PhD Study : Development of hollow microneedle arrays for transdermal biosensing and drug delivery

Summary

Interest in microneedle technologies has blossomed in recent years, boasting numerous advantages over more conventional routes of administration such as improved patient compliance, painless insertion, and bypassing first pass hepatic metabolism. Furthermore, they hold the potential for delivering a diverse range of therapeutic agents, with significant scope for customisation. Low-cost, rapid fabrication and prototyping techniques have allowed what was once a complex manufacturing challenge, to move from highly specialised research environments into more accessible domains such as undergraduate laboratories, as well as mainstream medical and beauty products. These applications largely rely on the use of solid microneedle arrays, however the inclusion of a hollow microchannel brings with it significant flexibility in terms of both design and functionality.

The possibilities are considerable, and proffer the opportunity to deliver skin-impermeant compounds as well as the potential for extraction of interstitial fluid to enable real-time sampling, whilst retaining the benefits of the microneedle approach. Recent advances in digital micromirror devices (DMD), a type of micro-opto-electromechanical system (MOEMS), has brought with it significant improvements in the resolution of digital light processing (DLP) technologies.

Consisting of a rectangular array of microscopic mirrors, often hundreds of thousands of them, a DMD chip enables each mirror to be addressed and rotated individually, each corresponding to a particular pixel. The degree of rotation, typically ±10-12 °, determines the on or off state, with light being reflected onto a lens to appear bright in the on state, and reflected elsewhere (often onto a heatsink) during the off state, appearing dark by comparison.

Although commonly used in multimedia projectors, the technology has been exploited by those developing ultra high resolution 3D printing systems, capable of polymerising photocurable resins to produce features less than 20 microns in size and several microns in thickness. The fabrication of hollow microneedle arrays through the use of cutting edge additive manufacturing techniques has been demonstrated, providing scope for further investigation and design optimisation.

The candidate will be involved in the design, development and subsequent characterisation of hollow microneedle arrays and accompanying electrochemical biosensors. Additionally, a mechanism by which fluid can be drawn up through the array will be explored and investigated experimentally. The aim of the project is to move towards an all-in-one ‘smart patch’ system, utilising a feedback loop.

This approach has the potential to enable the administration of therapeutic compounds in response to biomarker detection, and thus the ability to enact complex delivery profiles. The project will necessitate the use of high resolution imaging techniques such as scanning electron microscopy and X-ray computed microtomography, as well as various spectroscopy based analytical techniques. Researchers will have access to a range of state-of-the-art fabrication equipment and analytical facilities, offering the potential to develop novel drug delivery and biosensing prototypes.

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.

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