Development of microneedle systems for transdermal sensing

: new routes to assessing cardiovascular health

Abstract

Healthcare systems are under increasing pressure to decentralise blood analysis procedures, especially with the burden of an ageing population and the lengthy processing times associated with laboratory analysis. Of late, there has been a significant push towards developing point of care diagnostics that would overcome many of the issues surrounding conventional methods of blood withdrawal and subsequent examination. It has been recognised that a smart sensor, capable of monitoring a variety of biomarkers in situ would radically transform disease management, providing earlier diagnosis and therefore, more timely intervention.

In light of this, the core strategy of the project research outlined herein was largely focused on the formation of a minimally invasive transdermal method of assessing cardiovascular health. The design and development of a composite microneedle biosensor has been described, with the vision of potential for future integration within a smart wearable system. Multiple formulations for low-cost rapid production of conductive carbon-based microneedle arrays were investigated. The facile means of microfabrication, and inclusion of carbon nanoparticulate, afforded further exploration by application of a variety of electrochemical modification techniques. The composite microneedle arrays were assessed by numerous characterisation techniques, validating the efficacy of their capability to penetrate the stratum corneum of skin, whilst
maintaining sensing functionality.

The electroanalytical performance of the microneedle arrays was demonstrated by the detection of clinically relevant biomarkers within biologically complex media. An attractive feature of the composite system, being the interchangeability of material composition, lends itself to not only biosensing, but also, transdermal drug delivery. As such, the electroanalytical capacity of the microneedle design was beyond initially anticipated. This facilitated proof of concept exploration of a composite microneedle system capable of harmonious biosensing and consequential release of a therapeutic drug. Numerous applications which would benefit from the composite microneedle approach have been investigated and its commercial feasibility critically appraised.

Date of Award	2021
Original language	English
Awarding Institution	Ulster University
Sponsors	Eastern Corridor Medical Engineering Centre
Supervisor	James Davis (Supervisor)