Stretchable, degradable semiconductors for health monitoring

Zhenan Bao has developed stretchable, degradable semiconductors, with the ability to conform to internal organ surfaces, and dissolve and disappear when no longer needed.

This is the first example of a material that simultaneously possesses the three qualities of semiconductivity, intrinsic stretchability and full degradability. Other attempts resulted in semiconductors that either did not break down completely, or had reduced electrical performance when stretched.

Zhenan Bao has solved this problem – by combining a rubbery organic polymer with a semiconducting one.

Her team synthesized and mixed the two degradable polymers, which self-assembled into semiconducting nanofibers embedded in an elastic matrix. Thin films made of these fibers could be stretched to twice their normal length without cracking or compromising electrical performance. When placed in a weak acid, the new material degraded completely within 10 days.   (Bao said that it would take much longer in the human body.) The semiconductor was  non-toxic to human cells growing on the material in a petri dish.


Zhenan Bao will discuss this technology, and more of her latest work, at Wearable Tech + Digital Health + Neurotech Silicon Valley on Feb 11-12

Sweat sensor monitors metabolites to detect gout, metabolic and other disorders

Caltech’s Wei Gao has developed a wearable sensor that monitors metabolites and nutrients in blood by analyzing sweat. Previously developed, less sensitive, sweat sensors mostly target electrolytes, glucose, and lactate.

Gao develops devices based on microfluidics, which minimize the influence of sweat evaporation and skin contamination on sensing accuracy.  Previous microfluidic-based wearable sensors were mostly fabricated with a lithography-evaporation process, requiring  complicated and expensive fabrication processes. Gao uses graphene.

In a study, the sensor was used to measure respiratory rate, heart rate, and levels of uric acid and tyrosine. Tyrosine can indicate metabolic disorders, liver disease, eating disorders, and neuropsychiatric conditions. Elevated Uric acid is associated with gout.

Gao believes that the high sensitivity of the sensors, and  the ease with which they can be manufactured, could enable them to be used at home to monitor gout, diabetes, and cardiovascular diseases.


Professor Gao will be a featured speaker at Wearable Tech + Digital Health + Neurotech Silicon Valley on February 11-12, 2020.

Wireless, wearable sticker adds a sense of touch to VR

John Rogers, Yonggang Huang and Northwestern colleagues have developed an “epidermal VR” system that adds a sense of touch to any virtual reality experience.

The device incorporates a distributed array of 32 individually programmable, millimeter-scale actuators, each of which generates a discrete sense of touch at a corresponding location on the skin. Each resonates most strongly at 200 cycles per second, where the skin exhibits maximum sensitivity. The actuators are embedded into a soft silicone polymer that adheres to the skin without tape or straps. The wireless, battery-free, device communicates with a phone or tablet through near-field communication protocols.

When a user touches the screen, that pattern of touch transmits to the patch. When video chatting from different locations, users can feel each other’s touch.

The next generation will be slimmer and lighter, with actuators that can produce heating and stretching sensations.  They will eventually  be thin and flexible enough to be woven into clothes.

Click to view Nature video


Join ApplySci at the 13th Wearable Tech + Digital Health + Neurotech Silicon Valley conference on February 11-12, 2020 at Quadrus Sand Hill Road.  Speakers include:  Zhenan Bao, Stanford – Vinod Khosla, Khosla Ventures – Mark Chevillet, Facebook – Shahin Farshchi, Lux Capital – Carla Pugh, Stanford – Nathan Intrator, Tel Aviv University | Neurosteer – Wei Gao, Caltech – Sergiu Pasca, Stanford – Rudy Tanzi, Harvard – Sheng Xu, UC San Diego – Dror Ben-Zeev, University of Washington – Mikael Eliasson, Roche  – Unity Stoakes, StartUp Health

 

 

 

 

Study: Focused ultrasound reduced essential tremor symptoms for 3 years

In a recent study, Casey Halpern and  colleagues used ultrasound to relieve symptoms of essential tremor, for up to three years. The treatment is used when medication does not work.

76 people with an average age of 71 who had essential tremor for an average of 17 years were studied. 56  received focused ultrasound thalamotomy, and 20 had a sham therapy. After three months, those who received the sham were offered the treatment. 23 people left the study. The researchers believe that those who left did not respond as well as others to the treatment.

Hand tremors, level of disability and quality of life were measured at the start, and after six months, one year, two years and three years. After three years, on average, participants improved in hand tremors by 50 percent, disability by 56 percent, and quality of life by 42 percent.

No new side effects occurred. Existing side effects, which continued during the study, included numbness and tingling, imbalance and unsteadiness.  The researchers claimed that none worsened, and two were resolved, during the treatment.

Current recommended treatment for people with severe essential tremor responding insufficiently to medication is deep brain stimulation. Ultrasound is much less invasive, performed in one session. There is no need for follow-up visits, and there is immediate benefit.  Ultrasound does, however, produce an irreversible brain legion.

Cala Health has also developed a non-invasive therapy for essential tremor, using a neuromodulation wearable on the wrist. The device  stimulates nerves responsible for the tremor, interrupting circuits, to allow for better movement control.


Join ApplySci at the 13th Wearable Tech + Digital Health + Neurotech Silicon Valley conference on February 11-12, 2020 at Quadrus Sand Hill Road.  Speakers include:  Zhenan Bao, Stanford – Vinod Khosla, Khosla Ventures – Mark Chevillet, Facebook – Shahin Farshchi, Lux Capital – Carla Pugh, Stanford – Nathan Intrator, Tel Aviv University | Neurosteer – Wei Gao, Caltech – Sergiu Pasca, Stanford – Rudy Tanzi, Harvard – Sheng Xu, UC San Diego – Dror Ben-Zeev, University of Washington – Mikael Eliasson, Roche

Silk patch measures 6 biomarkers in sweat

Wenya He, Yingying Zhang, and Tsinghua and Northwest School colleagues  have developed a silk-based wearable patch which measures glucose, ascorbic acid, lactate, potassium, sodium ions and uric acid concentrations in sweat.

Sensors are embedded in a woven graphite-silk fabric. Conductivity is enhanced using graphite doped with nitrogen atoms. The flexible patch is applied to the skin on the arm and used to collect data from sweat for the 6 biomarkers.

Epicore Biosystems, with technology developed by Roozbeh Ghaffari at Northwestern, and Eccrine Systems, spun out of Jason Heikenfeld’s work at University of Cincinnati, are rapidly advancing the use of sweat-monitoring wearables.


Join ApplySci at the 13th Wearable Tech + Digital Health + Neurotech Silicon Valley conference on February 11-12, 2020 at Quadrus Sand Hill Road.  Speakers include:  Zhenan Bao, Stanford – Vinod Khosla, Khosla Ventures – Mark Chevillet, Facebook – Shahin Farshchi, Lux Capital – Carla Pugh, Stanford – Nathan Intrator, Tel Aviv University | Neurosteer – Wei Gao, Caltech – Sergiu Pasca, Stanford – Rudy Tanzi, Harvard – Sheng Xu, UC San Diego – Dror Ben-Zeev, University of Washington – Mikael Eliasson, Roche

Remote, robotic surgery for aneurysm, stroke

Vitor Mendes Pereira at Toronto Western Hospital and Krembil Brain Institute .used a Siemens Healthineers-developed robot arm to help remove an aneurysm.  A catheter was guided to the patient’s brain from an incision made near the groin in the interventional procedure.

The CorPath GRX robotics platform is controlled by joysticks and a touchscreen. A bedside  technician interacts with the robot to exchange devices including guidewires, microcatheters, and coils.

The goal is the use of robots for remote stroke patient treatment.


Join ApplySci at the 12th Wearable Tech + Digital Health + Neurotech conference on February 11-12, 2020 at Quadrus Sand Hill Road.  Speakers include:  Zhenan Bao, Stanford – Vinod Khosla, Khosla Ventures – Mark Chevillet, Facebook – Shahin Farshchi, Lux Capital – Carla Pugh, Stanford – Nathan Intrator, Tel Aviv University | Neurosteer – Wei Gao, Caltech – Sergiu Pasca, Stanford – Rudy Tanzi, Harvard – Sheng Xu, UC San Diego – Dror Ben-Zeev, University of Washington – Mikael Eliasson, Roche

3D printed skin, with blood vessels

Pankaj Karande and Rensselaer Polytechnic Institute colleagues have developed 3D printed living skin, with blood vessels. which could integrate with host cells in grafts.

Until now, a significant barrier to integration has been the absence of a functioning vascular system.

Karande previously made two types of living human cells into “bio-inks,” and print them into a skin-like structure. He now includes human endothelial cells, which line the inside of blood vessels, and human pericyte cells, which wrap around the endothelial cells — with animal collagen and other structural cells typically found in a skin graft.

The cells start communicating and forming a biologically relevant vascular structure within the span of a few weeks. 

Karande said more work will need to be done to address the challenges associated with burn patients, which include the loss of nerve and vascular endings. But the grafts his team has created bring researchers closer to helping people with more discrete issues, like diabetic or pressure ulcers.

Click to view RPI video


Join ApplySci at the 12th Wearable Tech + Digital Health + Neurotech conference on February 11-12, 2020 at Quadrus Sand Hill Road.  Speakers include:  Zhenan Bao, Stanford – Vinod Khosla, Khosla Ventures – Mark Chevillet, Facebook – Shahin Farshchi, Lux Capital – Carla Pugh, Stanford – Nathan Intrator, Tel Aviv University | Neurosteer – Wei Gao, Caltech – Sergiu Pasca, Stanford – Rudy Tanzi, Harvard – Sheng Xu, UC San Diego – Dror Ben-Zeev, University of Washington – Mikael Eliasson, Roche

High resolution brain map traces wiring within, between, thalamus and cortex

Allen Institute scientists have created a high-resolution brain map, which traces thousands of connections between brain areas in mice, which they believe  can help us understand how brain circuitry changes in diseases and disorders such as Alzheimer’s disease and schizophrenia.

This is the most detailed map of connections in a mammalian brain to date, tracing neural wiring within and between the thalamus and cortex, responsible for higher level functions like memory, decision making, and understanding the world around us.

The study describes a high-resolution expansion of the Allen Mouse Brain Connectivity Atlas

Alterations in brain connections have been seen in Alzheimer’s disease, Parkinson’s and several other brain diseases and disorders.

Using a computational approach, the researchers found that different sections of the cortex and thalamus can be mapped into a hierarchy, much like a company’s org chart. Parts of the cortex that are specialized for information gathered via our senses, like vision and smell, are on the bottom rungs, and regions that handle more complicated input — like calling up a memory evoked by a familiar scent — are at the top. Connections flow both up and down the brain’s org chart, but the connections moving up are different than those moving down. They also found that not all connections respect these hierarchical laws. There are hints that the human cortex uses the same organizational system.

Allen Institute president Christof Koch said that “the next step will be to look directly at how neurons pass information through their electrical activity to confirm that this pattern matters.”


Join ApplySci at the 12th Wearable Tech + Digital Health + Neurotech Boston conference on November 14, 2019 at Harvard Medical School featuring talks by Brad Ringeisen, DARPA – Joe Wang, UCSD – Carlos Pena, FDA  – George Church, Harvard – Diane Chan, MIT – Giovanni Traverso, Harvard | Brigham & Womens – Anupam Goel, UnitedHealthcare  – Nathan Intrator, Tel Aviv University | Neurosteer – Arto Nurmikko, Brown – Constance Lehman, Harvard | MGH – Mikael Eliasson, Roche – Nicola Neretti, Brown – R. Jacob  Vogelstein, Camden Partners – Yael Mandelblat-Cerf, Biogen

November 14 – Harvard Medical School

Join ApplySci at the 12th Wearable Tech + Digital Health + Neurotech Boston conference on November 14, 2019 at Harvard Medical School featuring talks by Brad Ringeisen, DARPA – Joe Wang, UCSD – Carlos Pena, FDA  – George Church, Harvard – Diane Chan, MIT – Giovanni Traverso, Harvard | Brigham & Womens – Anupam Goel, UnitedHealthcare  – Nathan Intrator, Tel Aviv University | Neurosteer – Arto Nurmikko, Brown – Constance Lehman, Harvard | MGH – Mikael Eliasson, Roche – Nicola Neretti, Brown – R. Jacob  Vogelstein, Camden Partners – Yael Mandelblat-Cerf, Biogen

Pacifier sensor detects glucose levels in babies

UCSD’s Joe Wang has developed a soft, flexible, pacifier-based biosensor that continuously monitors glucose levels in saliva to detect diabetes in babies. Until now,  continuous glucose monitoring in newborns,  available only in major hospitals, requires piercing the infant’s skin to reach interstitial fluid.

The team created a proof of concept pacifier where small amounts of saliva were transferred through a narrow channel to a detection chamber.  An enzyme attached to an electrode strip converted glucose in the fluid to a weak electrical signal, which could be detected wirelessly by an app. The strength of the current correlated with the amount of glucose in saliva samples.

The preliminary analysis was conducted on adults with type 1 diabetes.  The pacifier detected changes in glucose concentrations in  saliva before and after a meal.

The device could also be configured to monitor other disease biomarkers.


Joe Wang will be a keynote speaker at ApplySci’s 12th Wearable Tech + Digital Health + Neurotech Boston conference on November 14, 2019 at Harvard Medical School.  

Other speakers include:  Brad Ringeisen, DARPA  – Carlos Pena, FDA  – George Church, Harvard – Diane Chan, MIT – Giovanni Traverso, Harvard | Brigham & Womens – Anupam Goel, UnitedHealthcare  – Nathan Intrator, Tel Aviv University | Neurosteer – Arto Nurmikko, Brown – Constance Lehman, Harvard | MGH – Mikael Eliasson, Roche – Nicola Neretti, Brown – R. Jacob  Vogelstein, Camden Partners – Yael Mandelblat-Cerf, Biogen