Comparisons of Optical Properties of Glucose Sensing by Mueller Matrix Polarimetry Using Infrared and Visible Wavelengths

A Mueller matrix polarimetry system with 1650 nm wavelength is developed to extract the mean absorbance and anisotropic properties of turbid media as an enabling technology for non-invasive glucose sensing. It shows that the mean absorbance (Ae), depolarization index (Δ), and optical rotation (γ) vary linearly with the glucose concentration. These findings highlight the interdependence of these parameters and their significance in characterizing the optical properties of glucose. Moreover, when conducting human testing, it was observed that glucose exhibited a notable time delay at the 532 nm wavelength instead of the 1650 nm wavelength. Furthermore, it was observed that the absorption of glucose at 532 nm is lower than at 1650 nm. Regarding the optical rotation, the response at 1650 nm is much clearer than that at 532 nm. This can be explained by the fact that the optical rotation reaction at 532 nm is more susceptible to interference from other interfering substances than at 1650 nm, leading to cancellation of each other out. As a result, the mean absolute relative deviation (MARD) value for the polarimetric system at 1650 nm wavelength is 1.8334%, and the correlation coefficient (R2) value for 1650 nm wavelength is 0.97629. It is found that the MARD and R2 values for the polarimetric system at 532 nm wavelength, developed by the same group, have poorer results in terms of system accuracy and the linear relationship of the model, respectively. These observations suggest that using 1650 nm is more effective in accurately predicting the behavior of glucose in human tests.