Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists print sensors on gummi candy: creating microelectrode arrays on soft materials

21.06.2018

Microelectrodes can be used for direct measurement of electrical signals in the brain or heart. These applications require soft materials, however. With existing methods, attaching electrodes to such materials poses significant challenges. A team at the Technical University of Munich (TUM) has now succeeded in printing electrodes directly onto several soft substrates.

Researchers from TUM and Forschungszentrum Jülich have successfully teamed up to perform inkjet printing onto a gummy bear. This might initially sound like scientists at play – but it may in fact point the way forward to major changes in medical diagnostics.


Microelectrode arrays on gelatin: A team surrounding Bernhard Wolfrum, Professor of Neuroelectronics at the Technical University of Munich, has successfully printed sensors on gummi candy.

Nouran Adly / TUM

For one thing, it was not an image or logo that Prof. Bernhard Wolfrum's team deposited on the chewy candy, but rather a microelectrode array. These components, comprised of a large number of electrodes, can detect voltage changes resulting from activity in neurons or muscle cells, for example.

Second, gummy bears have a property that is important when using microelectrode arrays in living cells: they are soft. Microelectrode arrays have been around for a long time. In their original form, they consist of hard materials such as silicon.

This results in several disadvantages when they come into contact with living cells. In the laboratory, their hardness affects the shape and organization of the cells, for example. And inside the body, the hard materials can trigger inflammation or the loss of organ functionalities.

Rapid prototyping with inkjet printers

When electrode arrays are placed on soft materials, these problems are avoided. This has sparked intensive research into these solutions. Until now, most initiatives have used traditional methods, which are time-consuming and require access to expensive specialized laboratories. "If you instead print the electrodes, you can produce a prototype relatively quickly and cheaply. The same applies if you need to rework it," says Bernhard Wolfrum, Professor of Neuroelectronics at TUM. "Rapid prototyping of this kind enables us to work in entirely new ways."

Wolfrum and his team work with a high-tech version of an inkjet printer. The electrodes themselves are printed with carbon-based ink. To prevent the sensors from picking up stray signals, a neutral protective layer is then added to the carbon paths.

Materials for various applications

The researchers tested the process on various substrates, including PDMS (polydimethylsiloxane) – a soft form of silicon – agarose – a substance commonly used in biology experiments – and finally various forms of gelatin, including a gummy bear that was first melted and then allowed to harden. Each of these materials has properties suitable for certain applications. For example, gelatin-coated implants can reduce unwanted reactions in living tissue.

Through experiments with cell cultures, the team was able to confirm that the sensors provide reliable measurements. With an average width of 30 micrometers, they also permit measurements on a single cell or just a few cells. This is difficult to achieve with established printing methods.

"The difficulty is in fine-tuning all of the components – both the technical set-up of the printer and the composition of the ink," says Nouran Adly, the first author of the study. "In the case of PDMS, for example, we had to use a pre-treatment we developed just to get the ink to adhere to the surface."

Wide range of potential applications

Printed microelectrode arrays on soft materials could be used in many different areas. They are suitable not only for rapid prototyping in research, but could also change the way patients are treated. "In the future, similar soft structures could be used to monitor nerve or heart functions in the body, for example, or even serve as a pacemaker," says Prof. Wolfrum. At present he is working with his team to print more complex three-dimensional microelectrode arrays. They are also studying printable sensors that react selectively to chemical substances, and not only to voltage fluctuations.

Publication:

N. Adly, S. Weidlich, S. Seyock, F. Brings, A.Yakushenko, A. Offenhäusser, B. Wolfrum. “Printed Microelectrode Arrays on Soft Materials: From PDMS to Hydrogels.” Npj Flexible Electronics 2:1 (2018). DOI:10.1038/s41528-018-0027-z.

More information:

Prof. Wolfrum’s lab is part of the Munich School of BioEngineering (MSB). This interdisciplinary TUM research center is Europe’s most multi-disciplinary university institution focused on the interface between medicine, engineering and natural sciences.

Munich School of BioEngineering: https://www.bioengineering.tum.de/
Neuroelectronics Group: http://www.nel.ei.tum.de/

High resolution images:

https://mediatum.ub.tum.de/1446441

Contact:

Prof. Dr. Bernhard Wolfrum
Professor of Neuroelectronics
Munich School of BioEngineering
Department of Electrical and Computer Engineering
Technical University of Munich (TUM)
Tel.: +49 (89) 289 – 10887
bernhard.wolfrum@tum.de

Dr. Ulrich Marsch | Technische Universität München

More articles from Power and Electrical Engineering:

nachricht Nano-scale process may speed arrival of cheaper hi-tech products
09.11.2018 | University of Edinburgh

nachricht Nuclear fusion: wrestling with burning questions on the control of 'burning plasmas'
25.10.2018 | Lehigh University

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Purdue cancer identity technology makes it easier to find a tumor's 'address'

16.11.2018 | Health and Medicine

Good preparation is half the digestion

16.11.2018 | Life Sciences

Microscope measures muscle weakness

16.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>