Graphene joins forces with gold to enable improved neural probes

Apr 20, 2017

Researchers from the Daegu Gyeongbuk Institute of Science & Technology in Korea have used graphene to develop neural probes that are small, flexible and read brain signals clearly.

The probe consists of an electrode, which records the brain signal. The signal travels down an interconnection line to a connector, which transfers the signal to machines measuring and analyzing the signals. The electrode starts with a thin gold base. Attached to the base are tiny zinc oxide nanowires, which are coated in a thin layer of gold, and then a layer of conducting polymer called PEDOT. These combined materials increase the probe's effective surface area, conducting properties, and strength of the electrode, while still maintaining flexibility and compatibility with soft tissue.

Graphene-based transistors show promise for optical technologies

Apr 18, 2017

Researchers at Purdue University, the University of Michigan and Pennsylvania State University have combined graphene with a (comparatively much larger) silicon carbide substrate, creating graphene field-effect transistors which can be activated by light. This may lead to the development of highly sensitive graphene-based optical devices, an advance that could bring applications from imaging and displays to sensors and high-speed communications.

GFETs show promise for optical technologies image

A typical problem of graphene-based photodetectors is that they have only a small area that is sensitive to light, limiting their performance. “In typical graphene-based photodetectors demonstrated so far, the photoresponse only comes from specific locations near graphene over an area much smaller than the device size,” the team said. “However, for many optoelectronic device applications, it is desirable to obtain photoresponse and positional sensitivity over a much larger area”. The researchers tackled exactly this in their new work.

Graphene may assist in producing cells vital for nerve regeneration

Apr 11, 2017

Researchers at Iowa State University (ISU) are developing a graphene-based method to transform stem cells into Schwann-like cells (cells of great importance for various nerve regeneration efforts). If successful, this process has potential to replace the complicated and expensive process used today.

Graphene helps regenerate nerves image

The team's method uses inkjet printers to print multi-layer graphene circuits and also uses lasers to treat and improve the surface structure and conductivity of those circuits. It turns out that mesenchymal stem cells adhere and grow well on the treated circuit’s rough 3D nanostructures. With the addition of small doses of electricity – 100 millivolts for 10 minutes per day over 15 days – the stem cells become Schwann-like cells.

Researchers from India use mango leaves to make fluorescent graphene quantum dots

Apr 09, 2017

Researchers from the Indian Institute of Technology (IIT) have used mango leaves to synthesize fluorescent graphene quantum dots, and integrated those into probes for bioimaging and intracellular temperature sensing.

The unique quantum dots are reportedly biocompatible, have excellent photostability and show no cellular toxicity. To make them, the team cut mango leaves and froze them using liquid nitrogen. The frozen leaves were crushed into powder and dipped in alcohol. The extract was centrifuged and the supernatant evaporated in an evaporator and then heated in a microwave for five minutes to get a fine powder.

Updates from Prof. James Tour's graphene lab at Rice University

Apr 09, 2017

Prof. James Tour's research lab in Rice University is one of the leading graphene research groups in the world, with several key technologies first discovered and developed there. Professor Tour is involved with several application areas - from de-icing coating to energy storage and quantum dots production. Prof. Tour was kind enough to share his time and update us on the latest research and commercialization efforts at his lab.

rice university laser process supercapacitor image

The Tour group is now commercializing two of its key technologies. First up is the laser-induced graphene (or LiG), which was reported first in 2014. This is a process in which graphene is formed on a flexible polyimide film using a room-temperature laser-based process. It is possible to pattern this graphene to create devices and as it is formed on a flexible film this easily enables flexible electronics applications.