This has been an area of strength for the Cavendish Laboratory in the past 20-30 years in theory and experiment alike. Today we have the facilities and expertise to study internal structure on all length scales and physical properties such as mechanical strength and rheology, phase behaviour, chirality and kinetics. We are developing an understanding of both synthetic and biological polymers (such as polysaccharides, nucleic acids and proteins). Our studies of properties from colloids, liquid crystals, elastomers and thin polymer films to protein gels and self-assembled fibrils have developed a strong and experienced research group with expertise ranging from theory to organic synthesis, to analysis by x-ray and optical scattering, rheology and electron microscopy. We work at length scales from single molecules to nm and μm supramolecular complexes.
Contact: Professor Dame Athene Donald, Professor Sir Sam Edwards, Professor Ullrich Steiner, Professor Eugene Terentjev, Dr Pietro Cicuta, Dr Ulrich Keyser, Dr Erika Eiser, Dr Easan Sivaniah
Most of what we know in Physics has been derived from experience with the inanimate world. A challenge remains to transfer some of the core physical concepts to living objects such as cells and entire organisms. Researchers at BSS are investigating properties of living cells and tissues, including their structure, mechanical responses and their interactions with substrates. Using a wide range of tools both standard (adopted from other branches of physics) and novel (developed here), we explore physics of cells and tissues, and its relevance for biological function. The aim is the transfer of our findings to medical application in the fields of improved diagnosis of diseases, studies of mechanisms of infection and production of medical devices such as implants, all with the ultimate goal of an impact on clinical practice.
Contact: Professor Dame Athene Donald, Dr Jochen Guck, Dr Pietro Cicuta
Protein folding is one of the fundamental processes in biology. Researchers in BSS are studying the underlying principles and interactions that govern this complex process in protein solutions and gels. Proteins can also mis-fold in vivo and this is associated with some debilitating diseases that are becoming increasingly prevalent, specifically the 'amyloid' diseases such as Alzheimer's, type 2 diabetes and some forms of spongiform encephalopathies, BSE and CJD. Our study of protein mis-folding therefore has interactions with the medical researchers working on these diseases, but also interacts with biology on the more fundamental level of modelling protein structure and protein-protein interactions. Protein fibrils also represent exciting possibilities in novel biomaterials with applications in cell and tissue culture, bone repair and nanoscience. The control of aggregation into suprafibrillar structures is also under investigation.
Contact: Professor Dame Athene Donald, Professor Eugene Terentjev, Dr Easan Sivaniah
We have fundamental and applied research in this area concerning the behaviour of liquids and polymers at surfaces and interfaces. Fundamental issues include the stability of thin films, and how they can be stabilised or destabilised. Control of wetting and dewetting near surfaces and the kinetics of pattern formation is important to the microfluidics community, since the transport, mixing and demixing of liquids in small channels and confined volumes is governed by the forces in the liquid interfaces. Other possible applications include the development of novel soft-lithographic techniques, thin films as anti-reflective coatings, ultra-opaque films and ultra-hydrophobic (self-cleaning) surfaces. Studies of complex polymer fluids and thin film micro-rheology with Langmuir troughs and optical tweezers is also informative to the biological and food processing community, e.g. the rheology of phospholipid films is important in the study of cell membranes.
Contact: Professor Ullrich Steiner, Dr Pietro Cicuta, Dr Erika Eiser, Dr Easan Sivaniah
A quantitative understanding of biological systems requires the construction of simplified models based on sound physical principles, whose predictions can be compared with experimental data. Theoretical physicists within the BSS sector are working closely with experimentalists to develop analytical and computational models to describe complex structures and processes occurring at the scale of molecules and cells. We work on models to describe how proteins can self-assemble into supramolecular structures such as amyloid fibrils, and the dynamic self-organisation during cell division. We study conformation and dynamics of semiflexible filaments, such as actin or microtubules and their gels. A new area of BSS activity is the computational biology of nucleic acids. Many structures they can form, such as four-stranded G-quadruplexes, RNA/DNA hybrids and microRNAs, play important roles in controlling how genes are expressed. We are using combined bioinformatic and biophysical techniques to try to understand which sequences can form these complex structures, and then to work out what their natural function is, and also whether they are amenable to targeting by novel drugs with a view to developing new therapeutics.
Contact: Professor Eugene Terentjev, Dr Julian Huppert
The BSS sector research includes innovative work in combining the existing methods of Positron Emission Tomography (PET) with Magnetic Resonance Imaging (MRI), which has the potential to bring together the advantages of both systems, i.e. attomolar sensitivity with sub-millimetre resolution and the flexibility to use a wide range of contrast agents or labelled compounds. We have developed a unique split coil magnet MRI system unit with properties designed to permit the functioning of PET detectors in the same system. The BSS researchers have developed significant expertise in image processing methodologies and have experience in handling the large datasets over networks, vital for advances in eScience such as telemedicine. BSS researchers are also developing novel biophotonics tools. These include optical traps (optical tweezers, optical stretcher, optical cell rotator), improved fluorescence imaging (white-light laser excitation), CARS microscopy, Laser Absorption Scanning Microscopy (LASCAM), and quantitative phase microscopy. These tools are applied to the study of the mechanical properties of polymers and cells, and light propagation through the retina, to name but two.
Contact: Dr Richard Ansorge, Dr. Pietro Cicuta, Dr. Erika Eiser, Dr. Jochen Guck, Dr. Ulrich Keyser
Researchers in BSS are making key advances in the emerging and exciting area of nanoscience with strong links with the current Interdisciplinary Research Collaboration (IRC) in Nanotechnology. Here we are studying structure and physical properties of polymer-based nanocomposites with thermal, photo- and electromechanical actuator properties. We are researching novel techniques for manipulating single molecules, by AFM or using surface patterning, and creating novel functionalised biopolymers with unique properties. BSS Sector researchers are also designing devices for single-molecule manipulation. These in vitro techniques, based on optical micromanipulation and use of nanopores, directly probe the basic processes on the single protein/DNA/RNA level.
Contact: Professor Ullrich Steiner, Professor Eugene Terentjev, Dr Ulrich Keyser, Dr Erika Eiser, Dr Easan Sivaniah
The Environmental Scanning Electron Microscope (ESEM), sometimes referred as low vacuum SEM, is the latest version of one of the most powerful analytic tools available to scientists. Like all scanning electron microscopes, the ESEM offers the ability to image specimens at very high spatial resolution; as high as 2 nanometres in some cases. The low vacuum environment in the sample chamber (up to 20 torr) allows users investigating samples in their natural state (wet, hydrated, uncoated, etc) without the need for conventional preparation techniques. Fields of research interest are Cryo-ESEM, dynamic studies in food science, ESEM in transmission mode, and novel contrast mechanisms in ESEM.
Contact: Professor Dame Athene Donald, Dr Richard Langford
The BSS polymer synthesis laboratory is vital in the progression from the first discovery of novel polymers to investigating and harnessing their unique properties. Such studies require a significantly larger scale of synthesis of novel polymer than is generally available to research laboratories.
Contact: Professor Eugene Terentjev
BSS has its own cell culture facilities for the preparation, culture, and analysis of various cell lines and primary cells. Simple transfections and quantitative RT-PCR are possible. Access to tissues is available through the Department of Veterinary Medicine nearby. The ability to handle biological samples in house is critical for the biological and medical relevance of BSS research.
Contact: Dr Jochen Guck, Dr Easan Sivaniah