Gibson Group News
Paper Published in The Analyst
Our latest work on exploiting carbohydrate interactions in diagnostics has been published in the RSC Journal The Analyst. We are very interested in expoiting carbohydrate (Glycan)-Protein interactions in the context of infectioud disease. For example, the symptons of Cholera poisoning (a global health issue) are caused by a carbohydrate binding protein (the Cholera Toxin). By creating nanostructures with the sugar on them, we hope to be able to detect disease at an early stage to inform clinicians and also enable appropriate use of a rapidly declining suite of antimicrobial agents. However, glycans are very promiscuous and not suited to sensors.
To overcome this we use multiplexing; essentially looking at multiple binding events, rather than 1, and generate a 'barcode' specific to the protein/pathogen. In this paper we extend this methodology to colour-changing gold nanoparticles to extract not only identification information but also concentration; a real challenge. The lead author on this paper was Dr Sarah-Jane Richards in the Group and also featured a masters research student (Denise)
Paper Published in Biomaterials Science
Our latest work on the use of polymeric ice recrystalisation inhibitors (IRIs) has been published in RSC Biomaterials Science. We have developed a series of polymers which mimic the function of antifreeze proteins, which are found in many species to enable them to survive freezing/sub zero temperatures. In this work we sought to build on our previous observations on enhancing red blood cell cryopreservation to 'harder' nucleated cell types (here and here). Typically these cells require the addition of organic solvents (DMSO) as cryoprotectants to enable them to be stored in the freezer but these can inhibit cell function, profileration and can be cytotoxic. Use several 'immortalized' (types widely used in research labs) cell lines we were able to enhance DMSO mediated cryopreservation by addition of the polymers. To really push this method, we also used primary (i.e freshly harvested) hepatocytes and found enhanced recovery.
The ability to bank cells is crucial for regnerative medicine to become a clinical reality and improved cell storage would be useful in reserach labs too. This work was a collaboration with Warwick Medical School (Dan Mitchell, Manu Vatish) and Einstein College of Medicine (Jeff Pesin).
Matt Promoted to Full Professor
Matt has been promoted to a personal chair (full professor) joint between Chemisry and Warwick Medical School. This is recognition of hard work of all team members over past 6 years!
Supramolecular Antifreeze Published
Our latest work on developing 'smart' materials has been published in RSC Polymer Chemistry. We are very interested in antifreeze protein mimetics - polymers which can slow the rate of ice growth (know as Ice recrystalisation inhibition - IRI) which have huge potential in cryopreservation of donor cells/tissue. An underlying challenge with these materials is understanding why they work. As part of our major reserach program to investigate this, we have developed polymers with essentially zero IRI activivty - but when we apply Fe 3+ ions, the polymers activity is activated. This was acheived by installation of a catechol group at the chain end (using RAFT polymerization) which promotes the formation of star-shaped polymers are higher molecular weight, triggering activity. We believe this, or similar, tools will enable us to gain more detailed understanding of the underlying mechanisms of action. This is also an analogy to how Nature works; if more protein is needed, Arctic fish up-regulate the protein synthesis. We cannot do this in chemistry, so really on the supramolecular trigger.
Cryopreservtion Published in Angewandte Chemie
Our latest work on new cryopreservation methods has been featured in the leading chemistry journal, Angewandte Chemie.
Donated cells and tissue are crucial for regenerative medicine but there is a core challenge in that the cells have short life times necessitating freezing. Current methods of cryopreservation require the addition of large amounts of organic solvent, which is non ideal and can lead to processing/toxicity challenges. In our latest paper, in collaboration with Steve Armes at Sheffield, we use self-assembled polymer micelles to provide a hydrated matrix around red blood cells. Alone, these offer little protection, but in combination with ice-growth inhibiting polymers (pionneered in our group) we get remarkable levels of recovery. Furthermore, post thawing, the micelles become worm-like and form a hydrogel. This provides a new method for direct, post-thaw 3-D tissue culture and will have many applications
Read the paper here
Combining Biomimetic Block Copolymer Worms with an Ice-Inhibiting Polymer for the Solvent-Free Cryopreservation of Red Blood Cells
Highlighted as a 'hot' paper by the journal and also a press released issued
Matt Gibson Interviewed on BBC Radio
Matt was today interviewed on BBC Coventry/Warwickshire about the the importance of maintaining blood stocks and the need for new innnovations to help this. In particular the use of cryopreservation methods being developed in the group were discussed.
Read some of our papers on this;
Deller, RC, Vatish, M, Mitchel, D., Gibson, MI., 2015. 1 789–794, ACS Biomaterials Science and Enginneering. "Glycerol Free Cryopreservation of Red Blood Cells Enabled by Ice Recrystallization Inhibiting Polymers"
Mitchell, DE., Cameron, NR., Gibson, MI, 2015, 51, 12977-12980 Chemical Communications Rational, yet simple, design and synthesis of an antifreeze-protein inspired polymer for cellular cryopreservation
Work Featured In RSC Chemistry World
A recent paper by the GibsonGroup has been highlighted in RSC Chemistry World, and also selected as a 'hot' article in Molecular Biosystems. This work, in collaboration with the FullamGroup, describes a new method for identfiying bacteria, by creating 'barcodes' describing how bacteria bind to different sugars. In the work, the team assembled small arrays of simple sugars onto a surface, and then mapped how different bacteria bind to them. This allowed a trianing matrix to be developed, so unknown bacteria could then be identified. The key to this is its simplicity and scalable to a range of different biosensory surfaces. In this preliminary work, a range of Gram Negative and Gram Postive Mycobacteria were tested and identified. This included surrogates for Mycobacterium Tubuculosis. It is hoped that this will translate to easy point of care biosensors, and to enable more effecient use of antibiotics.
Read the paper here.
Paper Published in Molecular Biosystems
Our latest paper, in collaboration with the FullamLab (Life Sciences) has been published in Molecular Biosystems. In this work we demonstrate a new, easy, concept to the identification of Bacterial species. Recently, much interest has been placed on identifying bacteria using sequencing techniques - these are excellent, but need a culturing step and bio-film forming species are a problem. They also need signifcant infrastructure, which is a challenging in the developing world. There is also the growing problem of antibiotic resistance in developed countries.
To address this we have profiled how bacteria bind to carbohohydrates (sugars). Using a simple microwell plate, we could type the bacteira based on their profile, in essence creating a barcode. We could then use this to assign blind samples. We hope to translate this to clinically relevant strains, and also to more realistic (and cheap) detection systems.
Otten, LC, Fullam, E, Gibson, M.I. Molecular Biosystems, 2016, 'Discrimination between Bacterial Species by Ratiometric Analysis of their Carbohydrate Binding Profile'