Scientists have developed disposable paper-based sensors that can measure glucose concentrations in saliva, paving the way for a pain-free alternative to diabetics for monitoring their blood sugar levels daily. Strips of pH-sensitive paper are commonly used to test whether a liquid is acidic or alkaline. Researchers are now working to apply similar principles to create paper sensors that quickly indicate disease biomarkers.
Key to this approach is replacing traditional electronic circuitry in the sensors with low-cost plastics that can be manufactured quickly and in large quantities.
A team from the King Abdullah University of Science and Technology (KAUST) in Saudi Arabia used inkjet technology to produce sensors sensitive to small sugar concentrations in biofluids.
Utilising a commercial ink made from conducting polymers, the team printed microscale electrode patterns onto glossy paper sheets.They printed a sensing layer containing an enzyme, glucose oxidase, on top of the tiny electrodes.
The biochemical reaction between available glucose and the enzyme creates electrical signals easily correlated to blood sugar levels.
“Paper is porous, which makes it challenging to print conducting and biological inks that are dissolved in water,” said Eloise Bihar, a postdoctoral researcher at KAUST. “Printing the enzyme is tricky, as well — it’s sensitive to variations of temperature, the voltage applied at the cartridge, and the pH of the ink,” said Bihar.
While fluids, such as sweat or saliva, contain enough sugar for monitoring purposes, they also contain molecules, such as ascorbic acid, that interfere electrically with conducting polymers.
Coating the sensor with a nafion polymer membrane that repels the negative charges present in most interfering species enabled measurement of only the relevant glucose levels in saliva samples from volunteers.
Experiments showed the top coating gave the sensor an unprecedented shelf life — the enzyme could be kept alive and active for a month if stored in a sealed bag.These results are encouraging the team to expand the capabilities of this approach by incorporating different enzymes into the sensing layer.
Xiaomi has been working on improvements for in-display fingerprint scanning
By Nancy Cohen
Fingerprint sensors—modern tools of convenience or awkwardly placed tools that are just plain difficult for instant use?
Aamir Siddiqui in XDA Developers is no stranger to the shortcomings in present-day in-display fingerprint scanners. He thinks they have “a long way to go before they can completely and perfectly replace the conventional fingerprint scanners,” but he foresees change.
“In-display fingerprint scanners are fast gaining popularity, and we are surely going to see a lot more of them in 2019. While the current generation in-display scanners may not be quicker or even more reliable than the conventional fingerprint scanners, future generations of this tech will continue to improve on these areas to provide a better experience.”
Better news does seem to be in the wings; The Verge’s Sam Byford, who covers Asia happenings, reported on in-display fingerprint sensors being worked on by Xiaomi.
The news revolves around a new type of in-display fingerprint scanner technology which has been confirmed by Xiaomi President and co-founder, Lin Bin. GSMArena similarly described a “next gen under display fingerprint scanner.”
The new sensor will solve one big issue, and that is being unable to unlock the phone without having to look at the screen. User to fingerprint sensor: Hey, you’re reading one tiny tiny area of my screen. Just.
“This means you have to be very specific about where you tap your finger, and makes it almost impossible to unlock your phone without looking at the display,” wrote Hadlee Simons in Android Authority.
Byford reported on a video demonstrating a prototype phone with a new fingerprint sensor that has an active area of 25 x 50mm. Translation: users could unlock it more easily by tapping, Byford said, “within a much larger region than the thumbprint-sized scanners found on several phones released last year.”
Siddiqui similarly noted that “Xiaomi claims that you can unlock the phone without looking at the screen now, which shows off their confidence in the larger recognition area.”
Bam-boom. “You can set up your finger with only one tap and then unlock the locked screen with pressing pretty much everywhere,” said GSMArena. Since the active authentication area is 25mm x 50.2mm, said Simons in Android Authority, “it’s an exponentially bigger area than that found on commercially available in-display fingerprint sensors right now.”
GSMArena added, “According to Lin Bin, the unlocking area is 50 mm by 25 mm, which is more than five times the UD area now and over 15 times the standard scanner on the back, used by Xiaomi.”
On Friday, Ajaay Srinivasan, The Mobile Indian provided some background: “The news comes from a video posted on Bin’s Weibo account which revealed the latest implementation of the advanced in-display fingerprint scanning technology. The video reveals a Xiaomi prototype device feature a new fingerprint unlock sensor which spans for an area that measures at 50 x 25 mm.”
Dates? Byford said Xiamoi president Lin Bin did not mention when such a device would become a shipping product.
GSMArena noted what Bin had to say moving forward. If it has a “great reception among fans, the company will consider placing the scanner in future devices.”
If you have ever fumbled around trying to access your fingerprint scanner, you will appreciate this video, posted on January 15, showing Xiaomi’s improved access design where unlocking does not mean you are required to look at the screen.
Beyond the obvious advantage of being able to access the scanner more easily on the screen, there is another plus that was noticed by Sahil Kapoor in iGyaan: “Notably, the fingerprint sensor appears to be very fast and accurate.”
Xiaomi Mijia Laser Projector 4K With 150-Inch Virtual Screen Launched in China
Although ordinary projectors are still a popular option, laser projectors have been gaining prominence in the last couple of years. These projectors are designed differently, allowing for a shorter throw area and the ability to project even in a well-lit room. The latest laser projector to make the news comes from Chinese electronics company Xiaomi through its Mijia brand. The company has launched the Xiaomi Mijia Laser Projector 4K in China, priced at CNY 9,999 (approximately Rs. 1,05,000). As the name suggests, the projector sports a 4K resolution on its virtual 150-inch screen projection.
The new Xiaomi Mijia Laser Projector 4K is the successor to the previous Mijia Laser Projector, which was previously priced at CNY 9,999 but came with a full-HD resolution. The latest product keeps the price and virtual screen size the same, but bumps up the resolution to 4K (3840×2160 pixels).
For now, the product is available as a pre-sale offer, and can be booked for an advance payment of CNY 100 (approximately Rs. 1,050). As with other laser projectors, the Xiaomi Mijia Laser Projector 4K can be placed near a wall or projector screen, and directly project onto it from a short throw. This allows for easier placement as compared to traditional long-throw projectors, along with a virtual screen size of up to 150 inches.
The Xiaomi Mijia Laser Projector 4K comes with built-in speakers, three HDMI ports, one USB port, and sockets for audio and Ethernet cables. You also get smart connectivity with the MIUI TV interface and a remote to control the projector. Unlike the TV range, the projector is a part of the Mijia brand from Xiaomi.
Ultimate Ears Boom 3 Wireless Speaker with ‘Magic Button’ Launched in India
Wireless speakers come in all shapes, sizes and prices, but there has been a tendency for certain products and brands to stand out from the competition. One such popular brand has been Ultimate Ears (UE), the personal audio manufacturer owned by Swiss computer peripherals manufacturer Logitech. The Boom range from Ultimate Ears has been among its most popular lines, and the latest product from the line is the Ultimate Ears Boom 3. The new wireless speaker has been launched in India, priced at Rs. 15,995.
The Ultimate Ears Boom 3 is set to go on sale on Amazon India starting January 17. The product will be available in three colour options – Black, Blue, and Red. The speaker comes with an IP67 water resistance rating, which means that it is certified to survive significant exposure to water and dust, and can therefore be used safely outdoors. Interestingly, the Ultimate Ears Boom 3 floats in water, a feature that would appeal to a lot of buyers.
Another new feature on the UE Boom 3 is the ‘Magic Button’, which is said to make music control and playback easier. The speaker does retain the cylindrical design of its predecessors, although the styling has been refreshed. However, the familiar ‘plus’ and ‘minus’ physical volume buttons are still there. The USB port has also been repositioned to make charging the speaker a bit easier.
As the successor to the capable Ultimate Ears Boom 2, the UE Boom 3 was launched in August last year globally, and has taken a few months to see a launch in India. Interestingly, the UE Boom 2 is also still on sale for around Rs . 10,000.