Laser-induced graphene: novel approaches for sensing and drug delivery applications

Abstract

Laser-induced graphene (LIG) has emerged as a versatile and accessible form of graphene which has been used to accelerate the development of environmental and medical sensing systems, and drug delivery. While the electrical properties of LIG are known, its ability to serve as the basis of a viable device inevitably requires new approaches that can modify its interfacial properties and confer selectivity. As such, chemical manipulation of LIG electrode substrates has been investigated for a range of potential applications and integrated with the appropriate electronic control.

A novel active release mechanism has been demonstrated where LIG, in combination with a new composite polymer-based phase change material, was used as a microheater to control release of the model therapeutic, curcumin. The design of a nanostructured copper layer to provide selectivity towards nitrate has also been described. The reaction mechanism was elucidated, and the results validated through the analysis of authentic surface waters. The modification of LIG with a novel chitosan (CS):carbon nanoparticle (CNP) layer was found to be sensitive to humidity and its translation to wound monitoring has been critically evaluated. The use of a riboflavin modified LIG electrode assembly in combination with a 3D printed support was employed as a disposable sensor for the in situ monitoring of ileostomy fluid. The probe represents the first report of a wearable system for sensing pH within a drainable collection pouch. Finally, the laser induced creation of graphene carbon directly on the hydrocolloid adhesive within an ostomy pouch baseplate was achieved. This direct method of producing LIG greatly simplifies sensor design and its applicability was demonstrated through its use as a moisture sensor for detecting leakage of ileostomy fluid. In each case, a holistic approach has been taken in which the chemistry, materials and electronics have been characterised to yield novel devices.

Thesis embargoed until 30 June 2026

Date of Award	Jun 2025
Original language	English
Supervisor	Karl Mc Creadie (Supervisor), Aaron Mc Conville (Supervisor) & James Davis (Supervisor)