Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Nanoscaled Tip Writes Artificial Cell Membranes

15.10.2013
Biomimetic Membranes on Graphene Open up Novel Applications in Biotechnology – Publication in “Nature Communications“

Researchers around Dr. Michael Hirtz from Karlsruhe Institute of Technology and Dr. Aravind Vijayaraghavan from the University of Manchester have developed a new method to produce artificial membranes:


By means of lipid dip-pen nanolithography (L-DPN), lipid membranes are written directly onto the two-dimensional carbon graphene. (Graphics: Hirtz/Nature Communications)

Using a nanoscaled tip, they write tailored patches of phospholipid membrane onto a graphene substrate. The resulting biomimetic membranes, i.e. membranes simulating biological structures, allow for the specific investigation of functions of cell membranes and the development of novel applications in medicine and biotechnology, such as biosensors. The method is now presented online in “Nature Communications”.

Lipids (from Greek lipos, “fat”) are central structural elements of cell membranes. The human body contains about 100 trillion cells, each of which is enveloped in a cell membrane which essentially is a double layer of partly hydrophilic, partly hydrophobic phosphorus-containing lipids. These cell membranes contain numerous proteins, ion channels, and other biomolecules, each performing vital functions. It is therefore important to study cell membranes for many areas of medicine and biotechnology. Better understanding of their functions will open up novel applications, such as sensors with biological components, use of enzymes as catalysts, or specific introduction of medical substances. However, it is very difficult to study the membranes directly in live cells inside the human body.

Consequently, researchers frequently use model membranes that are applied to special surfaces. These biomimetic systems, i.e. systems simulating biological structures, are more convenient and can be controlled much better. An international group of researchers around Dr. Michael Hirtz, head of the project in the research unit of Professor Harald Fuchs at the KIT Institute of Nanotechnology (INT), and Dr. Aravind Vijayaraghavan from the University of Manchester, Great Britain, now presents a new method to produce biomimetic membranes: They write tailored patches of phospholipid membrane onto a graphene substrate by means of lipid dip-pen nanolithography (L-DPN), a method developed at KIT.

“The L-DPN technique uses a very sharp tip to write lipid membranes onto surfaces in a way similar to what a quill pen does with ink on paper,” explains Dr. Michael Hirtz from the INT. This tip has an apex in the range of a few nanometers only and is controlled with a high precision by a machine. In this way, minute structures can be produced, smaller than cells and even down to the nanoscale (1 nanometer corresponds to 10-9 meters). By employing parallel arrays of these tips, different mixtures of lipids can be written in parallel, allowing for patterns of variable chemical composition with a size smaller than that of an individual cell.

The graphene that is used as a substrate is a semi-metal with unique electronic properties. According to Dr. Aravin Vijayaraghavan from the University of Manchester, the lipids applied onto graphene spread uniformly, thus forming high-quality membranes. Other advantages of graphene are its tunable conductivity and its property to quench fluorescence of labeled phospholipids. When the lipids contain the corresponding binding sites, such as biotin, the membranes actively bind streptavidin, a protein produced by certain bacteria and used in various biotechnological methods. When the lipids are charged, charge is transferred from the lipids into graphene. This changes the conductivity of graphene, which may be used as a detection signal in biosensors.

The researchers around Hirtz will use their biomimetic membranes in the future to construct novel biosensors based on graphene and lipids. It is planned to design sensors that react to the binding of proteins by a change of conductivity as well as sensors detecting the function of ion channels in membranes. Ion channels are pore-forming proteins via which electrically charged particles can cross the membrane. “Protein sensors might be applied in medical diagnostics. Controlling the function of ion channels is important in drug research,” the KIT scientist says.

M. Hirtz, A. Oikonomou, T. Georgiou, H. Fuchs, & A. Vijayaraghavan: Multiplexed biomimetic lipid membranes on graphene by dip-pen nanolithography. Nature Communications,
10 Oct 2013 | DOI: 10.1038/ncomms3591.

Karlsruhe Institute of Technology (KIT) is a public corporation according to the legislation of the state of Baden-Württemberg. It fulfills the mission of a university and the mission of a national research center of the Helmholtz Association. Research activities focus on energy, the natural and built environment as well as on society and technology and cover the whole range extending from fundamental aspects to application. With about 9000 employees, including nearly 6000 staff members in the science and education sector, and 24000 students, KIT is one of the biggest research and education institutions in Europe. Work of KIT is based on the knowledge triangle of research, teaching, and innovation.

or, 10.10.2013

For further information, please contact:

Margarete Lehné
Presse, Kommunikation und Marketing
Phone: +49 721 608-48121
Fax: +49 721 608-45681
margarete lehne∂kit edu

Monika Landgraf | EurekAlert!
Further information:
http://www.kit.edu

More articles from Life Sciences:

nachricht Cancer diagnosis: no more needles?
25.05.2018 | Christian-Albrechts-Universität zu Kiel

nachricht Less is more? Gene switch for healthy aging found
25.05.2018 | Leibniz-Institut für Alternsforschung - Fritz-Lipmann-Institut e.V. (FLI)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Powerful IT security for the car of the future – research alliance develops new approaches

The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.

Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

12th COMPAMED Spring Convention: Innovative manufacturing processes of modern implants

28.05.2018 | Event News

In focus: Climate adapted plants

25.05.2018 | Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

 
Latest News

International Workshop Sees Central Role for Solar in Transforming the World Energy Economy

28.05.2018 | Seminars Workshops

Cognitive Power Electronics 4.0 is gaining momentum

28.05.2018 | Trade Fair News

Organic light-emitting diodes become brighter and more durable

28.05.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>