Researchers Develop Wearable Sensor for Detecting Atrial Fibrillation

Advanced devices developed by a mechanical engineering team at the University of Hong Kong (HKU) has proven to be useful for detecting potential stroke patients and helping machines mimic human brain functions.

In a collaboration with Nanjing University, Dr Paddy K.L. Chan, Associate Professor at the Department of Mechanical Engineering, developed a novel wearable electrocardiogram (ECG) sensor by integrating flexible, ultra-thin organic semiconductors into a flexible polyimide substrate. Powered by button battery, the sensor has outstanding signal amplification properties with a gain larger than 10,000, which allows it to detect electrophysiological signal, or f-wave with a frequency of 357 beats per minute (BPM), which indicates atrial fibrillation.

Conventional portable ECG sensors cannot easily detect the f-wave due to its weak amplitude. Atrial fibrillation is the most common arrhythmia associated with the increased risk of stroke or heart failure. The high signal detection capability stems from the ultralow subthreshold swing (SS) in the organic field effect transistors (OFETs).

Dr Chan’s study showed the ECG sensor managed to pick up unusual signals from patients with atrial fibrillation, while conventional electrodes could not.

“People wearing the new sensors can also enjoy freedom of movement, run around or even take a shower if they want, not being attached to a machine. We have seen a breakthrough in application with the use of a new device structure,” he said. The finding has been published in Nature Communications, in the article entitled “Sub-thermionic, ultra-high-gain organic transistors and circuits.”

Dr Chan’s previous breakthrough in developing the staggered structure monolayer OFETs, the material used in the latest experiment, was published in Advanced Materials. A US patent was also filed for the innovation. In the latest work, his team has advanced the application of the monolayer OFETs to flexible substrate for wearable electronic applications.

“The subthreshold swing is an important parameter in transistor or inverter operation as it implies how much voltage change is needed to turn the device from “off” state to “on” state. Our devices provide a record low subthreshold swing device which ensures low operating power and high sensitivity,” Dr Chan said.

His team also succeeded in adding ‘memory’ or collected signal, information to an organic transistor, which paves the way for advanced machine learning to mimic human brain functions.

The work has been published in Nature Communications, in another article entitled “Mimicking associative learning using an ion-trapping non-volatile synaptic organic electrochemical transistor”.

“Our paper explains the physics behind how information can be stored in a device,” said Dr Chan. “It sets the stage for the next generation of computer learning through the enhancement of the ‘learning function’ of a device. For example, we can integrate the memory transistors with optical sensors for image processing and computation at the same time. The memory transistors are building blocks for the artificial neural network that can perform signal recognition or learn like a human brain.”

Dr Chan’s team successfully added the “ion retainer” polytetrahydrofuran (PTHF) into a conductive organic polymer PEDOT:TOS. The PTHF can significantly slow down the move in-and-out of the ions in the PEDOT:TOS channel layer and maintain them at the desired conductance state. Multi-conductance levels, which can be considered as “memory levels”, were achieved. The experiment was held jointly with Northwestern University.

There is vast room for research in this area of human-machine interface, with unthinkable benefits for mankind. “There are unlimited possibilities when it comes to the applications of such interface,” added Dr Chan. In the meantime, however, he said that his focus would be on developing sophisticated circuit using advanced materials.

Source: HKU

Dutch Company Received Funding to Scale Up Cell Cultured Leather

Biotech company Qorium has raised €2.6 million in a funding round led by Brightlands Venture Partners. The funding will allow it to scale up its technology for producing cell cultured leather.

Founded in 2014, Qorium recently succeeded in developing proof of concept of its product. The cell cultured leather takes 99% less water and 66% less energy to produce than conventional leather.

It also eliminates the need for the first two phases of the tanning process, which are notoriously polluting. And since only a few bovine skin cells are required to produce the leather, the methane emissions produced by livestock could be vastly reduced.

“We look forward to providing real high-quality leather made in a dramatically more sustainable way than conventional leather,” said Stef Kranendijk, co-CEO and co-founder at Qorium. “This will be a game-changing, revolutionary transformation of the current leather market.”

Demand for leather alternatives is growing rapidly, with companies seeking to replace conventional leather in everything from car interiors to watch straps. By 2025, it’s estimated that the market will be worth $89.6 billion. But to date, most alt-leather companies have focused on plant-derived materials such as pineapple leaves and cactus skins.

“More and more users of leather, particularly the premium high-end brands in the leather fashion, footwear and automotive industry, want all the properties of real leather without the tremendously high negative impact on the environment that comes with livestock rearing,” said Rutger Ploem, co-CEO and co-founder at Qorium. “Qorium provides exactly that.”

Source: Vegconomist


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Graphene Can be Used to Detect COVID-19 Quickly, Accurately

Researchers at the University of Illinois Chicago have successfully used graphene — one of the strongest, thinnest known materials — to detect the SARS-CoV-2 virus in laboratory experiments. The researchers say the discovery could be a breakthrough in coronavirus detection, with potential applications in the fight against COVID-19 and its variants.

In experiments, researchers combined sheets of graphene, which are more than 1,000 times thinner than a postage stamp, with an antibody designed to target the infamous spike protein on the coronavirus. They then measured the atomic-level vibrations of these graphene sheets when exposed to COVID-positive and COVID-negative samples in artificial saliva. These sheets were also tested in the presence of other coronaviruses, like Middle East respiratory syndrome, or MERS-CoV.

The UIC researchers found that the vibrations of the antibody-coupled graphene sheet changed when treated with a COVID-positive sample, but not when treated with a COVID-negative sample or with other coronaviruses. Vibrational changes, measured with a device called a Raman spectrometer, were evident in under five minutes.

Their findings are published in the journal ACS Nano.

“We have been developing graphene sensors for many years. In the past, we have built detectors for cancer cells and ALS. It is hard to imagine a more pressing application than to help stem the spread of the current pandemic,” said Vikas Berry, professor and head of chemical engineering at the UIC College of Engineering and senior author of the paper. “There is a clear need in society for better ways to quickly and accurately detect COVID and its variants, and this research has the potential to make a real difference. The modified sensor is highly sensitive and selective for COVID, and it is fast and inexpensive.”

“This project has been an amazingly novel response to the need and demand for detection of viruses, quickly and accurately,” said study co-author Garrett Lindemann, a researcher with Carbon Advanced Materials and Products, or CAMP. “The development of this technology as a clinical testing device has many advantages over the currently deployed and used tests.”

Berry says that graphene — which has been called a “wonder material” — has unique properties that make it highly versatile, making this type of sensor possible.

Graphene is a single-atom-thick material made up of carbon. Carbon atoms are bound by chemical bonds whose elasticity and movement can produce resonant vibrations, also known as phonons, which can be very accurately measured. When a molecule like a SARS-CoV-2 molecule interacts with graphene, it changes these resonant vibrations in a very specific and quantifiable way.

“Graphene is just one atom thick, so a molecule on its surface is relatively enormous and can produce a specific change in its electronic energy,” Berry said. “In this experiment, we modified graphene with an antibody and, in essence, calibrated it to react only with the SARS-CoV-2 spike protein. Using this method, graphene could similarly be used to detect COVID-19 variants.”

The researchers say the potential applications for a graphene atomic-level sensor — from detecting COVID to ALS to cancer — continue to expand.

A provisional patent has been submitted based on this work.

Source: University of Illinois Chicago

Researchers Created the Vegan Spider Silk, a High-performance Film that Can be Used to Replace Single-used Plastics

Nicole Axworthy wrote . . . . . . . . .

Researchers from the University of Cambridge may have found a viable solution to single-use plastics: vegan spider silk. The new material is a synthetic polymer film that mimics the properties of spider silk, which is one of the strongest materials in nature. Because of its strength, the material could replace plastic in many common household products.

The vegan spider silk was created using a new approach for assembling plant proteins into materials that mimic silk on a molecular level. The energy-efficient method uses sustainable ingredients and results in a plastic-like, free-standing film, which can be made at an industrial scale. The material is also compostable, unlike other types of bioplastics which require industrial composting facilities to degrade.

A surprise finding

The researchers developed the material while studying something entirely different: proteins and Alzheimer’s disease. Tuomas Knowles, a University of Cambridge chemistry professor and lead researcher, was analyzing proteins to understand why, in some instances, proteins become malformed, leading to diseases and health problems in humans.

“We normally investigate how functional protein interactions allow us to stay healthy and how irregular interactions are implicated in Alzheimer’s disease,” Knowles said. “It was a surprise to find our research could also address a big problem in sustainability: that of plastic pollution.”

As part of their research, Knowles and his team became interested in why materials like spider silk are so strong when they have such weak molecular bonds, and they found that one of the key features that gives spider silk its strength is the hydrogen bonds, which are arranged regularly in space and at a very high density. The team also looked at how to replicate this feature in other plant proteins. They successfully replicated the structures found on spider silk by using soy protein isolate, a protein with a completely different composition. VegNews.SpiderWeb2

“Because all proteins are made of polypeptide chains, under the right conditions we can cause plant proteins to self-assemble just like spider silk,” Knowles said. “In a spider, the silk protein is dissolved in an aqueous solution, which then assembles into an immensely strong fibre through a spinning process which requires very little energy.” The researchers used soy protein isolate as their test plant protein, since it is readily available as a byproduct of soybean oil production.

A high-performance material

The new material can perform similar to high-performance engineering plastics such as low-density polyethylene. Its benefit is that it does not require chemical cross-linking, which is frequently used to improve the performance and resistance of biopolymer films. The most commonly used cross-linking agents are non-sustainable and can even be toxic.

“This is the culmination of something we’ve been working on for over 10 years, which is understanding how nature generates materials from proteins,” Knowles said. “We didn’t set out to solve a sustainability challenge—we were motivated by curiosity as to how to create strong materials from weak interactions.”VegNews.SpiderSilk

The new product will be commercialized by Xampla, a University of Cambridge spin-out company developing replacements for single-use plastic and microplastics. Later this year, the company will introduce a range of single-use sachets and capsules, which can replace the plastic used in everyday products like dishwasher tablets and laundry detergent capsules.

Source: Veg News

Robot Prints Custom Design Inside Drinks

Chris Albrecht wrote . . . . . . . . .

We’ve seen 3D printers create cake decorations, personalized vitamins, and even cultured beef. And now, thanks to Print a Drink’s robot, we’ve seen custom designs printed inside a cocktail. You might think such beverage witchcraft would be impossible. I mean, how could a design be suspended and hold its shape in anything other than a jello shot? Turns out it just takes the right drink, the right droplet and the precision of a robotic arm.

Based in Austria, Print a Drink has actually been around for three years. It was started by Benjamin Greimel as a university research project. Since that time, Print a Drink has created two working robots (one in the U.S. and one in Europe) that up until the pandemic would travel to special events and conferences printing out custom designs inside drinks at parties and such.

So how does it work? Print a Drink uses a robotic arm with a custom-made printer head attached to it. The robot uses a glass needle to inject a food-grade, oil-based liquid inside a drink. The drink itself needs to be less than 40 percent alcohol and can’t be a straight shot of something like vodka or whiskey because the injected beads won’t hold and will float to the surface. Greimel explained to me via video chat this week that the combination of liquid density, temperature and robotic movement allow the designs to last for roughly 10 minutes before dissipating.

Coordinating all those puzzle pieces is complicated to say the least. In addition to setting up the robot at an event and operating it, there are specific requirements around drinks that can be used, and designs need to be uploaded into the robot. Plus, there are safety concerns because the robotic arm does move about pretty quickly. Because of all those reasons, Print a Drink’s business has been around renting the robot ($2,500 – $5,000, depending on the event) and not selling them outright. In addition to all of the complications above, staff would need to be trained properly on how to use the machine, and chances are good that the people operating the devices are not roboticists who can troubleshoot.

To make Print a Drink more accessible, Greimel and his partner (the only two people at the company) have developed a smaller, self-contained version of the robot that is roughly the size of a countertop coffee machine. But don’t expect a consumer version for your next backyard soirée. This smaller version is still complicated, and still requires training, so the company is targeting large corporations like Disney or a hotel chain like Hilton where it could be installed and used for special events or promotions. Greimel said the first prototype of this smaller Print a Drink will be available in the next week.

Though more specialized, Print a Drink is part of a bigger automation movement happening with booze right now. In addition to robot-powered bars like Glacierfire popping up, we’re also seeing automated drink dispensing vending machines from Rotender and Celia start to hit the market. It’s not hard to see all of these types of robots working in tandem, however, with a robo-bartender pumping out standard cocktails, while Print a Drink prints up specialty drinks customized for special occasions. We’ll drink to that.

Source: The Spoon