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Multi-Functionalization of Graphene for Molecular Targeted Cancer Therapy

Posted By Graphene Council, Thursday, April 23, 2020
“Three” kinds of regalia such as crown, orb, and sward are often necessary to be a high king for conquering the world. For fighting off cancerous diseases, what do we need? This “triple” chemical modified nanomaterial might be save the patient.

Cancer is a leading cause of death worldwide. Under this situation, a successful tumor selective drug targeting and minimized toxicity of cancer drug are urgently necessary.

Scientists from Japan Advanced Institute of Science and Technology (JAIST) and Centre national de la recherche scientifique (CNRS), and their colleagues have developed a type of nanomedicine based on multi-functional graphene that allows for targeted cancer treatment at molecular level.

Single molecular sheet graphene is a promising carbon nanomaterial for various fundamental and practical applications in the next decade because of its excellent physico-chemical features. Graphene has been also known to have a good biocompatibility and biodegradability, thus leading to explore this nanocarbon as drug delivery carrier. However, it is not easy to modify a lot of individual functional molecules onto a graphene nano-sheet at the same time for its biomedical applications.

Developed by Prof. Eijiro Miyako from JAIST (Nomi, Japan), Dr. Alberto Bianco from CNRS (Strasbourg, France), and their international teams, the multi-functional graphene as a drug delivery carrier are successfully synthesized with “three” type of molecules such as near-infrared (NIR) fluorescent probe (indocyanine green; ICG), tumor targeting molecule (Folic acid: FA), and anticancer drug (doxorubicin; Dox) by a covalent chemical modification technique (Figure 1). ICG (green color part in the picture) was chosen as fluorophore to follow the uptake and to track the material inside the cells. FA (blue) was covalently bound through a polyethylene glycol (pink) linked to graphene, to specifically target the cancer cells, and Dox (red) was used as anticancer drug.

Aside from testing the therapeutic abilities to eliminate cancer cells in a culture dish, the team found that the unique properties of this multi-functional graphene showed an enhanced anticancer activity with excellent cancer targeting effect. This would open the doors to future biomedical applications of this type of material. The team plans to continue exploring multi-functional graphene towards the cancer therapy using murine animal model.

Paper titled “Rational chemical multifunctionalization of graphene interface enhances targeting cancer therapy”, published in Angewandte Chemie International Edition, DOI: 10.1002/anie.201916112

The work was supported by the Japan Society for the Promotion of Science KAKENHI Grant-in-Aid for Scientific Research (A) and (B), the KAKENHI Fund for the Promotion of Joint International Research, the Agence Nationale de la Recherche (ANR), the Graphene Flagship, the Spanish MINECO, the Generalitat Valenciana.

Tags:  Alberto Bianco  CNRS  Eijiro Miyako  Graphene  Healthcare  JAIST  nanomaterials 

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Global First as Talga Graphene Coating Begins Commercial-Scale Trial on Ocean-Going Cargo Vessel

Posted By Graphene Council, Thursday, April 23, 2020
Advanced battery anode materials and graphene additives provider Talga Resources Ltd is pleased to announce the commencement of a commercial scale trial of a Talga graphene-enhanced coating applied to a 33,000t container ship. The result is expected to be a range of environmental and economic benefits, which for marine applications includes improved corrosion resistance, decreased metallic paint loss into oceanic ecosystems and increased efficiency through lowering dry-docking cycles.

Believed to be the world’s largest single application of graphene, the 700 m2 coating of the cargo vessel’s hull is part of advanced testing of Talga’s functionalised graphene (Talphene®) additive as a performance booster for existing commercial marine coatings (part of the global 54 million tonne per annum paint and coating market1). The commercial-scale application follows completion of in-house development and patent pending technology that successfully translates graphene’s exceptional mechanical properties into paint and coatings. The result is expected to be a range of environmental and economic benefits, which for marine applications such as shipping and offshore infrastructure includes improved corrosion resistance, decreased metallic paint loss into oceanic ecosystems and increased efficiency through lowering dry-docking cycles.

The freshly coated ship is now at sea and over the coming 12-18 months the Talphene-coated area will be evaluated in the harsh real-life conditions of global cargo shipping.

Talga Managing Director, Mr Mark Thompson: “The maritime coating sector is a very large market and well suited to use of our Talphene® graphene additives for improved environmental and economic outcomes. Additionally, by successfully taking this new product from the laboratory to commercial scale application on a 33,000 tonne ship, being tested across global marine environments, we are showcasing our graphene’s real-world potential as a bulk industrial product.” Marine coatings market

Within the global ~54 million tonne per annum paint and coatings market2, the marine coatings segment is projected to grow to USD$12 Billion by 2024. Drivers for new coating technologies include environmental and regulatory demands, fuel efficiency, construction costs (pre-fabrication) and maintenance costs. Growth in emerging economies such as China, India and Brazil are large volume drivers while in terms of value, the Asia Pacific marine coatings market is projected to grow at the highest CAGR during the forecast period3. Key players operating in the marine coatings market include Hempel (Denmark), Jotun (Norway), AkzoNobel (Netherlands), PPG Industries (US), Sherwin-Williams (US), Chugoku Marine Paints (Japan), Nippon Paint (Japan), Kansai Paint (Japan), Axalta (US), and BASF Coatings (Germany).

Talphene® coating product development

Coatings are one of Talga’s key target products due to the large volume market and graphene’s potential to provide substantial new levels of performance and environmental sustainability. For maritime applications, Talga’s additive development has included multi-stage testing to optimise graphene loadings (i.e. quantities) and Talga’s unique patent-pending dispersion technology for epoxy based commercial primer coating systems. Testing by Talga included industry accepted ASTM prescribed Salt Fog Test (ASTM B117) where steel panels coated with epoxy primer containing Talphene additive showed improved corrosion protection performance compared to ‘state of the art’ commercial systems currently used world-wide in large volumes.

Further evaluation included mechanical performance tests, carried out to ASTM standard by the highly recognised research organisation The Welding Institute (TWI), as the coated surfaces of ships and maritime infrastructure are exposed to considerable abrasion and mechanical damage during service. The results showed a significant improvement in primer performance, including greater adhesion to the substrate (by ~7%), greater interlayer adhesion to the subsequent (antifouling) coating systems (by ~14%) and consistent improvement in abrasion resistance.

These improvements in performance were a notable outcome for this highly optimised industry, indicating that graphene’s exceptional mechanical properties translated into the coating system and warranted commercial-scale trials.

Commercial ship application & trial details

Based on the successful lab results, plans were drawn up for a major commercial scale application and sea trial. A 2-part epoxy based commercial coating system was purchased and mixed with the Talphene additive before dispatch to the ship management company for application during vessel dry docking (carried out every ~5 years for ships this size). The test areas along the ship’s starboard side, both below the water line and above in contact-wear sites, were blast cleaned to remove prior paint systems before the Talphene-enhanced primer coating was applied (next to a test reference coating without Talphene) in two coats, using manual spray systems. A major challenge of the product development was to translate the positive lab-scale tests into practical, large-volume use by on-site commercial applicators. The successful application of the Talphene-enhanced coating without any adverse effect in terms of stability in resin, application, curing and surface features is a highly positive step forward in the commercialisation process. The test areas have been over-coated with the standard topcoats used on the rest of the vessel and marked to ensure identification during service. Periodic inspection will be carried out over the next 12-18 months to determine real world performance.

Next steps

Talga intends to continue development of this Talphene additive for marine coatings under its range of paint and coating additives now trademarked as Talcoat™. The next steps include a trial of the additive as an after-market product, to be mixed into the coatings on-site by the commercial applicators, as opposed to being dispersed by Talga prior to despatch. Talga has also identified a range of potential commercial partners and commenced discussions, under NDA, regarding the incorporation of Talcoat products into their existing and new coating product lines4. The company notes that these negotiations are preliminary, and further updates will be released as and when any definitive commercial agreements are reached.

Tags:  Coatings  Corrosion  Graphene  Mark Thompson  Talga Resources 

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Next Level Analysis for Haydale Functionalised Nanomaterials

Posted By Graphene Council, Wednesday, April 22, 2020
Haydale, the global advanced materials group, has been awarded an Innovate UK Analysis for Innovators (A4I) project to explore the mechanisms by which the Haydale plasma functionalisation processes enables property improvements in polymers containing functionalised nanomaterials; properties such as mechanical strength, thermal, and electrical conductivity.

The project enables Haydale to gain access to world leading experts and cutting-edge facilities by collaborating with the National Physical Laboratory (NPL) and the Science and Technology Facilities Council (STFC) Hartree Centre.

The data produced in this project will help Haydale build on the significant progress it has already made in this area. It will enable Haydale to focusthe development of its entire product range; allowing quick and efficient selection of improved functionalisation chemistries that can optimise the performance of its current products.

Haydale has a range of plasma functionalised nanomaterial (HDPlas®) products which are dispersed in a variety of polymers to enhance customer products. Numerous developments conducted within Haydale have demonstrated that the use of its patented HDPlas® plasma technology is effective in imparting specific functional groupsto the nanomaterial surface for improved compatibility within the host polymer. This nanomaterial surface functionality leads to property enhancements in the final products above and beyond the use of un-functionalised nanomaterials.

This project aims to uncover this mechanism using a dual approach of advanced analytical techniques at NPL and modelling at STFC Hartree Centre. The approach of using analytical facilities with complementary modelling will ensure that the highest level of information is obtained, and that any conclusions are drawn with a high level of confidence and accuracy, thereby potentially enabling product and process development.

Keith Broadbent, Haydale CEO,said: “Haydale has a wealth of knowledge and expertise which hasled to the patenting of its HDPlas® functionalisation process. This analysis by both NPL and STFC will provide more data and practical understanding enabling us to further understand where our nanomaterials will provide benefit and continue to develop our unique processes to ensure we keep in the vanguard of this technology”

Barry Brennan, NPL Senior Research Scientist, said: “Understanding the chemistry of nanomaterials after industrial processing steps is crucial in determining the performance-enhancement in real-world products. We look forward to collaborating with Haydale on their functionalisation process.”

Tags:  Barry Brennan  Graphene  Haydale  Keith Broadbent  nanomaterial  National Physical Laboratory 

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Gratomic Announces Amendment to Terms of Convertible Debentures and Further Debt Settlement

Posted By Graphene Council, Wednesday, April 22, 2020
Gratomic Inc. wishes to announce that it has amended the terms of the Debenture Units announced in the Press Release issued April 8, 2020 in relation to its engagement of First Republic Capital Corporation ("First Republic") to act as its exclusive lead finder in respect of a non-brokered private placement to raise up to CAD $2,250,000 (the "Offering").

First Republic will act as exclusive lead finder on a commercially reasonable efforts basis to sell up to $1,500,000 aggregate principal amount of convertible debenture units ("Debenture Units") on the amended terms described herein. The Debenture Units will consist of up to 1,500 senior secured convertible debentures, with each Debenture Unit priced at $1,000 consisting of (a) one $1,000 face value convertible debenture, convertible at the option of the holder into common shares of the Company (a "Share") at $0.06 per Share for the first twelve (12) months from the closing of the Offering ("Closing Date"), and thereafter at $0.10 for a further six (6) months, which will bear interest at 10% per year, paid quarterly in cash, until maturity, being 18 months form the Closing Date (a "Debenture Certificate"); and (b) 8,333 share purchase warrants ("Debenture Warrants") with each Debenture Warrant entitling the holder to purchase one additional Share at an exercise price of $0.10 per Share for a period of 18 months from the Closing Date. See the April 8, 2020 Press Release for further details of the Offering.

The Company also wishes to announce that it will settle an aggregate of a further $149,606.75 of debt owed to arm's length parties, one director and two entities related to insiders of the Company for the issuance of 2,493,444 Shares of the Company at a price of $0.06 per share (the "Further Debt Settlement").

All securities issued pursuant to the Offering and the Further Debt Settlement are subject to a statutory hold period of four months and a day following the Closing Date.

Closing of the Offering is expected to occur on or before mid-May 2020. The Offering and Further Debt Settlement are subject to certain conditions, including, but not limited to, the receipt of all necessary regulatory and stock exchange approvals, including the approval of the TSX Venture Exchange.

The insider debt settlements are exempt from the valuation and minority shareholder approval requirements of Multilateral Instrument 61-101 ("MI 61-101") by virtue of the exemptions contained in sections 5.5(a) and 5.7(1)(a) of MI 61-101 in that the fair market value of the consideration for the securities of the Company to be issued to insiders does not exceed 25% of its market capitalization.

Tags:  Graphene  Gratomic 

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High-quality boron nitride grown at atmospheric pressure

Posted By Graphene Council, Wednesday, April 22, 2020
Graphene Flagship researchers at RWTH Aachen University, Germany and ONERA-CNRS, France, in collaboration with researchers at the Peter Grunberg Institute, Germany, the University of Versailles, France, and Kansas State University, US, have reported a significant step forward in growing monoisotopic hexagonal boron nitride at atmospheric pressure for the production of large and very high-quality crystals.

Hexagonal boron nitride (hBN) is the unsung hero of graphene-based devices. Much progress over the last decade was enabled by the realisation that 'sandwiching' graphene between two hBN crystals can significantly improve the quality and performance of the resulting devices. This finding paved the way to a series of exciting developments, including the discoveries of exotic effects such as magic-angle superconductivity and proof-of-concept demonstrations of sensors with unrivalled sensitivity.

Until now, the most widely used hBN crystals came from the National Institute of Material Science in Tsukuba, Japan. These crystals are grown using a process at high temperatures (over 1500°C) and extremely high pressures (over 40,000 times atmospheric pressure). "The pioneering contribution by the Japanase researchers Taniguchi and Watanabe to graphene research is invaluable", begins Christoph Stampfer from Graphene Flagship Partner RWTH Aachen University, Germany. "They provide hundreds of labs around the world with ultra-pure hBN at no charge. Without their contribution, a lot of what we are doing today would not be possible."

However, this hBN growth method comes with some limitations. Among them is the small crystal size, which is limited to a few 100 µm, and the complexity of the growth process. This is suitable for fundamental research, but beyond this, a method with better scalability is needed. Now Graphene Flagship researchers tested hBN crystals grown with a new methodology that works at atmospheric pressure, developed by a team of researchers led by James Edgar at Kansas State University, US. This new approach shows great promise for more demanding research and production.

"I was very excited when Edgar proposed that we test the quality of his hBN", says Stampfer. "His growth method could be suitable for large-scale production". The method for growing hBN at atmospheric pressure is indeed much simpler and cheaper than previous alternatives and allows for the isotopic concentration to be controlled.

"The hBN crystals we received were the largest I have ever seen, and they were all based either on isotopically pure boron-10 or boron-11" says Jens Sonntag, a graduate student at Graphene Flagship Partner RWTH Aachen University. Sonntag tested the quality of the flakes first using confocal Raman spectroscopy. In addition, Graphene Flagship partners in ONERA-CNRS, France, led by Annick Loiseau, carried out advanced luminescence measurements. Both measurements indicated high isotope purity and high crystal quality.

However, the strongest evidence for the high hBN qualitycame from transport measurements performed on devices containing graphene sandwiched between monoisotopic hBN. They showed equivalent performance to a state-of-the-art device based on hBN from Japan, with better performance in some areas.

"This is a clear indication of the extremely high quality of these hBN crystals," says Stampfer. "This is great news for the whole graphene community, because it shows that it is, in principle, possible to produce high quality hBN on a large scale, bringing us one step closer to real applications based on high-performance graphene electronics and optoelectronics. Furthermore, the possibility of controlling the isotopic concentration of the crystals opens the door to experiments that were not possible before."

Mar García-Hernández, Work Package Leader for Enabling Materials, adds: "Free-standing graphene, being the thinnest material known, exhibits a large surface area and, therefore, is extremely sensitive to its surrounding environment, which, in turn, results in substantial degradation of its exceptional properties. However, there is a clear strategy to avoid these deleterious effects: encapsulating graphene between two protective layers."

García-Hernández continues: "When graphene is encapsulated by hBN, it reveals its intrinsic properties. This makes hBN an essential material to integrate graphene into current technologies and demonstrates the importance of devising new scalable synthetic routes for large-scale hBN production. This work not only provides a new and simpler path to produce high-quality hBN crystals on a large scale, but it also enables the production of monoisotopic material, which further reduces the degradation of graphene when encapsulated by two layers."

Andrea C. Ferrari, Science and Technology Officer of the Graphene Flagship and Chair of its Management Panel, adds: "This is a nice example of collaboration between the EU and the US, which we fostered via numerous bilateral workshops. Devising alternative approaches to produce high-quality hBN crystals is crucial to enable us to exploit the ultimate properties of graphene in opto-electronics applications. Furthermore, this work will lead to significant progress in fundamental research."

Tags:  Andrea C. Ferrari  Christoph Stampfer  Graphene  Graphene Flagship  Hexagonal boron nitride  Mar García-Hernández  ONERA-CNRS  optoelectronics  RWTH Aachen University  Sensors 

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Graphene Wearables: Exploring Next-Gen Electronics

Posted By Graphene Council, Wednesday, April 22, 2020
Wearable technology refers to any class of electronic items that can be comfortably worn on the body. This covers an ever-growing range of application and product segments, from health and fitness trackers to immersive infotainment systems. They are governed by many of the same principles and trends as other electronics markets, namely extremely high consumer demand for greater functionality in smaller formats. Developers are consistently tasked with miniaturizing devices without compromising on battery life or performance, which mandates next-generation material solutions like graphene sensors.

Graphene Wearable Electronics

The wearable electronics market continues to experience enormous commercial growth due to the release of coveted commercial goods like smartwatches and virtual reality (VR) headsets, contributing to an estimated compound annual growth rate (CAGR) of 15.5%. Provided the market continues to grow as expected, the global wearable electronics market will be worth over $67 billion by 2024.

Although commercialized wearable electronics are now well-cemented in the consciousness of global consumers, they occupy a novel segment of the market. Medical and military-grade wearables have been used routinely for years, while professional sports have exploited health and wellness trackers integrated into clothing for almost as long. Graphene wearable electronics are expected to bridge the gap between these more sophisticated market segments and consumers, allowing the general public to benefit from advanced functionality wearables in increasingly ergonomic formats.
 
Graphene Wearables: UV-Detection Patch

One interesting graphene wearable prototype is a flexible, transparent substrate that can be directly applied to the wearer’s skin. The patch detects and monitors exposure to ultraviolet (UV) rays and, with advanced internet of things (IoT) connectivity, and can alert the user once they have reached a pre-defined threshold of exposure to sunlight. This could help prevent a range of harmful conditions, from sunburn to melanoma.

Graphene-Based Health & Wellness Sensors

Using the same key technology as the previous application, researchers are increasingly hopeful of integrating graphene-based sensors and substrates into fitness trackers with unprecedented levels of functionality. Currently, commercial devices such as smartwatches often feature rudimentary heart-rate monitors based on infrared (IR) sensors, and movement trackers based on integrated accelerometers.

With superior biocompatibility, graphene sensors could offer more detailed insights into a wide range of health and wellness signals, including hydration, oxygen saturation, continuous blood pressure monitoring and temperature.  Additionally, graphene sensors are being developed for pregnant mothers in the form of a wearable patch, that can monitor and track fetal movements in real time, sending potential indicaitons of a problem to medical professionals.

Graphene Sensor Materials from Grolltex

Grolltex is one of the industry-leading producers of single-layer graphene for sensor applications. We utilise a proprietary chemical vapour deposition (CVD) methodology to produce monolayer materials on substrates of your choosing. We are increasingly servicing researchers and product developers with graphene solutions for sensor and wearable applications and are eager to see how the market progresses in the coming years.

Tags:  chemical vapour deposition  Graphene  Grolltex  nanoelectronics  Sensors 

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New 'brick' for nanotechnology: Graphene Nanomesh

Posted By Graphene Council, Wednesday, April 22, 2020
Researchers at Japan advanced institute of science and technology (JAIST) have successfully fabrication the suspended graphene nanomesh in a large area by the helium ion beam microscopy. 6nm diameter nanopores were pattern on the 1.2 um long and 500 nm wide suspended graphene uniformly. By systematically controlling the pitch (nanopore's center to nanopore's center) from 15 nm to 50 nm, a series of stable graphene nanomesh devices were achieved. This provides a practical way to investigate the intrinsic properties of graphene nanomesh towards the application for gas sensing, phonon engineering, and quantum technology.

Graphene, with its excellent electrical, thermal and optical properties, is promising for many applications in the next decade. It is also a potential candidate instead of silicon to build the next generation of electrical circuits. However, without a bandgap, it is not straightforward to use graphene as field-effect transistors (FETs). Researchers tried to cut the graphene sheet into a small piece of graphene nanoribbon and observed the bandgap opening successfully. However, the current of graphene nanoribbons is too low to drive the integrated circuit. In this case, the graphene nanomesh is pointed out by introducing periodical nanopores on the graphene, which is also considered as very small graphene nanoribbon array.

A research team led by Dr Fayong Liu and Professor Hiroshi MIZUTA has demonstrated in collaboration with researchers at the National Institute of Advanced Industrial Science and Technology (AIST) that large area suspended graphene nanomesh is quickly achievable by the helium ion beam microscopy with sub-10 nm nanopore diameter and well-controlled pitches. Comparing to slow speed TEM patterning, the helium ion beam milling technique overcomes the speed limitation, and meanwhile, provides a high imaging resolution. With the initial electrical measurements, it has found that the thermal activation energy of the graphene nanomesh increased exponentially by increasing the porosity of the graphene nanomesh. This immediately provides a new method for bandgap engineering beyond the conventional nanoribbon method. The team plans to continue exploring graphene nanomesh towards the application of phonon engineering.

"Graphene nanomesh is a kind of new 'brick' for modern micromachine systems. Theoretically, we can generate many kinds of periodical patterns on the original suspended graphene, which tunes the property of the device to the direction for a special application, in particular nanoscale thermal management" says Prof. Hiroshi Mizuta, the Head of MIZUTA Lab. The MIZUTA lab is currently developing the electrical and thermal properties of graphene-based devices for fundamental physics and potential applications such as gas sensors and thermal rectifier. The aim is to use graphene to build a green world.

Tags:  Fayong Liu  Graphene  graphene nanoribbons  Hiroshi MIZUTA  Japan Advanced Institute of Science and Technology 

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Preventing metal pipe corrosion

Posted By Graphene Council, Wednesday, April 22, 2020
A thin, single layer of graphene material only 1 atom thick may reduce metal pipe corrosion rates as much as 100 times, according to Govind Chilkoor, a research scientist at the South Dakota School of Mines & Technology. These new crystalline 2D materials could mean big savings to industries.

Corrosion costs the U.S. water and wastewater industry about $36 billion annually, or 3.1% of the nation’s gross domestic product, according to a 2002 U.S. Federal Highway Administration study. Those annual losses have now risen to an estimated $58.5 billion.

“All the piping and equipment used to treat water and wastewater can be prone to corrosion,” explained Chilkoor. He developed and tested 2D materials as part of his doctoral work at South Dakota Mines under the tutelage of associate civil and environmental engineering professor Venkata Gadhamshetty, who received a National Science Foundation CAREER award to support the 2D materials research for microbial corrosion research.

As part of that project, Chilkoor examined whether 2D materials can reduce the impact of sulfate-reducing bacteria, one of the main culprits responsible for corrosion in the water and wastewater industry. “Steel exposed to chemicals corrodes at a rate of 1.3 milliinch (thousandths of an inch) per year, but in the presence of sulfate-reducing organisms, it will corrode 24 milliinch per year,” he said.

Bacterial buildup and corrosion

As wastewater flows through a metal pipe, sulfate-reducing bacteria begin colonizing the interior surface and form a slimy film within 10 days. The bacteria excrete a sticky polymer substance and, as the microorganisms accumulate, form a biofilm. “If you put a biofilm under a scanning electron microscope, you will see lots of live bacteria,” he explained.

The sulfate-reducing bacteria corrode the metal in several ways, Chilkoor said. First, the bacteria pull electrons from the steel surface. Second, the bacteria consume organic matter in the wastewater, producing hydrogen sulfide that then erodes both cast iron and stainless steel.

Applying polymer coatings to reduce corrosion has had limited success. The thin plastic coatings are prone to biodegradation. “The microbes get into small pores in the coating and consume the plasticizer in the polymer,” Chilkoor explained.

Polymer coatings can also become brittle, crack and peel, which then releases toxins from pigments and organic compounds in the polymer into the water. “This can be a problem for humans and aquatic life,” he noted.

Furthermore, for applications such as heat exchangers designed to cool a hot liquid, the polymer coatings can disrupt functionality, Chilkoor pointed out.

Developing 2D materials

“With 2D materials, we can make thin coatings, less than 1 nanometer thick,” he explained. When Chilkoor applied 2D graphene to metal and exposed it to sulfate-reducing bacteria in what is known as a corrosion cell, the microbes did not attach to the surface.

“Graphene can be very antimicrobial. It can induce oxidative stress and the bacteria will die,” he said. In addition, graphene is highly conductive and will have good heat transfer in a heat exchanger.

“What’s exciting about 2D graphene is the thinner it gets, the stronger it is,” he said. “One single sheet is very strong, in terms of tensile properties and Young’s modulus.”

While polymer coatings use a filler to enhance strength and reduce porosity, 2D materials can use 1 to 2% as much material and get the same properties as a polymer with 60% filler, Chilkoor explained.

In addition, he developed a 2D material using hexagonal boron nitride. Known as white graphene, its properties are similar to graphene, Chilkoor explained. “A single layer of boron protects metal, but it is electrically insulating.”

Chilkoor and Gadhamshetty are continuing their work through the state’s newest research center, 2D-materials for Biofilm Science and Engineering Centerr, or 2DBEST, which seeks to build nanocoatings for corrosion prevention and agricultural and other applications. Gadhamshetty is one of the center’s lead researchers working on 2D materials and metal corrosion.

The research center is funded through a five-year, $20 million National Science Foundation Research Infrastructure Improvement Track-1 grant awarded to the South Dakota Established Program to Stimulate Competitive Research and the South Dakota Board of Regents. Faculty from 11 South Dakota universities and colleges are involved in the center, including eight South Dakota State University researchers who will use 2D graphene to improve the ability of nitrogen-fixing bacteria to colonize soybean roots.

Currently, the corrosion group is using chemical deposition equipment, which accommodates only small metal pieces, to synthesize the 2D materials, Chilkoor said. To bring 2D materials to a commercial market, “we need to coat a whole pipeline.”

Gadhamshetty said,“ The goal of the 2DBEST is not only to be on the cutting edge with respect to 2D materials synthesis equipment and expertise, but equally significant is to use this research to understand and cater to the unique needs of agriculture, biotechnology and coating industry and small scale businesses in South Dakota and beyond.”

As part of 2DBEST’s infrastructure-building efforts, the researchers will purchase new chemical vapor deposition and pulsed laser deposition equipment that will help move 2D materials toward commercialization.

Tags:  2D materials  coatings  Corrosion  Govind Chilkoor  Graphene  South Dakota School of Mines and Technology  Venkata Gadhamshetty 

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Grolltex Joins Fight Against Pandemic

Posted By Graphene Council, Monday, April 20, 2020
As researchers and companies around the world set out to battle the Coronavirus pandemic, many are revisiting graphene as a material with potential for helping to win this fight.

Grolltex Inc., a San Diego area biosensor startup that manufactures graphene has partnered up with Sanford Burnham Prebys Medical Discovery Institute to develop a virus testing platform to help combat COVID-19.

The project involves using hand held reader units and disposable plastic testing chips designed for U.S. points of entry including, hospitals and “point of care” locations.

Jumping on the Project
Founded in 2017, Jeff Draa, co-founder and CEO of Grolltex said, “When we saw the COVID-19 virus detection work come out in the literature, showing sensitive and selective detection with a graphene sensor, we knew we had to jump on this project.”

Earlier this month, a team led by Boston College researchers used a sheet of graphene to track the electronic signals inherent in biological structures, to develop a platform to selectively identify deadly strains of bacteria.

Most interestingly, graphene sensors have been shown for several years to be capable of advanced detection and testing in fields such as genomics, small molecule-protein receptor interactions and advanced allergen sensing as well as virus detection, including Zika.

Graphene–Based Sensor
The new scientific findings also show a robust capability for a graphene-based sensor to detect the COVID-19 virus.

“Productization and roll out of a sensor like this is right in our technology wheelhouse. We’re very thankful for the quick response of the folks at Sanford Burnham with their help on the science and testing. It would take many more months, maybe even years, without them,” Draa said.

The company which spun out of UC San Diego has raised a total of $2.2 million from Tech Coast Angels, UC San Diego’s Triton Technology Fund, among other local investors.

Over the past three years, Grolltex primarily sold raw research materials to labs across the globe and eventually pivoted to servicing biosensors giants including a publicly-traded pharmaceutical company and another pharmaceutical organization based in Japan. Names were not disclosed.

As for the project, the “graphene sensor chip on plastic” platform uses a very small biological sample and can perform up to 4 to 12 viral tests, all at one time. As a result, this information may indicate the presence of having a normal flu symptoms versus serious pathogens, including the novel coronavirus.

In addition, its technology is plumbed with a number of control channels which eliminates time-consuming verification steps and helping to provide answers in minutes.

Can Be Made for Pennies
In terms of cost, using the Grolltex industrial-scale graphene manufacturing platform, sensing chips can be made for pennies and in arrays of about 10,000 per single square foot sheet, 100 sheets at a time, according to the company.

In particular, the sensor employs monolayer graphene, a single atom thick layer material. On top of the graphene, the company places additional proprietary and patented nanotechnology, including a unique sensing capability made of “gold nano-islands.”

As of today, the small startup lacks the bandwidth to roll its virus detection platform out following the completion of the science. Draa said, what lies ahead for the startup is to find a local financial partner to help scale its testing platform.

“We currently have our hands full with several prototyping efforts in place in other areas, ranging from glucose detection in saliva to a wearable blood pressure monitor in a patch configuration. But when the Sanford Burnham folks volunteered the science help on this COVID virus detection platform, we knew we had to jump on it”, said Draa, “We’re still a small start-up so we’re looking for a financial or resource partner to help us get this up to volume and in the right hands. We know we’re in one of the best locations in the U.S. for an effort like this so once we make the partnering connections, the ramp will be fast.”

Tags:  Boston College  Graphene  Groltex  Healthcare  Jeff Draa  Sensors 

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Pushing the Limits of 2D Supramolecules

Posted By Graphene Council, Saturday, April 18, 2020
Scientists at the University of South Florida have reached a new milestone in the development of two-dimensional supramolecules – the building blocks that make areas of nanotechnology and nanomaterial advancement possible.

Since the 2004 discovery of graphene, the world’s thinnest (one atom thick) and strongest (200 times stronger than steel) material, researchers have been working to further develop similar nanomaterials for industrial, pharmaceutical and other commercial uses. Thanks to its conductive properties and strength, graphene can be used in microelectronics to fortify mechanical materials and has recently enabled precise 3D imaging of nanoparticles.

 While work to develop new supramolecules capable of further applications has seen some success, those molecular formations are either small – less than 10 nanometers in size – or arbitrarily assemble, limiting their potential use. But now, new research published in "Nature Chemistry," outlines a profound leap forward in supramolecular progress.

“Our research team has been able to overcome one of the major supramolecular obstacles, developing a well-defined supramolecular structure that pushes the 20-nanometer scale,” said Xiaopeng Li, an associate professor in the USF Department of Chemistry and the study’s lead researcher. “It’s essentially a world record for this area of chemistry.”

Li, along with his USF research team, collaborated with Saw Wai Hia’s team at the Argonne National Laboratory and Ohio University, as well as several other U.S. and international research institutes on this effort.

Supramolecules are large molecular structures made up of individual molecules. Unlike traditional chemistry, which focuses on covalent bonds between atoms, supramolecular chemistry studies the noncovalent interactions between molecules themselves. Many times, these interactions lead to molecular self-assembly, naturally forming complex structures capable of performing a variety of functions.

In this latest study, the team was able to build a 20-nm-wide metallo-supramolecular hexagonal grid by combining intra- and intermolecular self-assembly processes. Li says the success of this work will advance further understanding of the design principles governing these molecular formations and could one day lead to the development of new materials with yet-to-be-discovered functions and properties.

Tags:  Argonne National Laboratory  Graphene  nanomaterial  nanoparticles  Ohio University  University of South Florida  Xiaopeng Li 

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