Research Opportunities
From LAGWiki
We are always interested in high quality applicants to join our group. We offer both experimental and theoretical projects and most include elements of both. Please contact us for available opportunities.
We investigate reaction kinetics in technical and biological flows using laser spectroscopic imaging techniques. The techniques are fast and sensitive and applicable both for studies in the gas phase and in liquid phases. Applications range from the studies of reactions in the atmosphere to live cell spectroscopy.
Our research is multidisciplinary in nature and we welcome applications from strong candidates from all disciplines of engineering and the natural sciences. We would be happy to discuss the suitability of individual projects with interested candidates.
[edit] Available PhD projects in Microscopy
We are looking for a PhD student to work in a joint collaboration between the Laser Analytics Group and Prof. A. Venkitaraman's group at the Hutchinson/MRC Research Centre. The aim of the project is to develop and apply advanced microscopy methods for the investigation of the functional dynamics of BRCA2 and Rad51 proteins in relation to cancer. The research will make use of state-of-the-art biophysical techniques, including super-resolution techniques such as Foerster Resonance Energy Transfer Microscopy and Fluorescence Correlation Spectroscopy, as well as Fluorescence Lifetime Imaging Microscopy.
Applicants should have a first class degree (or equivalent) in biophysics, physics, optical engineering or other relevant disciplines, excellent communication skills and a desire to work in a multidisciplinary research team involving physicists and biologists. Previous experience in biological research is highly desirable.
[edit] Imaging Protein Function inside living cells
This project aims at studying the function of protein-protein interactions directly at the live cell level using advanced microscopy techniques such as fluorescence resonance energy transfer (FRET) and fluorescence lifetime imaging microscopy (FLIM), using the advanced optical imaging facilities available in the group. The techniques will be used for drug discovery research directly at the single cell level. The project is in collaboration with Dr. Jonathon Pines of the Wellcome Trust/Cancer Research UK Gurdon Institute in Cambridge focussing on protein switches of the cyclin-cdk family, which are implicated in cancer. Drugs which prevent this switch from forming have potential as anti-cancer agents. The fluorescent techniques to be developed in this project will have the power to rapidly screen for novel drugs in vivo to assess their therapeutic potential.
[edit] Confocal microscopy using supercontinuum photonic crystal fibre laser technology
This project is in collaboration with Leica Microsystems, Germany and Fianium Ltd, UK and aims to harness the potential of novel supercontinuum light sources for microspectroscopy applications. We have available to us a unique laser source, giving picosecond (ps) pulses at MHz (106 Hz) repetition rates and emitting light over the entire visible spectrum down to the near infrared (430 nm to 2000 nm). The aim of the project is to couple the supercontiuum radiation into Leica's latest and most advanced confocal scanning microscopy system and develop a technique permitting spectrally resolved fluorescence lifetime measurements. The technique will not only gives us information on the concentration of chemical species at the sub-micrometre scale, but also information on the environment the fluorophore is in, such as viscosity, temperature and pH. The project employs the latest developments in photonic technology and includes elements of advanced optical engineering
[edit] 3D deconvolution microscopy to assess properties of live malarial cells
Malarial blood cells loose some of their ability to deform when sheared leading to a change in the blood's rheological properties. This can lead to clots with potentially fatal consequences. Our group has succeeded to image the deformation of live blood cells through different stages of the parasitic cycle of the infection using a technique called confocal deconvolution microscopy. This yields images of unprecedented resolution and structural clarity. The current project aims to enhance the technique using modern computational algorithms for the deconvolution process and subsequent quantification of properties such as deformation and volume change, which is in the femtolitre range. The project will involve experimental and numerical work and is in collaboration with Dr. V. Lew and Dr. T. Tiffert of the Department of Physiology in Cambridge.
[edit] Imaging transport dynamics inside living cells
The uptake of molecular compounds into living cells is critical for targeted delivery applications and drug discovery research. Using a special live cell reactor system and time lapse confocal fluorescence microscopy we aim to follow the cellular uptake of polymer systems which have been designed for targeted delivery and biodiagnostics applications. The system has potential for example to deliver anticancer drugs to malignant tissue and to provide contrast between diseased and healthy tissue. The molecular compounds are being designed in the BioScienceEngineering group (Prof. Slater) and the project is collaborative and mostly experimental in nature.
[edit] Imaging chemistry in microfluidic devices
We perform collaborative research with the Fisher group to image chemistry inside microfluidic channels. Very well defined concentration and acidity gradients can be set up within these devices (see left picture) and chemical compounds can be screened as they flow down these devices. We use a technique called Fluorescence Lifetime Imaging Microscopy to give us information on the flows and aim to use this to monitor the growth of nanoparticulate structures which form in the mixing region between two parallel streams. The project includes experimental and modelling aspects and includes elements on microfluidic channel fabrication, advanced microscopy techniques and application of Finite Element modelling of flows.
[edit] Available PhD projects in Sensor Design
[edit] Diode laser sensor for flame temperature measurement
Temperature is a crucial parameter in the investigation of combustion since the rates of chemical reactions, such as those leading to the formation of important pollutants like NOx and soot, are highly temperature dependent. Accurate measurements of flame temperature are thus vital to improve our understanding of combustion and as input to numerical simulations. A world-unique temperature sensor based on the use of blue diode lasers has already been developed within the Laser Analytics Group. The sensor works by probing indium atoms seeded to flames. The aim of this project is to increase the measurement speed of this sensor by a factor of 103, permitting time resolved measurements in turbulent flames, of great interest due to the complex interactions of fluid mechanics with flame chemistry. Ultimately such sensors could be used to control and optimise combustion in novel gas turbine and SI engines.
[edit] Wavelength agile spectroscopy for studies of fluidised bed combustion
Fluidised beds are widely used for gas-solid reactions, an important example being the combustion or gasification of fuels. The purpose of the current project, which will be performed in close collaboration with the group of Dr. John Dennis, is to develop a sensor capable of probing the gas phase reactions inside a fluidised bed, using laser spectroscopic techniques. This will enable chemical reactions occurring in the fluidised bed to be observed in situ with a time resolution sufficiently short to see interactions between fluid mechanics and chemistry. The ideal laser source for this purpose would combine high acquisition speed with a wide spectral tuning range, to cover all species of interest. One promising approach, fulfilling both criteria, is dispersing the broad spectral output (>1000 nm) of a pulsed supercontinuum source in highly dispersive fibres to achieve a rapid wavelength sweep permitting scanning over hundreds of nanometres in microsecond sweep times. The project makes use of the most recent advances in fibre laser and photonic crystal fibre (PCF) technology.
[edit] On-line laser diagnostics in high temperature fuel cells
This is a project in collaboration with Rolls-Royce Fuel Cell Systems Ltd. to develop a novel fibre laser based sensor for on-line gas analysis, and to employ it to assist in the development of industrial fuel cell systems. The sensor will be implemented into prototype solid oxide fuel cells (SOFC) manufactured by Rolls-Royce plc. SOFC technology is considered as one of the strongest candidates for future large-scale power applications, as it features a high thermodynamic efficiency and very low pollutant emissions. The sensor to be developed will be used to monitor fuel and product gas compositions in real time under running conditions. Aims are to study the complex reactions taking place in the SOFC stacks, and aid in the practical development and optimisation. The results of these measurements will feed directly into the SOFC development programme at Rolls-Royce.
[edit] Frequency mixing of diode lasers for trace detection of pollutant species
Concern over safety and the environment requires increasing control on the emission of toxic species from industrial plants. It is therefore crucial to be able to measure accurately tiny concentrations of pollutant species in waste gases; ideally such measurements would be performed in situ to minimise the lag time in identifying process upsets. A promising tool for doing this is to use diode laser absorption spectroscopy, capable of detecting trace components at part-per-billion levels. Many relevant species have strong absorption lines in the ultra-violet spectral region where no diode lasers are available. We aim to generate appropriate UV light by non-linear frequency conversion of standard diode lasers in special crystals. Target species that could be detected through this approach include NO, SO2, mercury, for which there are no alternative diagnostic techniques.
[edit] Distributed Sensor networks for quality and process control in pharmaceutical plants
This project is in collaboration with GlaxoSmithKline and aimed at the development of novel optical sensor elements which are cheap, reliable and quick enough to respond to dynamic changes in process conditions. Key aims are methods for the detection of chemical impurities or detection of global system changes through parameters such as temperature, refractive index or viscosity. The sensors are intended for monitoring of reactant streams in production lines of large scale pharmaceutical plants. Using diode sensing elements distributed over large networks we hope to be able to replace current employed batch analysis techniques such as HPLC and mass spectrometry, which are very expensive and time consuming, with integrated and cheap in situ on line sensors. The project will involve integrating optical technology with microfluidic device fabrication as well as elements of control systems engineering.
[edit] Carbon nanotube reactor diagnostics
In the Department of Materials Science and Metallurgy, the group of Prof. Alan Windle have succeeded in the direct spinning of carbon nanotube fibres from the gas phase, in a continuous catalytic vapour deposition process. In the process the gas stream reaches temperatures exceeding 1200C, resulting in atomisation of Fe from ferrocene, from which the nanotubes then grow. The objective of the proposed project is to develop and apply dedicated laser based sensors, capable of resolving hydrocarbon chemistry in situ in the high temperature chemical vapour stream. Species of interest include CO, OH, Fe, FeS, SOx - about none of which there is currently any quantitative information - and also the size distribution of catalyst particulates and nanotubes in the gas phase. Ultimately, it is hoped to obtain sufficient data to understand the complex process of the fibre production.
