Magnetic ink to make 3D printed, self-healing electronics a reality

A new magnetic ink has been developed that will be capable of being used to create self-healing batteries, electrochemical sensors and wearable, textile-based electrical circuits. The ink has already shown to repair more damage and at a quicker speed than current self-healing systems.

Developed by a team of engineers at the University of California San Diego, the ink’s key ingredient is microparticles that are oriented in a certain configuration by a magnetic field.

Because of the orientation of these particles, any tear in a device printed with the ink will self-heal as particles on both sides of the tear are magnetically attracted to one another.

The ink has already set records by repairing tears as wide as 3mm, a new high in the field of self-healing systems.

“Our work holds considerable promise for widespread practical applications for long-lasting printed electronic devices,” said Joseph Wang, director of the Center for Wearable Sensors and chair of the nanoengineering department at UC San Diego.

A demonstration of the magnetic ink, which was printed as a self-healing circuit onto a t-shirt, before being cut and repairing itself. Image courtesy of Jacobs School of Engineering/UC San Diego

A demonstration of the magnetic ink, which was printed as a self-healing circuit onto a t-shirt, before being cut and repairing itself

In addition to the extent of damage the ink allows devices to repair, it is also notable for its ability to do so without any outside catalyst.

Existing systems require external triggers to begin the healing process, and can take anywhere between a few minutes to several days to do so. By contrast, the new system requires no external trigger and repairs damage within roughly 50 milliseconds.

The engineers tested their system by printing batteries, electrochemical sensors and wearable, textile-based electrical circuits that they then set about damaging by cutting them and pulling them apart to create increasingly wide gaps. The devices were damaged nine times at the same location, as well as having damage inflicted in four different places on the same device.

Despite the extensive and repeated damage, the devices continued to heal themselves and recover function, losing only a minimal amount of conductivity.

For example, a self-healing circuit was printed on the sleeve of a T-shirt and connected to an LED light and a coin battery. The circuit and the fabric it was printed on were then cut, resulting in the LED turning off. Within a few seconds, however, it started turning back on as the two sides of the circuit came together and healed.

A second demonstation of the ink's healing capabilities. Image courtesy of Jacobs School of Engineering/UC San Diego

A second demonstration of the ink’s healing capabilities. Image courtesy of Jacobs School of Engineering/UC San Diego

“We wanted to develop a smart system with impressive self-healing abilities with easy-to-find, inexpensive materials,” said Amay Bandodkar, one of the papers’ first authors, who earned his Ph.D. in Wang’s lab and is now a postdoctoral researcher at Northwestern University.

The engineers envision that, in the future, they will be able to expand the range of applications for the ink by making use of different variations with different ingredients.

Additionally, they plan to test different self-healing ink recipes in silicon through computer simulations, before taking them for lab testing.

Adding stem cells to the brains of mice “slowed or reversed” ageing

Albert Einstein College of Medicine scientists “slowed or reversed” ageing in mice by injecting stem cells into their brains.

The study, published online in the journal Nature, saw the scientists implant stem cells into mice’s hypothalamus, which caused molecules called microRNAs (miRNAs) to be released.

The miRNA molecules were then extracted from the hypothalamic stem cells and injected into the cerebrospinal fluid of two groups of mice: middle-aged mice whose hypothalamic stem cells had been destroyed and normal middle-aged mice.

This treatment significantly slowed aging in both groups of animals as measured by tissue analysis and behavioural testing that involved assessing changes in the animals’ muscle endurance, coordination, social behaviour and cognitive ability.

“Our research shows that the number of hypothalamic neural stem cells naturally declines over the life of the animal, and this decline accelerates aging,” said senior author Dongsheng Cai, M.D., Ph.D., professor of molecular pharmacology at Einstein.

“But we also found that the effects of this loss are not irreversible. By replenishing these stem cells or the molecules they produce, it’s possible to slow and even reverse various aspects of aging throughout the body.”

To reach the conclusion that stem cells in the hypothalamus held the key to aging, the scientists first looked at the fate cells in the hypothalamus as healthy mice got older.

The number of hypothalamic stem cells began to diminish when the mice reached about 10 months, which is several months before the usual signs of aging start appearing. “By old age—about two years of age in mice—most of those cells were gone,” said Dr. Cai.

Images courtesy of the Mayo Clinic.

The researchers next wanted to learn whether this progressive loss of stem cells was actually causing aging and was not just associated with it.

To do this, the scientists observed what happened when they selectively disrupted the hypothalamic stem cells in middle-aged mice.

“This disruption greatly accelerated aging compared with control mice, and those animals with disrupted stem cells died earlier than normal,” said Dr. Cai.

Finally, to work out whther adding stem cells to the hypothalamus counteracted ageing, the scientists injected hypothalamic stem cells into the brains of middle-aged mice whose stem cells had been destroyed as well as into the brains of normal old mice.

In both groups of animals, the treatment slowed or reversed various measures of aging.

The scientists are now trying to identify the particular populations of microRNAs that are responsible for the anti-aging effects seen in mice, which is perhaps the first step toward slowing the aging process and successfully treating age-related diseases in humans.

Self-driving delivery cars coming to UK roads by 2018

A driverless vehicle designed to deliver goods to UK homes is set to take to the road next year after the successful conclusion of an equity crowdfunding campaign.

Developed by engineers at The University of Aberystwyth-based startup The Academy of Robotics, the vehicle, Kar-Go, is road-legal, and capable of driving on roads without any specific markings without human intervention.

Kar-Go has successfully raised £321,000 through Crowdcube – 107% of its goal – meaning the company now has the funds to build its first commercially ready vehicles. This amount will also, according to William Sachiti, Academy of Robotics founder and CEO, be matched by “one of the largest tech companies” in the world.

Images courtesy of Academy of Robotics

The Academy of Robotics has already built and tested a prototype version of Kar-Go, and is working with UK car manufacturer Pilgrim to produce the fully street-legal version.

The duo has already gained legal approval from the UK government’s Centre for Autonomous Vehicles, meaning the cars will be able to immediately operate on UK roads once built.

The aim of Kar-Go is to partner with suppliers of everyday consumer goods to significantly reduce the cost of deliveries, and the company’s goal in this area is ambitious: Sachiti believes Kar-Go could reduce delivery costs by as much as 98%.

Whether companies go for the offering remains to be seen, but the company says it is in early stage discussions with several of the largest fast-moving consumer goods companies in Europe, which would likely include the corporations behind some of the most recognisable brands found in UK supermarkets.

Introducing Kar-go Autonomous Delivery from Academy of Robotics on Vimeo.

While some will be sceptical, Sachiti is keen to drive the company to success, and already has an impressive track record in future-focused business development. He previously founded Clever Bins – the solar powered digital advertising bins found in many of the nation’s cities – and digital concierge service MyCityVenue – now part of SecretEscapes.

“As a CEO, it is one of my primary duties to make sure Kar-go remains a fantastic investment, this can only be achieved by our team producing spectacular results. We can’t wait to show the world what we produce,” he said.

“We have a stellar team who are excited to have begun working on what we believe will probably be the best autonomous delivery vehicle in the world. For instance, our multi-award winning lead vehicle designer is part of the World Championship winning Brabham Formula One design team, and also spent years as a Design Engineer at McLaren.”