Engineers develop a new biosensor chip for detecting DNA mutations

Bioengineers at the University of California, San Diego have developed an electrical graphene chip capable of detecting mutations in DNA. Researchers say the technology could one day be used in various medical applications such as blood-based tests for early cancer screening, monitoring disease biomarkers and real-time detection of viral and microbial sequences. The advance was published June 13 in the online early edition of Proceedings of the National Academy of Sciences.

“We are at the forefront of developing a fast and inexpensive digital method to detect gene mutations at high resolution—on the scale of a single nucleotide change in a nucleic acid sequence,” said Ratnesh Lal, professor of bioengineering, mechanical engineering and materials science in the Jacobs School of Engineering at UC San Diego.

The technology, which is at a proof-of-concept stage, is a first step toward a biosensor chip that can be implanted in the body to detect a specific DNA mutation—in real time—and transmit the information wirelessly to a mobile device such as a smartphone or laptop.

The team led by Lal, who serves as co-director for the Center of Excellence for Nano-Medicine and Engineering, a subcenter of the Institute of Engineering in Medicine (IEM) at UC San Diego, and Gennadi Glinsky, a research scientist at IEM, developed a new technique to detect the most common genetic mutation called a single nucleotide polymorphism (SNP), which is a variation of a single nucleotide base (A, C, G or T) in the DNA sequence. While most SNPs have no discernable effect on health, some are associated with pathological conditions such as cancer, diabetes, heart disease, neurodegenerative disorders, autoimmune and inflammatory diseases.

Current SNP detection methods are relatively slow, expensive and require the use of cumbersome equipment. “We’re developing a fast, easy, inexpensive and portable way to detect SNPs using a small chip that can work with your cell phone,” said Preston Landon, a research scientist in Lal’s research group and co-first author on the PNAS paper.

The chip consists of a DNA probe embedded onto a graphene field effect transistor. The DNA probe is an engineered piece of double stranded DNA that contains a sequence coding for a specific type of SNP. The chip is specifically engineered and fabricated to capture DNA (or RNA) molecules with the single nucleotide mutation—whenever these pieces of DNA (or RNA) bind to the probe, an electrical signal is produced.

The chip essentially works by performing DNA strand displacement, the process in which a DNA double helix exchanges one strand for another complementary strand. The new complementary strand—which, in this case, contains the single nucleotide mutation—binds more strongly to one of the strands in the double helix and displaces the other strand. In this study, the DNA probe is a double helix containing two complementary DNA strands that are engineered to bind weakly to each other: a “normal” strand, which is attached to the graphene transistor, and a “weak” strand, in which four the G’s in the sequence were replaced with inosines to weaken its bond to the normal strand. DNA strands that have the perfectly matching complementary sequence to the normal strand—in other words, strands that contain the SNP—will bind to the normal strand and knock off the weak strand. Researchers engineered the chip to generate an electrical signal when an SNP-containing strand binds to the probe, allowing for quick and easy SNP detection in a DNA sample.

Detailed report can be found from UCSD website by following this link.

Masimo Announces FDA Clearance for O3 Regional Oximetry

Masimo announced that it had received FDA 510(k) clearance for O3™ regional oximetry. Regional oximetry, also referred to as tissue or cerebral oximetry, may help clinicians monitor cerebral oxygenation in situations in which pulse oximetry alone may not be fully indicative of the oxygen in the brain due to various factors, such as the type of clinical procedure being performed.


O3 regional oximetry uses near-infrared spectroscopy (NIRS) to continuously monitor absolute and trended regional tissue oxygen saturation (rSO2) in the cerebral region. In a study on 27 subjects published in Anesthesia and Analgesia in 2014, Dr. Daniel Redford of the University of Arizona compared cerebral oxygen saturation measurements obtained from O3 with saturations obtained from blood samples (SavO2) through induced hypoxia.1 O3 regional oximetry provided absolute root-mean-squared error of 4% and relative root-mean-squared error of 2.1%.1 This study did not require that end tidal carbon dioxide (EtCO2) levels be fixed in the study protocol, allowing the rSO2 measurement to be responsive to changes in tissue oxygen saturation due to changes in CO2 in the blood. Follow up studies with O3 extended the subject pool to 74 subjects and demonstrated that O3 maintained its absolute and relative accuracy.2

“O3 regional oximetry delivers again on Masimo’s technical prowess and gives clinicians access to valuable, accurate data about cerebral oxygen saturation,” stated Joe Kiani, Founder and CEO of Masimo. “With the addition of O3 regional oximetry to the Root platform, clinicians can simultaneously access rSO2 and other measurements including SedLine brain function monitoring, Masimo SET SpO2, PVI, and SpHb monitoring – all in one monitoring platform.”

O3 regional oximetry is currently intended for use with adults weighing 40 kg (88 lbs) or greater.

More information can be found from Masimo website by following this link.

Male Fertility Testing System Gets FDA Approval

Sandstone Diagnostics announced that the U.S. Food and Drug Administration (FDA) has issued 510(k) clearance for the company’s Trak Male Fertility Testing System.


“This FDA clearance represents a monumental milestone for Sandstone Diagnostics as we prepare to launch Trak as a radically new approach to personal fertility management,” said Greg Sommer, Sandstone CEO. “Male infertility is a dramatically under-appreciated condition affecting millions of couples every year. Trak is a complete system that not only gives couples the ability to conveniently measure semen quality at home, but also provides digital health tools and population-based data to help men take charge of their reproductive health in a whole new way.”

Data suggest that men contribute to up to half of all infertility cases, but couples currently have very few options for tackling the male half of the conception equation 1. Today’s standard practice of medical evaluation by clinical semen analysis done in an office setting is generally viewed as an awkward and embarrassing experience for men, which further contributes to low rates of male evaluation and treatment.

Trak, which will be available for purchase beginning October 2016, is an in-home test that allows couples to measure and track sperm count conveniently and privately as they try to conceive. The innovative design uses centrifugal force to isolate and quantify sperm cells using specially designed disposable cartridges. The system includes the Trak Engine and several disposable test kits for repeat testing.

Trak is the first device cleared by the FDA that provides semi-quantitative results, classifying sperm counts as “Low”, “Moderate” or “Optimal” based on World Health Organization guidelines and clinical studies that correlate higher sperm counts with faster time to pregnancy. A fully-integrated digital health system, the Trak System pairs with the Trak mobile app (available free on Google Play, the Apple App Store and Amazon), to allow men to enter, track and compare their results to population statistics via the cloud-based community of users and clinical databases, and receive personalized feedback on lifestyle and wellness steps that may boost their sperm count.

“This is a game changer for men’s health,” said Michael Eisenberg MD, director of Male Reproductive Medicine & Surgery at Stanford University Medical Center. “Sperm count provides a window into a man’s overall health and it’s very exciting to see a technology that lowers the barrier for men to get tested, see changes and address fertility concerns. I believe with the convenience and availability of in-home testing, we are poised to improve our understanding of male fertility and empower men to better manage their health.”

More information can be found from Sandstone website.

Compound eye for high-density 3D imaging

Prof. Lee Wing-bun and his research team at the Department of Industrial and Systems Engineering of The Hong Kong Polytechnic University have developed a system named “Compound eye for high-density 3D imaging”. This innovation was inspired by the physiological structure of flies’ compound eyes. Applying ultra-precision rolled plate machining technology, this low-cost system realises higher quality of images.

Adopting microlens arrays composed of 12,000 microlens, the technology can acquire realistic 3D images of objects at both near and far fields and achieve “shoot first, focus later” effect. By processing the captured images, this technology provides a solution for image distortion caused by conditions such as insufficient light and inadequate resolution.

This technology can be broadly applied in imaging applications, including high precision surface profile, displacement and velocity measurements. In future, such type of lens can be used for optical cameras for medical devices, Lytro cinema cameras, 3D scanners, as well as the production of 3D images and movies etc.

The invention won a Gold Medal and the Prize of Association “Russian House for International Scientific and Technological Cooperation” at the 44th International Exhibition of Inventions of Geneva.

More information can be found from The Hong Kong Polytechnic University website.

Transapical access and closure device receives CE approval

Micro Interventional Devices announced that it received CE Mark approval for the Company’s first product: Permaseal™ transapical access and closure device. The Permaseal device allows surgeons to access and close the left-ventricle instantaneously, reliably and without suturing the myocardium. Permaseal is the world’s first device using compliant soft-tissue PolyCorTM anchor technology.

Permaseal was validated in the STASIS Clinical Study (Secure Transapical Access and Closure Study) conducted at five European Sites. Results indicated that Permaseal shortened operating time and hospital stay, reduced adverse events including the need for transfusion and reduced 12-month mortality and stroke rates to 0%. The technology provides a direct, safe and simple, access and closure site for emerging complex structural heart disease procedures including TAVR, TMVR, PFO, and other minimally invasive cardiac procedures.

“The CE Mark approval of Permaseal is a tremendous achievement for MID,” said Michael Whitman, MID’s Founder, President & CEO. “Permaseal is the first in a series of products designed to replace the need for suturing in structural heart procedures. We are excited that this technology is now available to our European surgeons and their patients.”

“In the near future, PolyCor and MyoLastTM technologies will be utilized in a broad range of proprietary, catheter-based products, addressing unmet needs in tricuspid repair, mitral repair and mitral valve fixation,” added Whitman. “MID’s technology platform enables open-surgical procedures to be performed percutaneously.”

Permaseal is currently the only transapical access and closure device available for commercial use in the EU. FDA clearance to market Permaseal is pending.

Product information can be found from MID website by following this link.

The smallest robust eye tracker

For someone who is unable to use their hands or fingers, eye tracking is one of the quickest, easiest and most ergonomically sound ways to operate a computer. The PCEye Mini lets people surf the web, connect with friends online, play games, Skype, turn on the lights or TV, and even make spreadsheets and documents, using only the eyes. Ultimately, the PCEye Mini gives people greater personal freedom and independence.

  

With PCEye Mini, clicks and navigation becomes more intuitive, creating a relaxed and natural computing environment. Because of its simple magnetic mounting bracket and convenient USB connection, the PCEye Mini easily attaches and detaches from a computer. It is also easily transported and able to be used with different computers, like at work or in school. All processing for the eye tracker is done on the device itself and doesn’t slow down the computer. This means that one does not need the latest, most expensive desktop or laptop in order to use the PCEye Mini.

Product details can be found from Tobii Dynavox website.