Inkjet-printed device helps monitor a patient’s blood sugar levels without painful needles.
A technique that enables biologically active enzymes to survive the rigors of inkjet printing presents a promising alternative to routine blood screening exams faced by diabetic patients. The KAUST-led team used this approach to make disposable devices that can measure glucose concentrations in human saliva.
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.
Bioscientist Sahika Inal collaborated with electrical engineer Khaled Salama and materials scientist Derya Baran to use inkjet technology to produce sensors sensitive to small sugar concentrations in biofluids.
Utilizing a commercial ink made from conducting polymers, the team printed microscale electrode patterns onto glossy paper sheets. Next, 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,” says Eloise Bihar, a postdoctoral researcher at KAUST and the first author of the study. “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.”
After optimizing the enzyme-printing conditions, the researchers had another obstacle to tackle. 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.
“Optimization never ends in engineering, so we are trying to make this system more robust to detect other metabolites in biofluids,” says Inal. “We are also looking to integrate printed and self-powered energy devices into the sensors, giving us a more user-friendly platform that eliminates external batteries or wires.”
The Latest on: Paper sensors
via Google News
The Latest on: Paper sensors
- The best electric stapleron October 12, 2019 at 3:03 pm
Some models can put out up to 40 staples per minute, which allows you to easily bind several packets. Some electric staplers have sensors and alert lights to tell you when you are low on staples or ...
- Ynvisible Interactive announces manufacturing Agreement with Invisense | IDTechEx Research Articleon October 11, 2019 at 12:00 pm
Starting 2019 the sensors will be deployed by SLD - Professional Roof Management Group ... The Twin-city region has been a leading hub in printed and paper-based electronics for over 25 years.
- Around the Web: Paper Back. Mechanical Paper. Graphene—Again! Gambling on RFID. Water Warning. Dog Talk. Real Robocop.on October 11, 2019 at 3:06 am
Over at the BBC, an episode of its Made on Earth series looks at how paper is making a comeback ... but it turns teal if a sensor detects pathogens and pink when those levels venture beyond safe ...
- Global Safety Sensors and Switches Market - Industry Chain Structure & Sales Price Analysis 2019-2028on October 10, 2019 at 5:18 am
Anti-collision Sensors, Others (material handling, conveyor systems, transport systems, assembling, packaging, automated guarded vehicles). Segmentation by end use industry: Automobile, Oil & gas, ...
- Airbus monitors toilet use in cabin sensor trialon October 9, 2019 at 4:07 pm
Airbus will use these sensors to track how many times the lavatory doors are opened and closed. This will give cabin crews a better idea of when to restock items such as toilet paper, hand towels and ...
- Transhumanism: You Can Now Have Electronic Sensor Tattoos Printed Onto Your Skinon October 8, 2019 at 10:00 pm
Much like paper, human skin is a delicate surface, and although electronic printing has been around for a while, scientists hadn't figured out a way to print on human skin. Earlier versions of ...
- Verizon, NEC use optical sensor technology to collect info on city trafficon October 7, 2019 at 11:44 pm
Verizon and NEC held a proof-of-concept field trial during which they managed to use network infrastructure with existing fibre optic cables already laid in the ground as distributed optical sensors ...
- Apple Patent Reveals work on Mixed Reality Applications for a Future Headset using advanced RBG-D Sensorson October 6, 2019 at 8:09 am
... Asus Xtion Pro Live uses RBG-D sensors as well. A 2012 paper on this could found here. Other books on this could be found here. In 2017 there was the PFTrack 2017 - RGBD Depth Sensor Support made ...
- Sensor fusion lets phone identify objects by simply knocking against themon October 3, 2019 at 10:08 pm
“It simply uses the built-in sensors on smartphones and takes advantage of the power of machine learning. It’s a software solution that everyday smartphone users could immediately benefit from.” He ...
- Methane sensors put on planes, trucks in oil production zoneon October 2, 2019 at 5:49 pm
Methane sensors will be put on planes, trucks and atop towers in the West Texas and southeastern New Mexico desert in a new effort to gauge the extent of greenhouse gas emissions from surging oil and ...
via Bing News