Chris Stubbs Invited to Join SCI Materials Chemistry Committee
Chris, a 2nd year PhD student in the Gibson group, was recently invited to join the materials chemistry subcommittee of the society of chemical industry. This is a group comprised of PhD students, post-doctoral researchers, and early career academics as well as recent graduates and post-doctoral staff from within the materials chemistry industry. The intent of the subcommittee is to be responsible for representing the materials division of the SCI on social media, whilst also increasing its representation within universities, and encouraging collaboration between their industrial partners and early career principal investigators. The subcommittee is currently arranging social events, conferences and talks which engage final year undergraduates and PhD students, with the intention of encouraging them to pursue careers within the chemical industry. At the most recent meeting, Chris gave a talk entitled "Synthetic Polymers to Mimic Antifreeze Proteins".
Group Members Win Technology/Business Competition
Ben Martyn, Ben Graham. Trisha Bailey and Chris Stubbs have won first place in a Business, Innovation and Commercialisation competition for most investable pitch. This was organised by Warwick Ventures as part of our Postgraduate Transferrable skills program. Well done all!
Matt Gibson gives seminar at Birmingham University
On thursday, 9th March, Professor Matthew Gibson, gave a seminar at the University of Birmingham. This was part of the Physical Sciences for Health series. In this, Matt discussed the groups past resutls in designed new polymers to mimic antifreeze proteins. He showed the evolution from simple mimics to more advanced polymers and even some non-antifreeze proteins, which have surprising antifreeze-like activity. He also introduced the relatively new topic (to the group) on controlling ice nucleation. The medical and biotechnological applications were also discussed. He even managed to link cruical science discoveries to moments from the Empire Strikes Back...
Caroline wins poster prize
Caroline won the first place poster prize at the Symposium on Nanoscience and Nanotechnology, held at the University of Birmingham in December. This is her third poster prize to-date.
Paper published in Biomacromolecules
Our latest work investigating the role of regiochemistry in the design of synthetic ice recrystallisation inhibiting materials has been published in Biomacromolecules. We have previously shown that poly(ampholytes) (mixed positive and negative charges) are an exciting class of synthetic materials which display IRI activity while also being highly tuneable, compared to poly(vinyl alcohol), the only other potent polymer IRI. In this work we overcame two challenges of making ampholytes by conventional polymerization; Obtaining an exact 1:1 ratio of the charges and ensuring a perfectly alternating structure. This was achieved by using maleic anhydride copolymers, which has a propensity to cross propagate. This level of sequence control is unusual for most polymerisation reactions and can only be achieved through specific monomer combinations. The activity of these polymers with a range of comonomers and pendant amine groups was investigated and increasingly hydrophobic side chains (but not backbones) increased activity.
These polymers were then compared to a structurally similar polymer in which the charged groups are randomly incorporated, which had less activity, demonstrating for the first time that polymer sequence actually has a large impact on this property.
Read the paper here
Paper published in Journal of Polymer Science Part A
Our latest work has been published in the Journal of Polymer Science Part A. In this work we have synthesised and characterised gold nanoparticles coated with RAFT-synthesised polymer chains. We describe how the two different polymer coatings effect the properties of the nanoparticles, in the context of grafting density, buffer stability, and in a lectin binding assay. We found that poly(oligoethylene glycol methacrylates), despite being widely used particle coatings, lead to low grafting densities which in turn resulted in lower stability in biological buffers. In comparison poly(vinylpyrrolidones) resulted in stable particles with higher grafting densities due to the compact size of each monomer unit. This work forms a link between our previous studies on the polymer coating of gold nanoparticles and the surface grafting of polymers onto gold and glass supports. These results will guide the development of new nanoparticle biosensors with enhanced specificity, affinity, and stability both within our research group and the wider scientific community.
Read the paper here
Paper published in Antonie van Leeuwenhoek
Our latest work, in collaboration with Michela Corsaro in Naples has been published. We are very interested in identifying new biological macromolecules which can interact with ice, or act as cryoprotecants for cells (or organisms) in extreme environments, as new targets for synthetc mimics. In this work, the Corsaro group synthesised sulphated polysaccharides, related to previously identified cryoprotecant polysaccharides. Detailed structural chracteriseation was undertaken. Surprisingly, it was found to have far weaker ice recrystalisation activity than the polysaccharide extracted from the extremophile organism (Colwellia psychrerythraea) indicating that some other structural features are involved in its function.
Read the paper here
New Paper in European Polymer Journal
Our latest work investigating how the architecture (shape) of synthetic ice growth inhibitors affects their function is now online in the European Polymer Journal. We have previously shown that poly(vinyl alcohol) is a potent inhibitor of ice crystal growth; a proeprty normally only found in antifreeze (glyco) proteins from polar fish species. We have also found that inhibiting ice growth lets us enhance the cryopreservation of donor cells, for regenerative medicine. However, we are still not certain of how this polymer functions. In this work, we developed a new tri-functional RAFT (or MADIX) agent to enable us to make 3-arm, star branched polymers. We foudn that the third arm was essentiall non-active, having the same activity as a 2-arm star (i.e. linear polymer). This suggests that hydrodynamic volume, not valancy (number of potental binding sites) is the key marker of activity and might suggest that the mode of action is not entirely due to direct ice binding
Read the paper here