UC San Diego

Diabetes is one of the fastest-growing chronic diseases worldwide, with diabetic ketoacidosis (DKA) significantly increasing the risk of complications and comorbidities. Effective diabetes management relies on accurate and timely blood glucose and ketone levels monitoring. Yet, traditional methods like frequent finger-prick blood tests or urine tests are invasive, inconvenient, and often delay the detection of critical metabolic changes. This thesis explores the development of a Continuous Ketone Monitoring (CKM) system using an electrochemical microneedle biosensor. Ketone bodies, specifically β-hydroxybutyrate, are a key indicator of metabolic state and disease progression in diabetes. This work focuses on developing and validating a novel microneedle sensor capable of continuous, real-time monitoring of ketone levels directly from the interstitial fluid by building on the principle of electrochemical sensing, biocatalytic reactions, and microfabrication. The CKM system offers a minimally invasive, real-time alternative to traditional monitoring methods, by addressing many of their limitations and advancing it by proposing enhancements to overcome these challenges such as mediator leaching, HBD/NAD+ immobilization, minimally invasive ISF BHB testing, and on-body testing. The sensor’s performance was evaluated through a series of experiments, including in vitro and on-body tests, indicating promising accuracy and reliability compared to existing methods. By providing continuous feedback on ketone levels, CKM technology has the potential to significantly improve diabetes management, prevent DKA, and enhance patient compliance and quality of life. The study offers critical insights into their potential impact on the future of diabetes care. The findings suggest that this technology could represent a significant leap forward in the pursuit of improved diabetic health monitoring and management.