Gibson Group News
Matthew Gibson awarded an ERC Starting Grant
Dr. Matthew Gibson has been awarded a prestigious ERC (European Research Council) starting grant, with a value of €1.5 million. These grants are highly competitive and awarded on the basis of science excellence, rather than any targetted research field. Starter grants of for young academics within 7 years of completing their PhD. This grant will accerate the Group's work in the field of Antifreeze GlycoProtein (AFGP) Mimics. In particular, the GibsonGroup have pioneered the use of synthetic polymers as mimics of AFGPs, showing that they are capable of controlling ice crystal growth- The growth of ice is a huge problem in the cryostorage of donated cells and tissues, limiting their availabilty for transplantation and regenerative medicine.
There will be several PhD and Postdoctoral vacanices associated with this.
Review Article Published in Polymer Chemistry
Our review article describing how we can engineer thermally-responsive polymers to respond to biological cues has been published in RSC Journal Polymer Chemistry. The scope of this article was to show that although thermo-responsive polymers are often called 'smart' polymers, their applicaiton is limited by a single trigger (heat). Here we describe how their LCST can be tuned using subtle modifications to end-groups, side chains, or back bones to enable an 'isothermal' (no heating) response in the presence to biologically relevant triggers such as metabolites, enzymes and ions.
Read the paper here
Responsive polymers have found diverse application across polymer, biomaterials, medical, sensing and engineering fields. Despite many years of study, this has focussed mainly on those polymers which undergo thermally-induced changes – either a lower, or upper critical solution temperature. To rival the adaptability of Nature’s macromolecules, polymers must respond in a ‘smarter’ way to other triggers such as enzymes, biochemical gradients, ion concentration or metabolites, to name a few. Here we review the concept of ‘isothermal’ responses where core thermoresponsive polymers are chemically engineered such that they undergo their useful response (such as coil-globule transition, cell uptake or cargo release) but at constant temperature. This is achieved by consideration of their phase diagram where solubility can be changed by small structural changes to the end-group, side-chain/substituents or through main chain modification/binding. The current state-of-the-art is summarised here.
ACS Macro Letters Paper Published
Our latest paper on responsive polymers has been published in ACS Macro Letters.
Read paper here
Thermoresponsive polymers have attracted huge interest as a way of developing smart/adaptable materials for biomedicine, particularly due to changes in their solubility above the LCST. However, temperature is not always an appropriate or desirable stimulus given the variety of other cellular microenvironments that exist, including pH, redox potentials, ionic strength, and metal ion concentration. Here, we achieve a highly specific, isothermal solubility switch for poly(N-isopropylacrylamide) by application of ferric iron (Fe3+), a species implicated in a range of neurodegenerative conditions. This is achieved by the site-specific incorporation of (Fe3+-binding) catechol units onto the polymer chain-end, inspired by the mechanism by which bacterial siderophores sequester iron from mammalian hosts. The ability to manipulate the hydrophilicity of responsive systems without the need for a temperature gradient offers an exciting approach toward preparing increasingly selective, targeted polymeric materials.
J. Materials Chemistry B Paper Online
Our latest paper, in collaboration with Gemma-Louise Davies, has been published in the RSC J. Mater. Chem. B. This paper describes the design, and investigation of sidereophore-inpsired nanoparticle biosensors for Fe3+. Siderophores are used by bacteria to capture Fe3+ (essential for them) from environment, and have catechol groups which bind this in a highly specific manner. Inspired by this, we installed catechol groups on the corona of polymer-coated gold nanoparticles. By tuning the chemistry, we obtained gold particles which selectively aggregated in the presence of Fe3+ (but not Fe2+ or a range of other ions) giving a change in colour from red to blue. Such a simple output is appealing, for low-cost sensors. Also, the detection of Fe3+ over Fe2+ is crucial in a range of neurodegenerative diseases, inlcuding Alzheimers.
Read the paper here.
GibsonGroup work on Front cover of Biomaterials Science
Our recent paper describing the synthesis and testing of new antifreeze-protein mimetic polymers has been highlighted on the front cover of the RSC journal Biomaterials Science.
And the paper here
Carbohydrate Research Paper Published
Our latest paper probing the biological function and utility of glycosylated (sugar-functionalized) materials have been published in Carbohydrate Research, in a special issue on Nanomaterials. This work seeks to understand the potential therapeutic use of glucose-functional nanoparticles/polymers. Glucose polymers and particles have been indicated to be useful as alternatives to PEGylation, but there remains unsolved questions about their unwanted interactions with other biological systems; particularly the immune system, but also cell-surface glucose transporters (on every cell in your body!). Here we investigated how glucose materials interact with red blood cells (the cell they are most likely to encoutner when applied therapeutically). We found no evidence for either binding nor aggutination, suggesting the materials are biocompatible, at least in this model.
This work was conducted in collaboration with Gemma Davies
Matt Gibson discusses antifreeze proteins in COSMOS magazine
Matt was recently invited to discuss an exciting area of reserach for the Australian science Magazine, COSMOS. IN this Matt summarised a recent report which found that antifreeze proteins appear to not only modulate the growth of ice, but also sugars. This finding has both interesting applications in controlled crystal polymorph, for example, but also in explaining how antifreeze proteins differentiate between water, ice and sugar, which are all chemically very similar, in that they present surfaces rich in hydroxyl groups.
Matt Gibson Interviewed in Chem. Eng. News
The Group's work on antifreeze protein-mimetic polymers to enhance cellular cryopreservation has been featured in the American Chemical Society's magazine Chemical and Engineering News.
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