It’s Not Teleportation You Say: No It Is Diamagnetism: And What Exactly Is That: That Moves Graphite Particles in Liquid Using Magnetism

 

 

 

|| February 22: 2019: UCL News || ά. A way of transporting tiny particles of graphite in liquid, using magnetic fields, has been developed by UCL scientists. It opens up possibilities for new ways of precisely transporting specific components in fluids, including, in bio-compatible fluids, such as, in the human body. The findings, published in Proceedings of the National Academy of Sciences, could have implications for improved chemical detection, non-invasive healthcare diagnosis and drug delivery via miniaturised devices or via small-scale robotic tools.

Transporting micro-particles, which are the size of a tenth of a human hair, in liquid, is difficult, due to the strong drag forces, which are comparable to those at play when moving a macro-particle through dense honey. The new method used a weak type of magnetism, called, diamagnetism, to control the position of bio-compatible graphite micro-flakes in liquid. Diamagnetism had been used before, for instance, to levitate living frogs with very strong magnets but, the diamagnetism of micro-graphite had never been exploited for controlled motion in aqueous fluids before now.

The graphite flakes are a similar size or smaller than human cells and could be used to carry large molecules in a variety of scenarios. This replaces the need for costly micro-fluidic pumps, enabling simpler, cheaper and more reliable tools and sensing applications. Moreover, graphite is composed solely of carbon, which is the key and most abundant component of all organic matter. This allows for the bio-compatible use of graphite micro-particles to control organic or biological reactions without the addition of contaminants, such as, typical magnetic materials.

‘’Our discovery is really exciting for the field because we’ve demonstrated contactless controlled magnetic transport of micro-graphite in a completely bio-compatible medium.” said the Lead Author Dr Isabel Llorente-Garcia, UCL Physics and Astronomy.

“The challenge was similar to moving tennis balls through honey without being able to touch them directly. Our work opens the door to a range of new possibilities for exploiting the fascinating properties of micro-graphite for remote non-invasive manipulation applications in bio-sensing, drug delivery, bio-physics and soft-electronic experiments.”

It’s well known that ferro-magnetic materials, such as, iron filings, can be manipulated with magnetic fields as they are attracted towards regions of high magnetic field, for example, to magnet poles. In contrast, diamagnetic graphite is repelled by magnetic fields and moves to regions of lowest magnetic field.

This means that diamagnetic particles can be easily controlled at a distance from the magnet and could be confined and moved in three dimensions by applying easy-to-use time-constant magnetic fields. In contrast, ferro-magnetic particles are, typically, attracted towards the magnet and can only be manipulated in three-,  using involved schemes with time-varying magnetic fields.

First Author of the Paper, Dr Johnny Nguyen, UCL Physics and Astronomy, who conducted the magnetic transport experiments with the specially prepared graphite particles, said, “Graphite is a really interesting material. It is the most strongly diamagnetic material known and it has properties, such as, high polarisability and conductivity, broad optical absorption and optically controllable electrical resistance, which allows applications across materials science, physics and chemistry.

The researchers used ultra-sound to break up graphite into micro-particles, each, consisting of a stack of graphite sheets, which were, then, coated in lipid layers to prevent clumping in water. The key to the success of this technique in bio-compatible water solutions was the delicate preparation of the sample. We, also, had to account for complex interactions between the micro-particles and the glass surfaces of the sample container.”

Co-author and PhD candidate Mr Dario V Conca, UCL Physics and Astronomy, who helped characterise the particles, said, “We had to combine expertise in sample preparation with material characterisation via Raman spectroscopy and SQUID measurements to fully understand the properties of the micro-particles we produced, in order to carefully craft configurations of strong magnets to make this work. It really required a diverse team to pull together their knowledge to achieve this outcome.”

Dr Llorente-Garcia’s group is planning to build on this work to demonstrate full three-D trapping of the particles and develop applications for its use. The research was funded by HEFCE, EPSRC and The Leverhulme Trust.

Caption: Fully bio-compatible magnetic transport of a POPC lipid-coated graphite micro-flake in diamagnetic 20mM NaCl aqueous solution: Image: UCL:::ω.

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Can You Find Malaria With This Ogirami LAMP

 

 

|| February 21: 2019: University of Glasgow News || ά. According to researchers, simple folded sheets of waxed paper could help bring affordable, reliable field tests for diseases, such as, Malaria to remote parts of the developing world. In a new Paper, published in the journal Proceedings of the National Academy of Sciences, researchers from universities in Scotland and China, working together with the Ministry of Health in Uganda, describe, for the first time, how origami-style folded paper, prepared with a printer and a hot plate, has helped detect malaria with 98% sensitivity in infected participants from two primary schools in Uganda.

Malaria is one of the world’s leading causes of illness and death, affecting more than 219 million people in 90 countries around the globe and killing 435,000 people in 2017 alone. A significant issue for arresting and reversing the spread of the disease is diagnosing it in people, who are infected but, who do not display any symptoms, a problem, which can only be addressed by widespread field tests. However, current tests, which rely on a process, known as, polymerase chain reaction:PCR, can only be carried out under laboratory conditions, making them unsuitable for use in remote locations.

The research team, led by researchers from the University of Glasgow, in partnership with Shanghai Jiao Tong University and the Ministry of Health in Uganda, have developed a new approach to diagnostics. It uses paper to prepare patient samples for a different type of detection process, known as, loop-mediated isothermal amplification or LAMP, which is more portable and better-suited for use in the field.

The origami platform uses a commercially-available printer to coat the paper in patterns made from water-resistant wax, which is, then, melted on a hotplate, bonding the wax to the paper. A blood sample taken from a patient via finger prick is placed on in a channel in the wax, then, the paper is folded, directing the sample into a narrow channel and, then, three small chambers, which the LAMP machine uses to test the samples’ DNA for evidence of Plasmodium Falciparum, the mosquito-borne parasitic species, which causes Malaria. The test can be completed on-site in less than 50 minutes.

Professor Jonathan Cooper of the University of Glasgow’s School of Engineering is the Paper’s Lead Author. He said, “We tested our approach with volunteers from two primary schools in the Mayuge and Apac districts in Uganda. We took samples from 67 school children, under strict ethical approval and ran diagnostic tests in the field, using optical microscopy techniques, the gold standard method in these low-resource settings, a commercial rapid diagnostic procedure, known as, a lateral flow test and our LAMP approach. We, also, carried out PCR back in Glasgow, on samples collected in the field.

Our diagnostic approach correctly diagnosed Malaria in 98% of the infected samples we tested, markedly more sensitive than both the microscopy and lateral flow tests, which delivered 86% and 83% respectively. It’s a very encouraging result, which suggests that our paper-based LAMP diagnostics could help deliver better, faster, more effective testing for Malaria infections in areas, which are, currently, underserved by available diagnostic techniques."

Dr Julien Reboud of the University of Glasgow’s School of Engineering played a key role in developing the new diagnostic technique. Dr Reboud said, “These are challenging environments for any test of this type, with no access to the kinds of refrigeration, special equipment and training that more traditional diagnostic procedures require, so it’s very encouraging that the diagnostic techniques we’ve developed have proven to be so sensitive and reliable.

With Malaria infections on the increase in 13 affected countries according to a World Health Organisation report released last year, it’s vital that new forms of diagnosis reach the people, who need them, and we’re committed to developing our approach to paper-based LAMP diagnostics further after this encouraging study.”

The research was supported by funding from the UK Global Challenges Research Fund, the Scottish Funding Council, and the Engineering and Physical Sciences Research Council:EPSRC.

The Paper: Microfluidics for Diagnosing Malaria in Low Resource Rural Environments: Published in Proceedings of the National Academy of Sciences:::ω.

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New Study Finds: Nano-particles May Promote Cancer Metastasis

 

 

 

 

|| February 12: 2019: 2019: National University of Singapore News || ά. A new Study findings caution against possible side effects of cancer nano-medicines and other common nano-particles but paves the way for safer design and better treatment strategies. Nano-particles can be found in processed food, e.g, food additives, consumer products, e.g, sunscreen and, even, in medicine. While these tiny particles could have large untapped potential and new applications, they, may, have unintended and harmful side effects, according to this Study by researchers of the University.

Researchers found that cancer nano-medicine, which are designed to kill cancer cells, may, accelerate metastasis. Using breast cancer as a model, they discovered that common nano-particles made from gold, titanium dioxide, silver and silicon dioxide, also, used in nano-medicines, widen the gap between blood vessel cells, making it easier for other cells, such as, cancer cells, to go in and out of ‘leaky’ blood vessels. The phenomenon, named, ‘nano-materials induced endothelial leakiness’:Nano-EL by the researchers, accelerates the movement of cancer cells from the primary tumour and, also, causes circulating cancer cells to escape from blood circulation. This results in faster establishment of a bigger secondary tumour site and initiates new secondary sites previously not accessible to cancer cells.

“For a cancer patient, the direct implication of our findings is that long term, pre-existing exposure to nano-particles, for instance, through everyday products or environmental pollutants, may, accelerate cancer progression, even, when nano-medicine is not administered.” said research Co-leader Associate Professor David Leong from the Department of Chemical and Biomolecular Engineering at NUS Faculty of Engineering.

“The interactions between these tiny nano-materials and the biological systems in the body need to be taken into consideration during the design and development of cancer nano-medicine. It is crucial to ensure that the nano-material delivering the anti-cancer drug does not, also, unintentionally, accelerate tumour progression. As new breakthroughs in nano-medicine unfold, we need to, concurrently, understand what causes these nano-materials to trigger unexpected outcomes.”

Fortunately, the situation is not doom and gloom. The researchers are harnessing the Nano-EL effect to design more effective therapies. For example, nano-particles, that induce Nano-EL can, potentially, be used to increase blood vessel leakiness and, in turn, promote the access of drugs or repairing stem cells to diseased tissues, that, may not, be, originally, accessible to therapy.

Associate Professor Leong said, “We are currently exploring the use of the Nano-EL effect to destroy immature tumours when there are little or no leaky blood vessels to deliver cancer drugs to the tumours. We need to tread this fine line very carefully and optimise the duration, at which, the tumours are exposed to the nano-particles. This could allow scientists to target the source of the disease, before the cancer cells spread and become a highly refractory problem.”

Associate Professor Ho said, “Moving beyond cancer treatment, this phenomenon, may, also, be exploited in other conditions where a failure of leakiness is a key feature. For instance, organ injuries, such as, Liver Fibrosis, may, cause excessive scarring, resulting in a loss in leakiness, which reduces the entry of nutrient supplies via the blood vessels. Both our research groups are now looking into leveraging the Nano-EL effect to restore the intended blood flow across the scarred tissues.”

Caption: When blood vessel cells, left, are treated with a short exposure of titanium dioxide nano-particles for 30 minutes, cell-sized gaps, right began to form. These gaps can be exploited by cancer cells to migrate out of the primary tumour or from blood circulation. Researchers observed this phenomenon for other common nano-particles made from gold, silver and silver dioxide: Image: National University of Singapore:::ω.

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New Research Finds: Graphene Bio-sensor Could Provide Early Lung Cancer Diagnosis

 

 

|| February 05: 2019: University of Exeter News || ά. Graphene could hold the key to unlocking the next generation of advanced, early stage lung cancer diagnosis. A team of scientists from the University of Exeter has developed a new technique, that could create a highly sensitive graphene bio-sensor with the capability to detect molecules of the most common lung cancer bio-markers. The new bio-sensor design could revolutionise existing electronic nose devices, that identify specific components of a specific vapour mixture, for example, a person’s breath and analyses its chemical make-up to identify the cause.

The research team believes that the newly developed device displays the potential to identify specific lung cancer markers at the earliest possible stage, in a convenient and reusable way, making it both cost-effective and highly beneficial for health service providers worldwide. The research is published in the Royal Society of Chemistry’s peer-reviewed journal ‘Nanoscale’. The quest to discover viable new techniques to, accurately, detect early-stage lung cancer is one of the greatest global health care challenges. Although, it is one of the most common and aggressive cancers, killing around 01.4 million people worldwide each year, the lack of clinical symptoms in its early stages, means many patients are not diagnosed until the latter stage, which makes it difficult to cure.

Mr Ben Hogan, a Postgraduate researcher from the University of Exeter and Co-author of the paper said, “The new bio-sensors, which we have developed, show that graphene has significant potential for use as an electrode in e-nose devices. For the first time, we have shown that with suitable patterning graphene can be used as a specific, selective and sensitive detector for biomarkers.

We believe that, with further development of our devices, a cheap, reusable and accurate breath test for early-stage detection of lung cancer can become a reality.’’ Due to the unrestrainable nature of the abnormal cancer cells, while they begin in one or both lungs, they are prone to spread to other parts of the body rapidly.

There are currently no cheap, simple or widely available screening methods for early diagnosis of lung cancer.  However, for the new research, the researchers looked at whether graphene could form the basis for a new, enhanced bio-sensor device.

Using multi-layered graphene with current e-nose devices, which combine electronic sensors with mechanisms for pattern recognition, such as, a neural network, these new devices could revolutionise breath diagnostic techniques. Using patterned multi-layered graphene electrodes, the researchers were able to show greater sensing capabilities for three of the most common lung-cancer bio-markers, ethanol, isopropanol and acetone, across a range of different concentrations.

The researchers believe that this could be the first step towards creating new, improved and cheaper e-nose devices, that could give the earliest possible lung-cancer diagnosis.

The Paper: Multi-layer graphene as a selective detector for future lung cancer biosensing platforms: E. Kovalska, P. Lesongeur. B. T. Hogana  and  A: Published in Nanoscale:::ω.

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Researchers Develop a New Medical Device That Harnesses Magnetic Field to Speed Up Muscle Recovery

|| January 23: 2019: National University of Singapore News || ά. A non-invasive magnetic stimulation ‘tricks’ muscle cells into thinking that they are exercising and amplifies the biological effect to promote muscle regeneration. The journey of muscle rehabilitation can be long and arduous and requires strong perseverance from the patient. Now, researchers from the National University of Singapore are making the recovery process much easier for patients with an ingenious medical device, capable of regenerating muscles in a non-invasive and painless manner. The device, named, MRegen, makes use of specific magnetic field to trigger and amplify the biological effect of exercise, hence, accelerating muscle recovery. 

The earth is cloaked in a protective magnetic field, which is believed to have enabled life to evolve. Its ability to influence human development has prompted scientists and biomedical companies to seek ways to harness magnetic fields for therapeutic purposes. While creating a magnetic field is simple, the ability to generate the appropriate magnetic stimulation, that triggers a positive therapeutic effect is technologically challenging. A team of researchers, led by Associate Professor Alfredo Franco-Obregón, studied the effects of magnetic fields on muscle cells. By coupling two fundamental concepts, firstly, muscle development, that is regulated by energy production and, secondly, energy management, that is extremely sensitive to magnetic fields.

The researchers developed MRegen, which makes use of a unique magnetic field to activate energy production and trigger muscle regeneration. The energy produced via the magnetic stimulation ‘tricks’ muscle cells into thinking that they are exercising, hence, activating them to adapt and improve at an accelerated speed.

Associate Professor Franco-Obregón, at the Department of Surgery at Yong Loo Lin School of Medicine and the Biomedical Institute for Global Health Research and Technology at NUS, said, “The device provides a uniform electromagnetic field to a muscle area at a magnitude and pulse duration, that reproduces the same regenerative, energetic and metabolic responses as physical activity.

The duration of use for the device has been optimised for providing the largest therapeutic effect in terms of muscle equality, function and metabolic stability. The device is, especially, useful in reducing muscle degradation in periods when physical activity is not possible.”

MRegen has shown promising results in two human trials, conducted between 2015 and 2017. The first human trial examined the effects of MRegen on healthy individuals by giving 10 recruited healthy persons the magnetic field treatment in either their left or right leg. The researchers found that those, who received 10 minutes of magnetic stimulation by MRegen once a week for five consecutive weeks showed an average of 30 to 40 per cent improvement in muscle strength, in both legs. 

The second human trial examined the effectiveness of MRegen in accelerating the muscle recovery of patients, who had undergone anterior cruciate ligament:ACL knee surgery at a local hospital. In this trial, 10 recruited patients were given the normal rehabilitation therapy while 10 other patients were given the magnetic field treatment with MRegen in addition to the rehabilitation therapy. It was observed that the patients, who were treated with MRegen experienced a recovery in muscle size and strength in their operated leg four weeks earlier than those, who had undergone, only, the normal rehabilitation procedures. Most notably, Magnetic Resonance Imaging measurements showed that muscle metabolism, one of the strongest indicators of muscle health and regenerative capacity, improved by up to 50 percent in the patients, who had undergone MRegen’s magnetic field treatment.

Field treatment in one leg has, also, consistently appeared to have positively influenced the health of the other leg in both trials, demonstrating what is known as a contralateral effect. Such an effect has been described in the sports science field but not as strongly observed as with MRegen’s magnetic field therapy. Furthermore, those, who received the magnetic field treatment showed no sign of discomfort or adverse consequences, proving the treatment to be a painless procedure. This breakthrough medical device could, therefore, shift the paradigm of current muscle rehabilitation routine and make the road to recovery shorter and more comfortable for patients.

The researchers filed a patent for this new technology and have since spun off a company, QuantumTX, to commercialise it. They believe that the technology holds great promise for slowing muscle loss and maintaining healthy muscle metabolism in the frail and elderly, as well as, helping to maintain muscle mass for professional athletes during detraining. The NUS team is, also, looking into applying the same technology for treating other health conditions, such as, obesity and diabetes and early stages of their research have already shown encouraging results.

“Muscle makes up 40 per cent of an average person’s body mass and plays a major role in regulating one’s body, health and longevity. If, we can harness the ability to regulate muscle development, we, may, gain greater control of the overall human health. MRegen, which has proven to be non-invasive and effective in regenerating muscles, can be easily modified to treat other human diseases. We foresee this technology playing an important role in disease treatment in the future.” said Mr Franco-Obregón.

Caption: A team of the University researchers, led by Associate Professor Alfredo Franco-Obregón, left, developed MRegen, a medical device capable of regenerating muscles in a non-invasive and painless manner using magnetic field: Image: National University of Singapore:::ω.

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