A Glucose sensing contact lens: A new approach to non-invasive continuous physiological glucose monitoring

摘要

We have developed a new technology for the non-invasive continuous monitoring of tear glucose using a daily use, disposable contact lens, embedded with sugar-sensing boronic acid containing fluorophores. Our findings show that our approach may be suitable for the continuous monitoring of tear glucose levels in the range 50 - 500 μM, which track blood glucose levels that are typically ≈ 5-10 fold higher. We initially tested the sensing concept with well-established, previously published, boronic acid probes and the results could conclude the used probes, with higher pK_a values, are almost insensitive towards glucose within the contact lens, attributed to the low pH and polarity inside the lens. Subsequently, we have developed a range of probes based on the quinolinium backbone, having considerably lower pK_a values, which enables them to be suitable to sense the physiological glucose in the acidic pH contact lens. Herein we describe the results based on our findings towards the development of glucose sensing contact lens and therefore an approach to non-invasive continuous monitoring of tear glucose using a contact lens.