|Based in the School of Chemistry, we are organic chemists performing creative and imaginative research in the field of polymer chemistry. Our interests lie in applying organic and polymer syntheses with supramolecular principles towards the development of responsive and adaptable nanoparticles and materials with potential applications in molecular recognition and sensing, catalysis, medicine and materials science. 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, the regional development agency OneNorthEast and the Nuffield Foundation.|
News and Research Highlights
Making Silicon Brighter
Nanoparticles based upon semi-conductor materials are potentially very useful in the life sciences because of their unique fluorescent properties, which allow the fate of these nanoparticles within cells to be tracked using microscopes. However, many of these nanoparticles contain cadmium, which is highly toxic to cells. At Newcastle we are developing a class of silicon nanoparticle (sometimes known as silicon quantum dots), which are fluorescent but lack the toxicity associated with many other semi-conductor nanoparticles. We have recently shown in the journal Nanoscale that the fluorescence of silicon nanoparticles can be enhanced by co-encapsulating them alongside gold nanoparticles inside of larger polymer nanoparticles. It is well-known that gold nanoparticles can enhance the fluorescence of nearby species, and by co-encapsulating both gold and silicon nanoparticles within a larger polymeric package ensures that they are spatially close to one another. Co-encapsulation also improves processability, and we have shown that the composite nanoparticles can be inkjet printed onto surfaces. These composite nanoparticles are expected to widen the scope of applications for both silicon and noble metal-nano devices. This work was performed by DAF group member Noor Aniza Harun, in collaboration with Dr Matthew Benning (School of Mechanical and Systems Engineering) and Dr Ben Horrocks (School of Chemistry). Read the article by clicking here.
Transmission electron micrographs showing Au nanoparticles encapsulated inside of larger polymer nanoparticles (about 100 - 150 nm in diameter). Because Si is essentially transparent in this technique, its presence is confirmed in separate spectroscopic experiments.
Investigating Templating in Polymer-Scaffolded Dynamic Combinatorial Libraries
The desire to create receptors which can recognise selectively and bind target molecules has been a topic of much interest in chemistry. Our approach to this challenge is based upon a new type of dynamic combinatorial library—the polymer-scaffolded dynamic combinatorial library (PS-DCL)—a twist upon the dynamic combinatorial libraries concept established by the groups of Sanders and Lehn. We believe PS-DCLs are ideally suited for the discovery of new wholly-synthetic macromolecules capable of selective molecular recognition. In this work we show that PS-DCLs can respond to templates in ways which can be rationalized, and that changing structural features of the scaffold can have unanticipated effects. Read more about this work in Polymer Chemistry by clicking here.
May 2012 DAF spoke about stimuli-responsive polymer nanoparticles at Christian-Albrechts Universität zu Kiel in the north of Germany in a trip warmly hosted by Prof Thisbe Lindhorst.
December 2011 Alex Jackson spoke about his work on introducing stimuli-responsiveness into polymeric nanoparticles at the RSC Postgraduate symposium in Nanotechnology in Birmingham (December 2011), winning the prize for best presentation!
PhD position starting October 2013: The DAF group are accepting applications for a PhD studentship in Adaptive and Responsive Polymer Systems. Click here for more information.
March 2013 Clare Mahon wins best student talk at the RSC Chemical Nanoscience symposium held in Newcastle for a talk highlighting recent progress in polymer-scaffolded dynamic combinatorial libraries.
December 2012 To gel and back! The DAF group report in top journal Angewante Chemie how polymeric nanoparticles can reversibly transform into a covalently cross-linked hydrogel. We believe that this is the first example of the reversible interconversion of two different polymer architectures (nanoparticle to gel) where each species is covalently cross-linked. The trick is the use of dynamic covalent bonds, which can facilitate the rearrangement of the polymer chains from nanoparticles into the hydrogel. This work was lead by Daniel Whitaker, a visiting researcher in the DAF group, and Clare Mahon, a final year PhD student. Read this article here.
October 2012 Alex Jackson's review article which highlights recent progress in the field of stimuli-responsive and adaptive polymer nanoparticles is published in Polymer Chemistry. Click here to read.
October 2012 The DAF group welcomes Sarah Upson, who will be working on a EU-framework 7 project with Dr Matt German (School of Dentistry) and Prof Kenny Dalgarno (Mechanical Engineering) to develop new polymeric materials for use in maxillofacial implants.
October 2012 DAF is "Author of the Week" in the Polymer Chemistry Blog. Read the interview here!
September 2012 Clare's paper investigating templating in polymer-scaffolded dynamic combinatorial libraries is published in Polymer Chemistry. Click here to read.
July 2012 DAF gave an invited talk at the excellent Warwick 2012 polymer conference. Niza also presented a poster on her work using miniemulsion polymerization chemistry to encapsulate silicon quantum dots inside polystyrene nanoparticles.
June 2012 Alex Jackson, the first member of the DAF group, successfully defended his PhD thesis. Joining in October 2008, Alex spent a very productive three years exploiting dynamic covalent bonds to make new stimuli-responsive polymer nanoparticles. His work has shown the potential of imparting stimuli-responsiveness with dynamic bonds, and to date has lead to co-authorship of an impressive seven peer-reviewed publications. He will soon be off to a postdoctoral position at A*STAR in Singapore to develop polymeric drug delivery systems. Congratulations to Alex, who is off to work as a research scientist at A* Institute of Chemical and Engineering Sciences (ICES) in Singapore, where he will work on the development functional and biocompatible polymeric nanoparticles for targeted PET imaging .
April 2012 Clare Mahon delivered a lecture at the RSC Organic Division North East section annual meeting at York in March. Clare outlined her recent progress in polymer-scaffolded dynamic combinatorial libraries, showing how they can respond to macromolecular templates and also how properties of the polymer scaffold can influence the levels of response. This is Clare’s second invited lecture of her PhD studies, haven spoken at the European Science Foundation’s High Level Research Conference on Systems Chemistry in Crete (October 2011).