AN OPTICAL APPROACH FOR BLOODLESS, IN-VITRO AND NON-INVASIVE GLUCOSE MONITORING

Abstract

Diabetes mellitus (DM) indicates elevated glucose concentration in blood. In type 1 diabetes, the pancreas produces inadequate insulin whereas in type 2 diabetes, the body is incapable to utilize the insulin present. Insulin is required to transport glucose into the cells. The insulin resistance by the cells causes the glucose level in the blood to increase. At present, the clinical methods available to diagnose DM are invasive. The diagnosis of DM is done by either pricking the fingertip or drawing blood from the vein followed by the quantification of blood glucose in terms of [Formula: see text]. Continuous monitoring is limited as skin is punctured or venous blood is extracted. Spectroscopic analysis of hair, nail, saliva and urine possess the potential to differentiate the hyperglycaemic from the healthy subjects facilitating non-intrusive diagnosis of diabetes. The variation in the incident wavelength following the interaction with the sample is measured by a spectrometer. Based on the energy of the excitation source, the molecular structures present in the sample will either vibrate or absorb and emit photons that produce a spectrum. The samples were collected from both the groups of subjects and pre-processed prior to further examination. The samples were then characterized using the Fourier-transform infrared (FTIR) spectroscopy. The spectral output was pre-processed, filtered and analyzed so as to discriminate between the diabetic and healthy subjects. Although the spectral band of nail and hair samples appears to be identical, a difference in the amplitude was observed between both diabetic and normal subjects at 1450, 1520, 1632, 2925 cm[Formula: see text]. The area under curve (AUC) in the range of 3600 to 3100 cm-1 is a prominent marker in the discrimination. The peak wavelength and AUC were utilized as a biomarker to discriminate the diabetic and normal individuals.