Research progress of tear glucose detection

Wen Xin, Zhang Mingzhi. Research progress of tear glucose detection[J]. Chin J Exp Ophthalmol, 2025, 43(4): 368-372. DOI:10.3760/cma.j.cn115989-20220915-00430.

Diabetic retinopathy (DR), a common microvascular ocular complication of diabetes mellitus, is a leading cause of irreversible blindness among the working-age individuals.Among several factors, high blood glucose level is the key risk factor affecting DR progression.Therefore, blood glucose monitoring is important for DR patients.Currently, glucometers and continuous blood glucose monitoring systems are widely used to monitor blood glucose levels in clinical practice and at home.Since these two methods are both invasive, high-frequency detection, and require regular calibration and replacement, many researchers have been dedicated to continuous and noninvasive detection of glucose.It has been found that the levels of some metabolites in biological fluids can be significantly correlated with the state of ocular or systemic diseases, which could be used as biological indicators for noninvasive detection.Due to the positive linear correlation between tear and blood glucose concentrations, tear glucose level could reflect the fluctuations of systemic and ocular glucose levels.Moreover, tears could be collected by noninvasive methods.Therefore, a new research hotspot has been formed around glucose biomarkers combined with biomaterials and physical sensors.This article reviews the origin and transport of tear glucose, the correlation between tear glucose and blood glucose and DR, and the noninvasive monitoring of tear glucose.