Miniature Enzymatic Biosensors for Tear Glucose Measurement in Capillary Tubes

Abstract

Miniature enzymatic electrochemical sensors were fabricated and applied to detect tear glucose concentrations in anesthetized rabbits. Three µL of tear fluid was sampled from under the lower eyelid via a glass capillary, and the miniature sensor was then inserted into the solution within the capillary for detection. Boluses of insulin were administrated to the rabbits to lower the elevated blood glucose concentrations caused from anesthesia. A significant correlation was found between tear and blood glucose levels, suggesting that tear glucose measurements are a potential, minimally invasive alternative for glucose monitoring.