Polarimetric glucose sensing in aqueous humor utilizing digital closed-loop control

The development of a non-invasive glucose sensor would be beneficial to patients inflicted with diabetes mellitus. In this study, polarimetric glucose sensing using both water and the aqueous humor of the eye doped with glucose are investigated. The polarimeter developed for this research differs from previously investigated systems in that it utilizes a digital closed-loop control system. In vitro results were obtained for both water and bovine aqueous humor mediums using a hyperglycemic concentration range of 100-600 mg/dl in 50 mg/dl increments. Both water and aqueous humor data sets exhibit a high degree of linearity with correlation coefficients of 0.9997 and 0.9925, respectively. The computed linear regression models yielded standard prediction errors of 4.207 mg/dl and 20.24 mg/dl, respectively. Future research will focus on coupling light in and out of the eye as well as problems encountered due to the birefringence of the cornea.