Advanced biophotonic materials: developing a toolkit for quantum dot-membrane-protein nanocomposites


Contact Dr Peter G. Adams or Dr Kevin Critchley to discuss this project further informally.

Project description

Photosynthesis is essential for life on Earth and the light-absorbing proteins involved are a great source of inspiration for biophysicists. In contrast, quantum dots (QDs) are tiny inorganic semiconductor nanoparticles of great technologic interest. “Light-harvesting” (LH) proteins, found in plant biomembranes, absorb photons of light using a network of coordinated pigment molecules (e.g. chlorophylls). Energy absorbed by LH proteins is transferred as excited electronic states through membranes >100 nm with remarkable quantum efficiency (>90%). Yet, LH proteins are limited to specific biological pigments and their absorbance spectrum has gaps where solar photons are not harvested. QDs can absorb photons of a wide range of energies and transfer the energy to other molecules. The excellent optical properties of QDs make them an ideal partner for channelling energy to (or accepting energy from) LH proteins (Nabiev et al., 2010; Werwie et al., 2012). A modular, self-assembled system of membranes (lipids), QDs and proteins could have distinct advantages as a nanotechnological system for controlled energy- and electron-transfers. There is also great interest in understanding the fundamental underlying photonic processes involved.

The project objectives include: (1) Design, generate and characterize a membrane-based system that combines QDs with photosynthetic proteins in order to increase the absorption cross-section and thus spectral range of photosynthesis. (2) Study how energy, and electron, transfer from QD is affected when they are interfaced with this biohybrid system. (3) Investigate use of your membrane/QD materials for applications to nanotechnology (e.g. functional thin-films). You will systematically compare nanocomposites of different compositions for particle stability and optical properties, for example: (i) QDs embedded into the lipid bilayer or tethered to the membrane surface, (ii) QDs embedded within polymer micelles (iii) interfacing the above with a series of photosynthetic membrane proteins (LHCII, PSI, PSII), (iv) trialling QDs of different chemistries and sizes.

You will use a range of world-class biophysical tools including: spectroscopy to characterize optical properties (absorbance, fluorescence, other) and various high-end microscopies to visualize the particles at high resolution (atomic force microscopy, fluorescence microscopy, electron microscopy), showing the improvement that QDs make over the protein alone.

References 1. Nabiev, I., Rakovich, A., Sukhanova, A., Lukashev, E., Zagidullin, V., Pachenko, V., Rakovich, Y.P., Donegan, J.F., Rubin, A.B., and Govorov, A.O. (2010). Fluorescent Quantum Dots as Artificial Antennas for Enhanced Light Harvesting and Energy Transfer to Photosynthetic Reaction Centers. Angewandte Chemie International Edition 49, 7217-7221. 2. Werwie, M., Xu, X., Haase, M., Basche, T., and Paulsen, H. (2012). Bio Serves Nano: Biological Light-Harvesting Complex as Energy Donor for Semiconductor Quantum Dots. Langmuir 28, 5810-5818.

Entry requirements

Applications are invited from candidates with or expecting a minimum of a UK upper second class honours degree (2:1), and/or a Master's degree in a relevant science subject such as (but not limited to) physics.

How to apply

Formal applications for research degree study should be made online through the university's website. Please state clearly in the research information section that the PhD you wish to be considered for is 'Advanced biophotonic materials: developing a toolkit for quantum dot-membrane-protein nanocomposites’ as well as Dr Peter. G Adams as your proposed supervisor.

If English is not your first language, you must provide evidence that you meet the University’s minimum English Language requirements.

If you require any further information please contact the Graduate School Office

We welcome scholarship applications from all suitably-qualified candidates, but UK black and minority ethnic (BME) researchers are currently under-represented in our Postgraduate Research community, and we would therefore particularly encourage applications from UK BME candidates. All scholarships will be awarded on the basis of merit.