PhD Study : Bioactive glass encapsulation for the localised delivery of antimicrobial agents

Apply and key information  

Summary

It is estimated that between a quarter and a third of all hospital acquired infections occur at surgical sites. These infections can be difficult to treat as they frequently feature multidrug resistant bugs; furthermore they are often not tackled until complex antibiotic resistant biofilms have formed. Reports suggest that elderly patients with a surgical site infection due to methicillin-resistant Staphylococcus aureus (MRSA) have an 11-fold increased risk of mortality. Infected sites often require surgical revisions which further increases the financial burden on the health service through prolonged hospital stays. An average surgical site infection can require up to ten additional hospital days and cost thousands of pounds.

The project proposes to develop novel, site specific, preventative antimicrobial coatings to address these issues specifically in relation to bone infections. There is clearly an unmet need to develop antimicrobial resistant implant materials. Simply sterilising implants prior to surgery is insufficient given that microbes are routinely present on the patient’s skin and can access wounds during surgery. Bioactive glasses are clinically used for repairing small bone defects however these materials have no innate antimicrobial properties.

Furthermore due to the high temperatures used during the manufacturing process it is not possible to incorporate organic antimicrobial agents during the preparation of the glasses. Here we propose, to develop novel chemical linkers that can attach organic antimicrobial drugs to the inorganic glasses. The coatings will be bio-degradable to provide a controlled release of the antimicrobial agent. The plan is to coat the bioactive glasses with a thin layer of bio-degradable carbohydrate (a small polymer) and then attach the antimicrobial agents to this carbohydrate coating. The bioactive glasses will be manufactured in-house carefully characterising the size and morphology of the surface using techniques such as XPS, SEM and FTIR.

The carbohydrate will then be adsorbed to the surface of the glass to ensure the desired coating is achieved. The carbohydrate coated glass will then be carefully loaded with antimicrobial agents such as gentamicin. Absorption rates of the carbohydrate and antimicrobial agents will be monitored by HPLC and FTIR. In vitro release studies will be performed to assess the release kinetics to ensure the optimal delivery rates of the antimicrobial agents are achieved. HPLC assays will be used to monitor the kinetics.

The antimicrobial efficacy of these composites will be tested against a range of clinically relevant microbes. The biocompatibility and safety of these composite drugs will be assessed using cell culture techniques including MTT assays of osteoblast cell lines. Initially this project will focus on coating 45S5 Bioglass® (which is already FDA approved and in clinical use in humans) with gentamicin (which is also FDA approved).

Synergistic benefits conferred by the composite will therefore have the potential to make an immediate impact as prior approval will expedite the time taken from clinical trials to market.  The second phase will seek to develop antimicrobial glasses and to chemically link a wider range of antimicrobial agents in conjunction with additional therapeutic agents.

Essential criteria

Applicants should hold, or expect to obtain, a First or Upper Second Class Honours Degree in a subject relevant to the proposed area of study.

We may also consider applications from those who hold equivalent qualifications, for example, a Lower Second Class Honours Degree plus a Master’s Degree with Distinction.

In exceptional circumstances, the University may consider a portfolio of evidence from applicants who have appropriate professional experience which is equivalent to the learning outcomes of an Honours degree in lieu of academic qualifications.

  • Sound understanding of subject area as evidenced by a comprehensive research proposal
  • Clearly defined research proposal detailing background, research questions, aims and methodology

Desirable Criteria

If the University receives a large number of applicants for the project, the following desirable criteria may be applied to shortlist applicants for interview.

  • Completion of Masters at a level equivalent to commendation or distinction at Ulster
  • Experience using research methods or other approaches relevant to the subject domain
  • Sound understanding of subject area as evidenced by a comprehensive research proposal
  • Work experience relevant to the proposed project
  • Publications record appropriate to career stage
  • Experience of presentation of research findings
  • A comprehensive and articulate personal statement
  • Relevant professional qualification and/or a Degree in a Health or Health related area

Funding and eligibility

The University offers the following levels of support:

Vice Chancellors Research Studentship (VCRS)

The following scholarship options are available to applicants worldwide:

  • Full Award: (full-time tuition fees + £19,000 (tbc))
  • Part Award: (full-time tuition fees + £9,500)
  • Fees Only Award: (full-time tuition fees)

These scholarships will cover full-time PhD tuition fees for three years (subject to satisfactory academic performance) and will provide a £900 per annum research training support grant (RTSG) to help support the PhD researcher.

Applicants who already hold a doctoral degree or who have been registered on a programme of research leading to the award of a doctoral degree on a full-time basis for more than one year (or part-time equivalent) are NOT eligible to apply for an award.

Please note: you will automatically be entered into the competition for the Full Award, unless you state otherwise in your application.

Department for the Economy (DFE)

The scholarship will cover tuition fees at the Home rate and a maintenance allowance of £19,000 (tbc) per annum for three years (subject to satisfactory academic performance).

This scholarship also comes with £900 per annum for three years as a research training support grant (RTSG) allocation to help support the PhD researcher.

  • Candidates with pre-settled or settled status under the EU Settlement Scheme, who also satisfy a three year residency requirement in the UK prior to the start of the course for which a Studentship is held MAY receive a Studentship covering fees and maintenance.
  • Republic of Ireland (ROI) nationals who satisfy three years’ residency in the UK prior to the start of the course MAY receive a Studentship covering fees and maintenance (ROI nationals don’t need to have pre-settled or settled status under the EU Settlement Scheme to qualify).
  • Other non-ROI EU applicants are ‘International’ are not eligible for this source of funding.
  • Applicants who already hold a doctoral degree or who have been registered on a programme of research leading to the award of a doctoral degree on a full-time basis for more than one year (or part-time equivalent) are NOT eligible to apply for an award.

Due consideration should be given to financing your studies. Further information on cost of living

The Doctoral College at Ulster University

Key dates

Submission deadline
Friday 5 February 2021
12:00AM

Interview Date
Weeks commencing 15th and 22nd March 2021

Preferred student start date
Mid-September 2021

Applying

Apply Online  

Contact supervisor

Dr Deborah Lowry

Other supervisors