Silver Circuits Create Conductive Fabric

Researchers at the National Physical Laboratory, Middlesex, UK, Electronics Interconnection group has developed a new method to produce conductive textiles, which could make integrating electronics into all types of clothing simple and practical by enabling circuits to be printed directly onto garments.

Smart fabric connected to a power source conducting electrical charge through a LED (Credit: Roya Ashayer-Soltani)

The researchers developed the technique for chemically bonding a nano-silver layer onto fibers. The silver is bound around individual fibers in each thread to give 100% coverage, with good adhesion and flexibility.

The nanosilver-coated fabric can be used in a wide range of applications, such as wound dressings, hygienic clothing, and medical applications where the presence of bacteria is hazardous. Since the conductive pattern is incorporated within the textile, the sensors are repeatedly positioned in the same location on the body.

Multiple electronic circuitry patterns can be placed on a garment in a single setup. For example, wireless wearable sensors for heart monitoring could overcome shortcomings of Holter monitoring and significantly improve diagnosis and treatment of cardiovascular diseases.

For more information, visit http://www.medicaldesignbriefs.com/component/content/article/17049.

Creating New Device Coatings from Cocoa Compounds

Natural products rich in polyphenols inspired a new form of antibacterial coating.

Researchers at Northwestern University, Evanston, IL, discovered that natural products, like green tea leaves, red wine, dark chocolate, and cacao beans could inspire antibacterial coatings. That’s because they all contain polyphenols, plant molecules that defend against bacteria and oxidative damage.

Since polyphenol compounds are sticky, the researchers used tannic acid and pyrogallol—inexpensive compounds resembling the more complex polyphenols in tea, wine, and chocolate to make new multifunctional coating materials that have antioxidant properties, are non-toxic, and can kill bacteria on contact.

The scientists say that the coatings can stick to virtually anything, including Teflon®, and could be used on a wide range of medical products, including catheters and orthopedic implants. The coatings have innate properties that, without further modification, can help prolong the life of a medical device, reduce inflammation in a patient, and prevent bacterial infections, they said. In addition, the coatings are only 20 to 100 nanometers thick, depending on the material being coated, so would not alter biomedical instruments in a negative way.

For more information, visit http://www.medicaldesignbriefs.com/component/content/article/17148.

Adding Color to 3D Medical Imaging

Researchers at Berkeley Lab and the University of Wisconsin- Milwaukee have reported the first full color infrared tomography. (Credit: Cait Youngquist)

A team of scientists from the U.S. Department of Energy’s Lawrence Berkeley National Laboratory and the University of Wisconsin, Milwaukee, have developed the first technique to offer full color infrared tomography. They say that they combined Fourier Transform Infrared (FTIR) spectroscopy with computed tomography scans to create a non-destructive 3D imaging technique that provides molecular-level chemical information with unprecedented detail of biological specimens with no need to stain or alter the specimen.

Every type of molecule absorbs infrared (IR) light at specific wavelengths. IR spectroscopy can identify the chemical constituents of a sample and the application of the Fourier-transform algorithm allows all IR fingerprints to be simultaneously recorded.

By combining FTIR with computed tomography, the researchers reconstructed 3D images out of multiple cross-sectional slices, to achieve what is believed to be the first demonstration of FTIR spectro-microtomography. This technology involves low-energy IR photons that do not affect living systems or require artificial labels, contrast agents, or sectioning.

For more information, visit http://www.medicaldesignbriefs.com/component/content/article/17050.

Micro-Machines for Bionic Devices

Caption: A microelectromechanical systems chip.

A team of electrical and mechanical engineers at Israel’s Tel Aviv University (TAU) has developed a way to print biocompatible components for microelectromechanical systems (MEMS), making them ideal for use in medical devices, like bionic prosthetic arms.

MEMS are usually fabricated from silicon using processes from the semiconductor industry. But, the TAU researchers are creating a novel micro-printing process that works using a highly flexible, non-toxic organic polymer. The resulting MEMS components, they say, can be more comfortably and safely used on or in the body.

MEMS sensors gather information from their surroundings by converting movement or chemical signals into electrical signals. MEMS actuators work in the other direction, converting electrical signals into movement. Both types of MEMS depend on micro- and nano-sized components, such as membranes, either to measure or produce the necessary movement.

TAU’s new printing process yields very flexible, paper-thin membranes made of a particular kind of organic polymer with specific properties that make it attractive for micro- and nano-scale sensors and actuators.

For more information, visit http://www.medicaldesignbriefs.com/component/content/article/17103.

Speeding Medical Imaging with Auto Lubricant

Shown is an experimental photodetector made out of amorphous silicon and molybdenum disulfide (MoS2). The two semiconductors form a high-speed photodetector. (Credit: Mohammad Esmaeili-Rad)

Scientists at the University of California, Berkeley, have built an experimental device that, they say, could speed up medical imaging using amorphous silicon and an engine lubricant called molybdenum disulfide, or MoS2. The two semiconductors form a high-speed photodetector.

Many photodetectors in large-area imaging devices use amorphous silicon since it absorbs light well and is relatively inexpensive to process. But, this type of silicon has defects that prevent the fast, ordered movement of electrons, leading to slower operating speeds and more exposure to radiation.

The engineers discovered that pairing a thin film of MoS2 with amorphous silicon speeds up collection of the photo-generated electrons. The combination forms a diode that results in a photoresponse rate 10 times faster than amorphous silicon alone.

Since these materials are easy and inexpensive to handle, the cost of speeding up photodetectors would be minimal, they say. MoS2 consists of individual nanosheets that can be used to make thin, novel electronic devices or to improve existing ones.

For more information, visit http://www.medicaldesignbriefs.com/component/content/article/17039.

Break Up to Make Up Stronger Materials

Microscopic tears can build stronger muscles and stronger materials.

Scientists at Duke University, Durham, NC, report that microscopic stresses and tears in a new kind of man-made material could help the substance bulk up like an athlete building muscle. They say that the new materials could be used to make better fluids or soft-structure substances like artificial heart valves.

The researchers say that this is the first time scientists have used force-induced chemistry within a material to make it stronger in response to stress. They first stressed one of the test materials by pulsing high-intensity sound waves through it, which created bubbles that typically collapse and break the bonds of the material’s molecules. The forces breaking atoms in the new materials, however, triggered the formation of new bonds, transforming the liquid into a gelatin- like consistency.

To test a putty-like material, the team used a twin-screw extruder, pulling the material through to destroying its molecular bonds and found that the material formed more new bonds than those destroyed.

For more information, visit http://www.medicaldesignbriefs.com/component/content/article/17080.