Graphene sensors: introduction and market status - Page 44

Carbon Sciences, the U.S-based company focused on developing graphene-based technologies, recently declared that it is working on developing graphene-based fiber optics components, such as photodetectors, fiber lasers and optical switches.

The company stated that its goal has been to help unclog the existing bottlenecks and enable ultrafast communication in data centers for cloud computing. After further investigation, it has come to realize the enormity of the IT market and decided to focus creating unique solutions and products for this market.

Scientists at University College London (UCL) have identified a potentially faster way of moving molecules across the surfaces of graphene and other materials. The team carried out computer simulations of tiny droplets of water as they interact with graphene surfaces that reveal that the molecules can "surf" across the surface whilst being carried by the moving ripples of graphene.

The study shows that because the molecules were swept along by the movement of strong ripples in the carbon fabric of graphene, they were able to move at a fast rate, at least ten times faster than previously observed. It was also found that by altering the size of the ripples and the type of molecules on the surface, it's possible to achieve fast and controlled motion of molecules other than water.

The University of Cambridge has announced a rapid and low-cost method of printing conductive ink using graphene and other materials, which might facilitate the manufacturing of cost effective printed electronics, sensors and more.

Nanomedical Diagnostics, which declared the commercialization of a graphene biosensor in September 2015, announced the completion of a Series A financing round of $1.6 million. The funding round will enable the company to commercially release AGILE Research, its new label-free, quantitative, affordable research tool for small molecule and protein analysis. The company is also using the funds to lay the foundation for AGILE Lyme investigational product evaluation and market clearance.

Nanomedical Diagnostics states that it has achieved excellent progress in only 20 months, and that its current focus is finalizing AGILE Research product design. The company will be evaluating its performance with the CDC and Stanford University this fall and expects to launch the product early next year for commercial use to study proteins of interest.

Researchers at ICFO have shown that a 2D crystal, combined with graphene, has the capability to detect optical pulses with a response faster than ten picoseconds, while maintaining a high efficiency. This can lead to faster optical detectors that can be integrated into photonic circuits.

An important advantage of these devices based on graphene (and other 2D materials) is that they can be integrated monolithically with silicon photonics enabling a new class of photonic integrated circuits. Although this study has been focused on the intrinsic properties of the photo-detection device, the next step is to develop prototype photonic circuitry and explore ways to improve large-scale production of these devices.

Researchers from the Laboratory of Nanooptics and Plasmonics, Moscow Institute of Physics and Technology (MIPT) in Russia have devised a graphene oxide-based biosensor with the potential of significantly speeding up the process of drug development. Graphene helps to improve the sensor's sensitivity, which in the future may enable the development of new drugs and vaccines against many dangerous diseases like HIV, hepatitis and cancer.

The GO-based biosensors exploit the phenomenon of surface plasmon resonance (SPR). Surface plasmons are electromagnetic waves propagating along a metal-dielectric interface (like gold/air) and having the amplitudes exponentially decaying in the neighbor media. Adsorption of molecules from solution onto a sensing surface alters the refractive index of the medium near this surface and, therefore, changes the conditions of SPR. These sensors can detect biomolecule adsorption even at a few trillionth of a gram per millimeter square. Thanks to these merits, SPR biosensing is an outstanding platform to boost technological progress in the areas of medicine and biotechnology. Nevertheless, the most distinctive feature of such sensors is an ability to "visualize" molecular interactions in real time. Researchers believe that the introduction of this method into preclinical trials, for example, can completely change the pharmaceutical industry.

Nanomedical Diagnostics, a U.S-based biotech company developing and commercializing bioelectronics for use in research and diagnostics, launched its first product, AGILE Research, a label-free, quantitative, low-cost biosensor for small molecule and protein analysis. The product is entering beta testing this fall and planned for commercial release in early 2016.

AGILE Research is based on graphene biological field effect transistor (BioFET) technology. Its vision is enabling personalized healthcare by improving diagnostic ease, speed, and cost through cutting-edge capabilities. Nanomed’s current focus is finalizing AGILE Research product design and will be evaluating its performance with the Centers for Disease Control and Prevention (CDC) and Stanford University. The CDC and Nanomedical Diagnostics are entering into a Cooperative Research and Development Agreement to evaluate direct electronic detection of Borrelia burgdorferi antigens for a new Lyme disease diagnostic system. Lyme disease research is also a focal point in the Stanford beta test.

In a research funded by a U.S. Department of Defense-Multidisciplinary University Research Initiative grant and Wenzhou Medical University, an international team of scientists has developed what is referred to as the first one-step process for making seamless carbon-based nanomaterials that possess superior thermal, electrical and mechanical properties in 3D. The research may hold potential for increased energy storage in high efficiency batteries and supercapacitors, increasing the efficiency of energy conversion in solar cells, for lightweight thermal coatings and more. 

The group's early testing showed that a 3D fiber-like supercapacitor made with uninterrupted fibers of carbon nanotubes and graphene matched or even surpassed bettered the reported record-high capacities for such devices. When tested as a counter electrode in a dye-sensitized solar cell, the material enabled the cell to convert power with up to 6.8% efficiency and more than doubled the performance of a similar cell that used an expensive platinum wire counter electrode. 

Scientists at the University of Basel have managed to synthesize boron-doped graphene nanoribbons and characterize their structural, electronic and chemical properties. The modified material could potentially be used as a sensor for ecologically damaging nitrogen oxides.

Altering graphene sheets to nanoribbon shape is known as a way of inducing a bandgap, whose value is dependent on the width of the shape. To tune the band gap in order for the graphene nanoribbons to act like a silicon semiconductor, the ribbons usually undergo doping. That means the researchers intentionally introduce impurities into pure material for the purpose of modulating its electrical properties. While nitrogen doping has been realized, boron-doping has remained unexplored. Subsequently, the electronic and chemical properties have stayed unclear thus far.

Scientists at James Cook University in Queensland, Australia, and collaborators from institutions in Australia, Singapore, Japan, and the US have developed a new technique for growing graphene from tea tree extract. Graphene is only made of carbon atoms, so theoretically can be grown from any carbon source, but scientists are still looking for a graphene precursor and growth method that is sustainable, scalable, and economically feasible, since these are all requirements for realizing widespread commercialization of graphene-based devices.

In this study, the researchers have grown graphene from the tea tree plant Melaleuca alternifolia, a plant used to make essential oils in traditional medicine. They demonstrated that it is possible to fabricate large-area, nearly defect-free graphene films from tea tree oil in as little as a few seconds to a few minutes, whereas current growth methods usually take several hours. Unlike current methods, the new method also works at relatively low temperatures, does not require catalysts, and does not rely on methane or other nonrenewable, toxic, or explosive precursors.