Tunable nanomaterials for controlled drug release in smart devices

  • Ashleigh Anderson

Student thesis: Doctoral Thesis


The majority of conventional controlled release technologies tend to be based
around encapsulant systems in which a polymeric binder or gel typically responds to changes in the local environment in which the delivery device has been placed. The contents are often released when the particle, capsule, film or droplet is exposed to the appropriate physico-chemical trigger (typically a change in pH) with the timerelease-dose delivery characteristics controlled through manipulation of the encapsulant formulation. The adaptation of this core strategy for use in the next generation of transdermal microdevices or smart patch is explored. The core rationale of this work relates to the development of microneedle patches and other delivery architectures, which upon activation by an appropriate electrochemical trigger, leads to the release of a drug.

The methodology adopted herein focused on the use of cellulose acetate phthalate (CAP) as pH sensitive barrier films structured for use within a number of microscale
(patch, implant, microneedle and microdroplet) devices. The barrier film was used as a means of entrapping a model drug with the controlled release of the latter achievedthrough the exploitation of the hydrogen evolution reaction. The application of an electrode potential resulted in an increase in the local pH thereby inducing the controlled dissolution of the barrier film and facilitating the release of the drug.

A variety of approaches have been investigated leading from the use of standalone CAP films through to its direct incorporation as a component in the electrodematerial itself. The design and characterisation of the carbon composite material from a film to the development of conductive microneedles and electronic sutures is described. The ability to electrochemically manipulate the structural integrity of thecomposite structures and the ability to affect the controlled release of model drugs is critically appraised.
Date of AwardSept 2018
Original languageEnglish
SupervisorJames Davis (Supervisor) & Pagona Papakonstantinou (Supervisor)

Cite this