Teaching plastic to be fantastic Current approaches to polymer synthesis are relatively imprecise in comparison to natural methods. Researchers in the SCPs project are drawing inspiration from nature as they aim to develop new methods of synthesising sequence controlled polymers, which could have interesting new functions, as Professor Rachel O’Reilly explains A lot of
attention in chemistry research over recent years has been focused on controlling the molecular weight of a polymer, now Professor Rachel O’Reilly and her colleagues in the SCPS project are looking towards the next level of complexity in development. This involves thinking not just about controlling the molecular weight of a polymer, but also actually controlling the individual monomer units and how they’re located along the polymer chain. “We’re investigating the sequence of how the monomers are put together. So we’re trying to find methods of controlling how the monomers are put together,” says Professor O’Reilly. Methods have already been developed for this purpose by scientists, yet many are specific to a particular type of monomer; Professor O’Reilly is taking a slightly different approach. “We are looking to draw inspiration from the ribosome and think about templation and segregation, to allow for control of monomer additions,” she outlines. This research is built on strong foundations, as Professor O’Reilly and her colleagues in the project hold long experience in polymer investigation. A lot of inspiration is drawn from nature in this work. “We’ve been working on programming DNA and templating chemistry, so looking at how you can use DNA sequences to
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New approaches developed for the synthesis of sequence controlled polymers using DNA templated chemistry or polymer template approaches.
induce specific small molecular reactions, and thinking about how we might bridge some of those very specific oligomers. Then we can look to learn from some of the templation methods we use in that to try and extrapolate that to develop robust methods for polymers,” outlines Professor O’Reilly. The chemistry in a polymer chain
has not historically been utilised to expand function, now researchers are looking to manipulate it, with the goal of developing sequence controlled polymers. “If you reorder a polymer, or fold it, or assemble it in a particular way, you can do a lot more rather than just by self-assembly,” explains Professor O’Reilly.
EU Research
SCPS Developing sequence controlled polymers for organization, templation and recognition
Sequence control The current focus in the project is on achieving precise sequence control, which effectively means controlling where the actual monomers are placed within the polymer chain. The questions around this are being addressed in different ways within the project. “In one part of the project we’re really thinking about precision, about trying to make perfect polymers. In another part, we’re looking at more approximate approaches, where we might not need to make perfect polymers,” explains Professor O’Reilly. This does not mean developing entirely new chemistries, but rather using known monomer units in a different way. “We’re not making new polymers in the sense of new chemistries and new functional groups - we’re using monomers that have been used before, but we’re putting them together in such a way that they behave differently,” continues Professor O’Reilly. “We are using polymerization methods and DNA-templated chemistries, to try and
to put functionality in a particular place,” says Professor O’Reilly. This research could help lay the foundations for the future development of materials with particular properties tailored to certain functions. However, Professor O’Reilly says the project’s work is more exploratory at this stage, rather than being directed towards the development of a specific material. “It’s very much about discovery and developing the methods and routes at the moment,” she stresses. One of the major challenges in this area is that researchers do not know the end result of these methods, so Professor O’Reilly is also involved in another programme running in parallel to the SCPs project, looking to relate the composition of the polymer to its eventual properties. “We’re working together with colleagues from the University of Oxford, looking to try and do discovery. So this is about being able to make libraries of materials, looking at their functions, and then going back a step to learn more about their sequence,” she outlines.
We’re looking at more generalised approaches, so then we can use new methods to grow particles that have sequence specificity, in the sense that we are able to put functionality in a particular place embed certain molecules into our polymer materials.” A lot of the tools currently used to assemble these materials are relatively basic. Hierarchical self-assembly and folding have not historically been used to generate function in polymers, but if researchers can fold polymers in a particular way, Professor O’Reilly believes new possibilities may emerge. “We might be able to start to get some more interesting functions,” she says. Using selective recognition or crystallisation enables researchers to make fundamentally different shapes or constructs, that might have new functions because of both their shape and their chemistry. “One of the sequence elements we’re interested in is using crystallisation to drive the formation of nanostructures, which is quite difficult as it requires quite pure phases. We’re looking at more generalised approaches, so then we can use new methods to actually grow particles that have sequence specificity, in the sense that we are able
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Project Objectives
Current approaches in polymer synthesis lack the precision and complexity of natural polymers such as proteins which use just 20 amino acid monomers in a 1D specific sequence to give 3D structures such as enzymes with specific functions such as catalysis. Or DNA which uses just 4 nucleobase monomers in specific sequence to store and propagate information. As polymer scientists we have more monomers available but don’t yet have robust methods to program a sequence and hence connect them in a controlled manner. This means we can’t yet access some of the advanced functions of natural SCPs. The aim of this grant is to develop robust chemical approaches for the synthesis of SCPs to enable us to bridge the biological-synthetic materials divide as well as go significantly beyond the current state of the art.
Project Funding
ERC Consolidator Grant - Synthetic Chemistry and Materials
Contact Details
Project Coordinator, IDEAS-ERC Professor Rachel K. O’Reilly FRSC Chair in Chemistry School of Chemistry University of Birmingham Edgbaston Birmingham B15 2TT T: +44 (0)121 414 7757 E: r.oreilly@bham.ac.uk W: https://www.oreillygrouplab.com/ W: http://www2.warwick.ac.uk/fac/sci/ chemistry/research/oreilly/oreillygroup Twitter: @RORgroup
Rational design This could in the long-term lead to a more rational, tailored approach to materials development, while new avenues of investigation are also emerging out of the project’s research. While one important outcome from the project is the development of methods for preparing SCPs, another is simply demonstrating the wider potential of polymers. “There’s actually a lot more to a polymer than just a coil,” stresses Professor O’Reilly. In future, Professor O’Reilly plans to continues her work in this area, looking to build a deeper understanding of polymer synthesis and the development of precision materials. “We’re starting to think about discovery in our collaboration with the group in Oxford, so making libraries of compounds,” she outlines. “Basically we’re trying to make our approaches a bit more scaleable in a combinatorial sense. We might be able to make a certain quantity of a material, now we’re looking at making many different derivatives, and seeing if we can select for function.”
Professor Rachel O’Reilly
Professor Rachel O’Reilly is Chair of the Chemistry Department at the University of Birmingham. She is interested in using polymer synthesis and precision synthesis to allow for the preparation of functional and responsive nanostructures, which can be utilised in a wide range of applications, from materials science to medicine.
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