PhD Opportunity

World-Leading St Andrews Scholarship in Optoelectronics2021 entry

The University of St Andrews is pleased to offer a full scholarship funded by St Leonard’s Postgraduate College, to support an exceptional student undertaking doctoral research in the following project:

Developing and Measuring Antimicrobial Photodynamic Therapy

Deadline: Monday 1st March 2021

Project description

Multidrug resistance of pathogenic bacteria has become a serious threat to public health. The growth of resistance to antibiotics means that antimicrobial resistance (AMR), including bacteria, fungi and viruses, could overtake cancer as a cause of death, make what is now routine surgery very dangerous, and lead to a huge burden on health care systems, families and societies. Topical treatment of bacterial infections of the skin is an important area where further resistance can be created. Finding novel approaches to combat (multidrug resistant) bacteria has therefore become very important.

One approach with significant potential is the use of photodynamic therapy (PDT). PDT is a treatment which uses light in combination with a light-sensitive drug to generate reactive oxygen species that then kill neighbouring cells. It is used in many parts of the world to treat common skin cancers (e.g. basal cell carcinoma). So far, PDT has used large and expensive hospital-based light sources, notably lasers, filtered lamps or large arrays of LEDs. These cumbersome light sources have limited its use to specialized centres that have the particular equipment required.

Recent advances in optoelectronics enable compact wearable light sources to be made. The aim of this project is to combine expertise in physics and medicine to develop organic light-emitting diodes (OLEDs) that can be used to make light-emitting bandages capable of killing bacteria (and other micro-organisms), and to develop measurements to show their effectiveness.  OLEDs are particularly appealing for this use because they are very thin light sources that emit over an area with high efficiency and can be flexible.  An important part of the PhD research will be to develop OLEDs with properties tailored to killing microbes (e.g. bacteria and protozoa) by PDT. For this application, the OLEDs need to work at very high brightness. Most OLEDs (and other light sources) lose efficiency at very high brightness, and so the physics of the processes controlling efficiency will be explored. In particular, exciton-exciton annihilation can be a significant loss mechanism, so we will measure it, and then develop mechanisms such as widening the recombination zone to reduce it.

The student will contribute to work on developing optical measurements of the effectiveness of PDT for killing bacteria. The traditional way of performing such studies is to grow bacteria on plates, and count colonies under a microscope. It is slow and painstaking work. Instead, we will measure the effectiveness of PDT using a sensitive optical method that enables changes in bacterial growth to be detected quickly.  The project aims to demonstrate that this provides a new and powerful way to assess and optimize PDT.  This in turn will enable us to determine the activity of PDT and any synergistic effect of photosentisers in real-time. After developing and validating this new approach to measuring the effectiveness of PDT, we will proceed to optimize the conditions for effective PDT.  Key parameters to optimize are light intensity, duration, choice of photosensitiser (the light-activated chemical) and concentration of photosensitiser.


The innovative and distinctive features of the project are:

  • Using PDT as an alternative to antibiotics for killing dangerous bacteria and microbes
  • Developing a new approach to measuring the effectiveness of antimicrobial PDT
  • Developing OLEDs as compact wearable light sources for antimicrobial PDT

At the end of the project we aim to have demonstrated:

  • A new approach to evaluating the effectiveness of photodynamic therapy
  • That PDT using organic light-emitting diodes can be effective for killing antibiotic resistant bacteria and protozoa
  • Optimised conditions for effective PDT using OLEDs

The student will be supervised by Dr Robert Hammond, Professor Stephen H. Gillespie, and Dr Ben Parcell (School of Medicine) and Professor Ifor D. W. Samuel (School of Physics and Astronomy).

Informal enquiries regarding this scholarship may be addressed to Dr Robert Hammond – email

Funding notes

Duration of award

Up to 3.5 years. The successful candidate will be expected to have completed the doctorate degree by the end of the award term. The award term excludes the continuation period and any extension periods.

Value of award

The award covers full tuition fees for the award term as well as an annual stipend payable at the standard UK Research Council rate (the 2021-22 annual rate is £15,560).

How to apply

  1. Apply for admission as a doctoral student. Please see the advice on Research programmes.
  2. After submitting the research application form in step 1, you will receive an email with details on how to access the Scholarships and Funding catalogue, where you can apply for the World-Leading St Andrews Scholarship.
    • Enter the catalogue by following the instructions in the email and clicking View the scholarships and funding catalogue to apply.
    • Select 2021/2 as the Academic Year and click Refresh list.
    • Locate World-Leading St Andrews Doctoral Scholarships in the list of scholarships (using the filter box if necessary), click Apply and complete the application form.
    • You can also use the catalogue to search and apply for other scholarships for which you are eligible.

As part of the scholarship application you will be required to upload a personal statement. This should serve as a cover letter for the research project application as a whole, and should include:

  • An outline of your suitability for the project (project criteria can be found in the “Eligibility” and “Project Description” sections above).
  • Why the project interests you.
  • What you would bring to the project in terms of previous skills and expertise.
  • Any ideas that you may have for the realisation of the project.

Please contact with any enquiries about the scholarship application process.