Coordination polymer approach to DNA functionalisation and assembly

Biological self-assembly, whereby molecules organise themselves into well-defined functional architectures and hierarchical systems, has inspired new approaches to materials synthesis and device fabrication. These, so-called, bottom-up methods offer the possibility of lower cost, smaller size and increased functionality and complexity. Among the most successful of these methods are those based on DNA, biology's information carrier. DNAs robust nature, reliable synthesis, controllable length scale, combined with the deep understanding of the genetic code's structure-building rules address many of the criteria desired of a materials design toolkit. However, the native biopolymer lacks a range of interesting physico-chemical properties; its electronic system is relatively quiescent. To overcome this various strategies have been developed. Most widely adopted are the incorporation of pre-synthesized components such as nanoparticles, chemical modification, or deposition of metals and inorganic materials directly onto the DNA to form electrical wires, for example.

In this proposal we will explore a new molecular-based approach for preparing functionalized DNA-based materials and self-assembled molecular architectures that also offers a possible route to a simple DNA-based electronics. This approach will use modified DNA components, thionucleosides, that have different metal-binding properties compared to those of the native biopolymer. These thionucleosides can assemble metal ions into extended chains forming, so-called, coordination polymers which have useful optoelectronic properties, including electrical conductivity. Using this approach, the project aims to pioneer a new type of material that combines these functional coordination polymers with DNA. These metal-based polymers can introduce, at once, luminescence, semiconductivity and distinct chiral optical properties. Furthermore, they establish thermally-stable linkages into the parts of the structure, introduce addressable electrically-conducting regions into the molecular architecture and also sites of potential new reactivity.

By allowing the incorporation of new properties via this novel route new types of construction protocol, compositional architectures and combinations of material properties will be possible. As a result the project will advance the field of bottom-up molecular design, specifically DNA-based materials, towards increased functionality and so expand the available toolkit for future developments.

People Impact: The project will have significant impact through developing the career of the PDRAs by providing training and broad experience in leading-edge coordination chemistry, molecular and bio-materials research. Along with preparative and synthetic skills the researchers will enhance their expertise in structure/property analysis (e.g. spectroscopy, microscopy, electrical measurements etc.) and develop deep subject-specific expert knowledge. The researchers will also benefit from the career and professional skills development opportunities offered by the host institutions. Training the next-generation of scientists is vital for the UK as a knowledge-based economy.

Economic: The work outlined in this proposal will lead to significant advances in supramolecular/coordination/biomaterials chemistry with the development of novel DNA-compatible coordination polymers. Such basic research is critical to the design and discovery of new functional materials that underpin next-generation product development and technologies across numerous industrial and commercial sectors. While the project is fundamental in nature with commercialisation considered longer-term, there is significant worldwide interest in DNA-based technology and materials beyond academe. This is motivated by their potential for applications in areas such as nanoelectronics, sensing, bio-assays, therapeutics, computing, plasmonics, programmable materials, lithography, etc. Commercial products and industrial development in DNA-based nanomaterials is evident in companies such as Merck (SmartFlare Live cell RNA detection), Luminex/Nanosphere Inc. (Verigene bacterial and virus detection) and Touchlight Genetics (nanoelectronics, aptamers, smart materials). All these products/concepts have emerged from basic academic research of the type proposed here and our project on DNA-based materials has similar potential.

Outreach: In the first instance, key results will be highlighted on the University web pages as they arise and Universities Press Offices will provide advice and professional support for communicating research-based news articles via more mainstream media outlets. The applicants have a track record of informing a wider audience of the research via feature articles in general science/technology publications, schools visits and engagement with teachers and these will continue to be used as appropriate opportunities are created.

In summary, we will deliver the following to achieve impact:
Open-access publications in top-rank peer review journals to ensure availability to widest audience (industry, academic, public, media)
Presentation at national and international conferences and to industry when appropriate
Identification of exploitable results and possible commercialisation routes
Host annual research symposium