Biology - Page 4

The University of Manchester announced that world-leading nanomedicine expert, Professor Kostas Kostarelos will join the University in June. Kostas is already collaborating with Manchester's Professor Andre Geim and Professor Kostya Novoselov on graphene-based products for medicine applications. Kostas is focused on targeted drug delivery.

Professor Kostarelos is also researching nano-technology treatment for cancer.

According to Reuters, researchers from the University College London is researching graphene nanomaterials for medicine applications, and is already in pre-clinical experiments. Unfortunately we do not have more information about this specific research,

Researchers from MIT use DNA to form nanoscsale shapes on graphene. The idea is to fold DNA to a specific shape and then deposit it on graphene. Using plasma lithography the shapes are then "etched" to the graphene sheet.

The researchers created the DNA structures using short synthetic DNA strands called single-stranded tiles. The tiles are assembled into shapes in a simple reaction. They can also be constructed using an approach called DNA origami, in which many short strands of DNA fold a long strand into a desired shape.

A couple of weeks ago we reported about China's Zhejiang University's new sponge-like solid material (which they call Graphene Aerogel) made from freeze-dried carbon and graphene oxide. Now it seems that these foams may be used as conductive scaffolds for neural stem cells (NSCs).

Korean researchers already discovered that graphene sheets is better than glass for human neural stem cells growth - exhibiting a greater ratio of neurons to glial cells. Now Chinese researchers say that graphene foams coated with laminin (or other matrix proteins) could potentially serve not only as compatible neural housing but also as a means to control the tenants electrically.

Back in January we reported about Duke University's study into crumpling and unfolding of large area graphene. This enables all sorts of applications, including artificial muscles. AzoNano posted an interesting interview with Duke's Assistant Professor Xuanhe Zhao.

Xuanhe says that crumbled graphene electrodes have a number of advantages - such as lightweight, high transparency, and superhydrophobicity. The team still needs to achieve a systematic understanding of the crumpling and unfolding of graphene, and they also need to develop a way to fabricate such devices for large-scale production.

Researchers from China's National Tsing Hua University found a new use for graphene: photothermal antibacterial therapy. The researchers say that during experiments both gram-positive Staphylococcus aureus and gram-negative Escherichia coli were efficiently captured by glutaraldehyde and concentrated (or immobilized) by the magnetic property of a magnetic reduced graphene oxide functionalized with glutaraldehyde.

The bacteria were rapidly killed by multiple means, including conventional oxidative stress as well as physical piercing and photothermal heating of graphene by near-infrared (NIR) laser irradiation.

Neural prostheses are exciting researchers, but silicon based devices are difficult to integrate with soft tissue. Now researchers from the Technische Universität München in Germany are experimenting with graphene based neural prostheses, saying that graphene has excellent biocompatibility.

The researchers have shown that it's possible to make graphene based transistors that are gated by the solution in which the transistor sits. In other words, the natural body fluids that surround these prostheses will form an integral part of their operation. Those "solution-gated transistors" far outperform other technologies.

Update: read more about Duke's graphene-based artifical muscles research here

Researchers from Duke University are developing ways to control the crumpling and unfolding of large area graphene. By attaching the graphene to a pre-stretched rubber film. When the film was relaxed, parts of the graphene sheet detached, forming an attached-detached pattern with a feature size of a few nanometers. When the film was stretched again, the adhered spots of graphene pulled on the crumpled areas to unfold the sheet.

So basically stretching and relaxing a rubber film, even manually can crumple and unfold large area graphene sheets. This opens up the possibility of all sorts of applications. One example is a graphene film that can be changed from transparent to opaque (it is transparent when stretched but opaque when crumpled).

Researchers from the University of Manchester and Aix-Marseille University developed a new optical device that can analyze a single molecule quickly, using Plasmonics (the study of vibrations of electrons in different materials). This could lead to virus detectors, fast and accurate athlete drug testing and explosive tracking in airports.

The device uses artificial materials with topological darkness that are highly sensitive to a single small molecule (this relies on topological properties of light phase). The artificial material is covered with graphene (which they say is one of the best materials that can be used to measure the sensitivity of molecules). Basically the device is like a single-molecule microscope.

Researchers from MIT and the Oak Ridge national Laboratory (ORNL) developed a promising new graphene-based membrane that can be useful to filter microscopic contaminants from water or for drug delivery. The membrane features high flux and tunability (i.e. it can quickly filter fluids but also be easily tunable to let certain molecules through while stopping others).

To develop the membrane, the team fabricated a 25 square millimeter graphene sheet using CVD. They managed to transfer the sheet to a polycarbonate substrate dotted with holes. They thought that the graphene will be totally impermeable, but experiments proved that salts can flow through the membrane.