Research
Design and synthesis of digital polymers
It has been shown in recent years that information can be stored at the molecular level in synthetic polymers. To achieve such a property, different comonomers are used as a molecular alphabet and assembled together into a defined information sequence. For instance, an alphabet based on two different monomers allows writing of binary information in a linear polymer chain. But, of course, such informational polymers cannot be synthesized using a standard chain-growth or step-growth polymerization mechanisms because these approaches lead to polydisperse samples containing pronounced sequence defects. Instead, so-called multi-step growth strategies have to be employed. One of the main research topics of the LCIM is to develop fast and facile strategies for the synthesis of digital polymers. In addition, our group investigates innovative molecular design for tuning the informational properties (e.g. readability, erasability storage lifetime) of such polymers.
Spatial organization of informational polymers
A crucial challenge in the field of macromolecular data storage is undoubtedly the spatial organization of digital polymer libraries. In the bulk, digital polymers contain a very large number of uniform chains having all the same sequence-encoded message. However, data storage requires the development of organized polymer libraries, in which a piece of information can be stored in a defined region of space. For nucleic acids, commercial DNA microchips are readily available. Indeed, modern materials science offers many other opportunities to organize soft matter at the nanoscale. For instance, the 2D or 3D organization of digital polymer libraries could be attained via surface patterning, directed self-assembly, co-crystallization, layer-by-layer (LbL) deposition, or by a combination of some of these approaches. The LCIM investigates most of these approaches for preparing basic prototypes of polymer-based data-storage devices.
Informational polymers for identification technologies
Synthetic informational macromolecules also show promise for applications in the areas of product identification, plastics recycling, steganography and anti-counterfeiting technologies. In the latter case, a coded monomer alphabet is used to write an identification sequence in a single polymer chain. Depending on chain-length and on the number of coded symbols used, a certain number of coded combinations is available, thus potentially offering a high level of protection. Such macromolecular taggants can be dispersed in trace amounts in solid, gel or liquid materials. Afterwards, they can be extracted from the host material and decoded using tandem mass spectrometry or other sequencing techniques. Over the past years, the LCIM has extensively studied the development, properties and applications of such sequence-defined polymer taggants. One of them was recently commercialized under the name Poltag®.
Macromolecular Information transfer
Macromolecular information transfer can be defined as the process by which a coded monomer sequence is communicated from one macromolecule to another. In such a transfer process, the information sequence can be kept identical, transformed into a complementary sequence or even translated into a different molecular language. Such mechanisms are crucial in biology and take place in DNA→DNA replication, DNA→RNA transcription and RNA→protein translation. In fact, there would be no life on Earth without macromolecular information transfer. Mimicking such processes with synthetic macromolecules would also be of major scientific relevance because it would open up new avenues for technological applications (e.g. data storage and processing) but also for the creation of artificial life. However, most of the research in that direction has been dedicated to small molecules. In this context, the LCIM explores approaches for macromolecular information transfer.