Noninvasive In-vivo Estimation of Glycated Hemoglobin Using Digital Volume Pulse Signal Based on Modified Beer-Lambert Law

Noninvasive estimation of glycated hemoglobin (HbA1c) and blood oxygen saturation (SpO2) is critical for timely and efficient management of chronic diseases such as diabetes. In this study, we provide a noninvasive HbA1c estimation method and device based on modified Beer-Lambert Law that can estimate HbA1c more accurately using DVP signals by considering differential pathlength factor (DPF). This study presents an advancement over our previous method by employing reflective digital volume pulse (DVP) signals instead of transmissive signals and a modified Beer-Lambert law-based approach using 465 nm, 525 nm, and 615 nm wavelengths. The proposed method demonstrates improved Pearson’s r values of 0.961 and 0.939 for whole-finger and blood-vessel measurements, respectively, as compared to 0.959 and 0.916 in our previous work. These advancements validate that the novel technique offers a more reliable and effective solution for noninvasive HbA1c monitoring.