Fluorescent sensors could help researchers see diabetes in action

Researchers at the University of Bath have developed fluorescent molecular probes that can detect glucose changes inside living animals, offering a way to observe sugar uptake and metabolism in real time. The probes combine boronic acids, chemicals that selectively bind to sugars, with advanced imaging methods. In experiments, the team showed that the probes could detect glucose changes in cultured cells and in living zebrafish, a common model for studying metabolism. The work was published in *Advanced Science* and involved collaborators from the University of Bath, University of Birmingham, Universidad Autónoma de Madrid, the Spanish National Research Council, and STFC Rutherford Appleton Laboratory.

The key advance is that the probes were paired with multiphoton fluorescence lifetime imaging microscopy, a technique that tracks changes in how long a fluorescent signal lasts rather than simply measuring brightness. In zebrafish larvae, several probes accumulated in the digestive system and changed their fluorescence after an external glucose challenge. The researchers also used the method to distinguish insulin-deficient zebrafish with a diabetes-like mutation from healthy siblings; the diabetic fish showed reduced fluorescence linked to elevated glucose levels. While this is still a research tool rather than a clinical diagnostic test, it could help scientists study how glucose moves through tissues, how metabolic dysfunction develops, and how potential diabetes treatments affect living systems. The team also suggested the platform could eventually be adapted to detect other carbohydrates or metabolic markers relevant to diabetes, cancer, drug discovery, and precision diagnostics.