Optical fibre-based minimally-invasive blood glucose monitoring system.

Viswambaran, Vivek

Abstract

Obesity and changing lifestyles have made diabetes mellitus one of the world’s foremost metabolic syndromes, affecting the lives of around 380 million people worldwide. Although considered incurable, adverse effects of diabetes can be controlled by tightly monitoring blood glucose levels. Several methods to accomplish this have been proposed over the years. In this thesis, a thorough literature and patent review revealed that blood glucose monitors (BGMs) based on amperometry are one of the most common technologies to have been developed and used. However, these sensors are problematic. They are invasive in nature and have bio-compatibility issues. Also, these electrochemical sensors are rendered unstable due to the electroactivity of other blood constituents, therefore requiring frequent recalibration. These drawbacks highlight the need for an alternative solution. This thesis shows that optical fibre can act both as a sensing element and a medium to carry information in real time. Optical methods are useful as they require a very small sample volume (< 1 μL) and are also capable of remote probing. An investigation into various microstructured optical fibres was conducted and analysed mathematically, resulting in the proposal for an integration of microstructured optical fibre and associated techniques. Boronic acid-based glucose sensing moiety has been selected due to its high affinity for glucose and its ability to decouple from glucose, making it a good contender for a continuous or reusable blood glucose sensor. Preliminary investigations concluded that 4-vinylphenylboronic acid (VPBA) can be incorporated into poly(methylmethacrylate) (PMMA) matrix without losing its ability to bond with glucose. Further, the study achieved the successful fabrication of a VPBA and Rhodamine-6G (Rh-6G) doped optical fibre ring resonator, the performance of which was also analysed mathematically. Rh-6G retained its fluorescence properties even after doping with PMMA and VPBA, and after the fibre-drawing process. This can be helpful when creating a microresonator with the lasing gain medium. The results of this study can be taken forward and extended to in vitro and in vivo studies with blood or blood substitute.

Citation

VISWAMBARAN, V. 2018. Optical fibre-based minimally-invasive blood glucose monitoring system. Robert Gordon University [online], MRes thesis. Available from: https://openair.rgu.ac.uk

• Thesis Type: Thesis
• Deposit Date: Aug 13, 2019
• Publicly Available Date: Aug 13, 2019
• Keywords: Bioengineering; Optical fibre sensors; Diabetes; Blood glucose monitoring
• Public URL: https://rgu-repository.worktribe.com/output/348634
• Award Date: Oct 31, 2018