Polymer membranes for the incorporation of nanopores

In the framework of the interdisciplinary cluster Nanodiag, the Polymer Physics group will investigate and optimize model membranes built from block copolymers or lipo-polymers for an innovative nanopore technology. 

Biological nanopores can be produced from pore-forming proteins which insert into a lipid membrane and organise themselves to create a nanometre-sized channel across the membrane. These nanopores allow transport of ions and (bio)-molecules through the membrane. In biological systems, such nanopore channels regulate the transport of ions and molecules in and out of cells.

Embedded in the electrically insulating membrane, which is suspended in aqueous solution, such a nanopore can be employed as a single molecule detector which even can discriminate between different species. When voltage is applied across such a detector-membrane, a current of ions flows through the pore. The lengths and diameters of biological pores are commensurate with molecular dimensions and therefore the ionic current is blocked when a molecule is translocating through the pore. Both the duration of the blockade and the value of the residual current provide information about the interaction between the translocating species and the pore and can therefore be used to identify individual molecules.

Currently, this principle is commercial applied only for the detection and sequencing of DNA and RNA. However, in order to widen the potential application range, for example, to the identification of proteins, this technology requires further development.

The Polymer Physics group in Freiburg has a long-standing expertise in preparation, visualisation and analysis of properties and molecular structures of ultrathin polymer films, in particular by means of atomic force microscopy at the nanometre scale. In this project monolayers of surface-active molecules will be prepared at the water surface of a Langmuir trough. Properties of these monolayers can be adjusted by controlling the surface density of the interfacial molecules, possibly introducing a series of phase transitions.  The variability and versatility of their properties qualify these monolayers as promising candidates for model membranes, also with respect to biological applications.

In this context, we are looking for a highly motivated PhD student who has a master degree in physics, chemistry, nanoscience or another related field. Experimental skills and a solid background in physics or chemistry of macromolecules are required. However, even more important is the capability to work in a multidisciplinary research team and to acquire all relevant competencies which are needed to solve underlying physical and chemical problems related to achieving suitable membrane systems for an innovative nanopore technology.

We offer an exciting field of multidisciplinary research of societal relevance, advanced and unique experimental tools as well as intensive supervision, embedded in a dynamic international team. The Experimental Polymer Physics group provides its infrastructure and know-how for the work on the PhD project.

The position is limited to 3 years. The salary will be determined in accordance with E13 TV-L.
For the position advertised here, we particularly encourage applications from women.

For further information, please contact Dr. Renate Reiter at +49 761 203 97782 or by e-mail: renate.reiter@physik.uni-freiburg.de.