further. For example, a miniaturized sensor module, integrated into textiles, could record toxic substances, store the measurement data and even transmit them to a main unit. This way, you could document how frequently an individual within a hazardous environment was exposed to poisonous concentrations over a longer period of time.

The researchers also envision other potential applications in the foodstuffs industry: In the future, color indicator systems integrated into foils or bottle closures are intended to make the quality status of the packaged foods visible. Because the sell-by date does not represent a guarantee of any kind. Foodstuffs may often spoil prematurely – unnoticed by the consumer – due to a packaging error, or in the warehousing, or due to disruptions in the refrigeration chain. Oil-based and fat-containing products are specifically prone to this, as are meats, fish and ready meals.

The notion that food packaging could be designed to include sensors that alert consumers and retailers about product spoilage is not new and was mentioned recently and briefly in my Mar. 25, 2013 posting which featured excerpts from an interview with biotechnologist Christoph Meili about nanotechnology-enabled food packaging.

Nano sense of snow

According to a Dec. 19, 2012 news item on Azonano there’s a nanotechnology-enabled sensor which can identify snow depth,

Snow is the be-all and end-all for alpine ski resorts. Now a tiny sensor has been developed to determine how much cold gold there is on the slopes and how much more should be produced. The sensor is based on Norwegian radar technology and is no larger than a match head.

The processor chip from Novelda is the result of high-level nanotechnology. The minuscule Norwegian-designed silicon chip has already become an international success. Customers around the world are creating applications based on the technology.

The US-based company Flat Earth has drawn on Novelda’s technology to develop the SDS-715 snow-depth sensor. [emphasis mine] It is capable of measuring snow depth from 15 cm to 2 m with a margin of error of 3.5 cm.

The sensor is mounted beneath the vehicle that prepares the tracks. Snow depth is measured at one-second intervals. A separate application can be used to display snow depths via Google Earth.

There are widespread applications for the nanoscale sensor. Eirik Næss-Ulseth, Chairman of the Board in Novelda, envisions integrating the chips into athletic garments to replace pulse sensors that are currently held in place with an elastic band.

“We have already proven that the chips can be used to measure pulse and breathing rates at a distance,” he explains.

Novelda was founded as a spin-off company from the University in Oslo. …

The Research Council of Norway provided the Dec. 17, 2012 news release, written by Siw Ellen Jakobsen/Else Lie and translated by Glenn Wells/Carol B. Eckmann, which originated the news item. Oddly, Novelda issued a June 5, 2011 news release about a similar, if not identical, product,

Flat Earth Incorporated announced today they have developed the first mobile snow depth sensor based on the Novelda AS NVA6000 CMOS impulse radar chip. The SDS-715 provides a non-contact approach for determining snow depth on the go. [emphasis mine] Measurement range is 0.15 to 2.0 meters with an accuracy of approximately 3.5 cm, snow condition dependent.

This rugged low cost snow depth measurement system is designed for snow grooming operations at Alpine and Nordic ski resorts. Snow depth beneath the snowcat is measured every second, approximately every 3 meters at 8 kmph. The SDS-715 is cheaper than current ground penetrating radar systems on the market today. When used with Flat Earth’s CatWorks Snowcat navigation and information system, depth maps of the resort trails can be created and viewed in Google Earth.

For those new to marketing and promotion, it never hurts to reissue or send more information about a previously announced product, especially when it can be tied in with a season. Still, this is a bit longer than usual between campaigns.

For anyone interested in Flat Earth; nanoscale radar products and consulting, the company’s website is under construction and due to be unveiled sometime December 2012 (or, later this month).

Nanocanaries don’t die

It’s upsetting to think about the canaries in the mines singing to their heart’s content only to topple over and die when toxic gases make their presence felt during the mining process. The alternative, of course, is to sacrifice miners. Thankfully, choosing the lesser of two evils will no longer be necessary (actually, I don’t they’ve used canaries in quite a while) as scientists work on sensors that can detect any number of things not just toxic gases in the mines. The University of Massachusetts at Lowell is the latest to announce work on sensors (from the Nov. 15, 2012 news item on Nanowerk),

To detect the toxicity of engineered nanomaterials, such as carbon nanotubes, on living cells, electrical engineering Assoc. Prof. Joel Therrien — along with biology Prof. Susan Braunhut, chemistry Prof. Kenneth Marx and work environment Asst. Prof. Dhimiter Bello — has developed a “nanocanary,” the modern-day, high-tech equivalent of the canary in a coal mine that warned miners of dangerous buildups of toxic gases in the mine shaft.
The nanocanary is an ultrasensitive biosensor designed to continuously monitor tiny physiological changes in the live cells contained within it.

The Nov. 14, 2012 news release by Edwin L. Aguirre, which originated the news item, mentions a recent podcast by one of the researchers (Joel Therrien),

In a recent podcast produced by the Museum of Science in Boston, Therrien talked about the importance of studying how nano-sized particles affect human health and the environment as well as in the safe development of commercial nano products.

“Our biosensor has a wide range of applications, from testing for toxicity in nanomanufacturing to drug development and customized cancer therapeutics,” notes Therrien.

“In testing the toxicity of carbon nanotubes, for example, since the sensor can directly detect adverse effects on living cells, we are able to identify the threshold concentration at which carbon nanotubes lead to the cells’ death,” he explains. “The sensor can also be used to test the response of normal and cancerous cells to drug therapies. In the future, this technology may help guide oncologists in selecting the most appropriate drug for a cancer patient. We also see the potential for this to partially replace animals in testing drugs and other products.”

Therrien’s 16 min. podcast can be heard here.