|Based in the School of Chemistry at Newcastle University, we are organic chemists performing creative and imaginative research in the fields of polymer and supramolecular chemistry. Here you can find out more about what’s going on in our laboratory, including our current and research. The DAF group are based in the School of Chemistry's Chemical Nanoscience Laboratory, and have received generous funding from EPSRC, EU-FP7, The Royal Society, and the regional development agency OneNorthEast.|
News and Research Highlights
Orthogonal Bond Breaking and Forming
The design and study of functional systems of molecules is an area of interest within the growing field of systems chemistry. The concept of orthogonality, which is well-established in synthetic chemistry, has started to emerge as a powerful tool to embed increased sophistication into functional systems. Stunning examples of e.g. molecular machines, interlocked molecules, dynamic combinatorial libraries and responsive materials have all recently emerged where orthogonal supramolecular interactions lie at the heart of their unique features.
So-called dynamic covalent bonds (DCBs) present possibilities as potential orthogonal supramolecular interactions, and in this work (click here) we demonstrate how two well-known DCBs—disulfide and imine bonds—can be selectively cleaved and reformed in the presence of the other upon the application of orthogonal stimuli. Key to this achievement is the judicious choice of reaction partners to ensure that no unwanted competing processes are present, and the establishment of well-defined operating limits within which the system is shown to retain its orthogonality.
This work will pave the way for the future development of more complex responsive chemical systems and materials.
Templating carbohydrate polymers with lectins
Carbohydrate-protein interactions are important in biology, playing important roles in cell-cell interactions and infections caused by viral and bacterial pathogens. For example, cholera is caused by proteins secreted by the Vibrio cholera bacteria and which start their process of cell infection by binding to carbohydrates displayed on the surfaces of cells. Consequently, there has been much effort to understand better carbohydrate-protein interactions with the aim of developing effective inhibitors which may lessen the effects of the cholera toxin.
In work described in Organic and Biomolecular Chemistry (click here), we describe a conceptually new method for preparing synthetic polymers which can bind to heat labile toxin, a carbohydrate binding protein which is structurally very similar to cholera toxin. Our method uses the protein itself to act as a template, onto which the polymer binds and selects carbohydrate residues which improve its binding affinity from a pool of residues. These residues can adapt their positions upon the polymer to maximize their binding with toxin. We show that the polymer is able to enhance its binding by about one order of magnitude, selecting those carbohydrate residues which presumably promote stronger binding and discarding those which do not. We anticipate that we will be able to build upon this proof of concept and develop polymers which can bind more strongly to carbohydrate-binding proteins.
July 2015 We are happy to welcome Dr Gema Dura to the group. Gema is a graduate of University of Castilla-La Mancha in Spain, where she completed a PhD in coordination/supramolecular chemistry. After a short postoctoral stay she has moved to Newcastle to begin on a new project involving hydrogel materials derived from polymeric proteins.
June 2015 Michael's paper in Chemical Communications is published. This work shows that, with care, disulfide and imine bonds can be selectively broken and reformed in the presence of one another, opening the door for next generation stimuli-responsive materials. Click here.
June 2015 DAFs article about the poor retention of secondary school chemistry teachers in UK secondary schools is published in the June issue of Chemistry World magazine. Click here.
January 2015 Clare's paper describing a new approach towards the design of carbohydrate polymers which bind lectins is published in Organic and Biomolecular Chemistry. Click here.
December 2014 Ben Murray (2009-2011) will soon be joining the faculty of Hull University as a lecturer in Inorganic Chemistry. Well done to Ben!
November 2014 DAF presented the work of Dan Coleman and Marta Pujol on siRNA delivery at the Emerging Nanomaterials for Healthcare symposium at Warwick University.
October 2014 The group are happy to welcome Dr Antonio Ruiz-Sanchez and Ahmed Ejaz. Antonio will be working on anti-biofouling coatings and Ahmed will be working on single-chain polymer nanoparticles.
September 2014 Niza’s paper on composite nanoparticles which can simultaneously display enhanced luminescence and Raman spectra has just been published in Chemical Communications. Click here to read article.
August 2014 Congratulations to Clare for successfully defending her PhD dissertation. Proving that quality always beats quantity, her thesis came in at less than 100 pages. Clare is now the third PhD student to graduate from the DAF group. Clare will be joining the lab of Dr Bruce Turnbull at Leeds University on an EPSRC Doctoral Fellowship.