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)
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.
For further information, please contact:Margarete Lehné
Monika Landgraf | EurekAlert!
22.02.2018 | Albert-Ludwigs-Universität Freiburg im Breisgau
Separate brain systems cooperate during learning, study finds
22.02.2018 | Brown University
Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.
But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...
Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.
The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
22.02.2018 | Life Sciences
22.02.2018 | Physics and Astronomy
22.02.2018 | Earth Sciences