Development of Sweat and Saliva Glucose Sensors as Alternative for Non-Invasive Blood Glucose Monitoring

Abstract

This study aimed to develop a paper-based glucose sensor using artificial sweat and saliva samples, a non-invasive, practical, and affordable concept for measuring glucose levels. The chosen method was the colorimetric method using the Glucose Oxidase (GOx) enzyme, Horseradish Peroxidase (HRP) enzyme, and 3,3′-diaminobenzidine (DAB) chromogen. The wax stamping method was utilized on a piece of filter paper to test the glucose sensor. The test was carried out in several stages, including testing various concentrations of reagents and wax stamping sizes, fabricating the glucose sensors, and testing multiple concentrations of glucose, artificial sweat, and artificial saliva. The RGB method was used to test the resulting color. The data obtained were then validated using UV-Vis Spectrophotometry. The GOx concentration on the glucose sensor affected the color change velocity. The HRP, DAB, and wax stamping size concentration simultaneously indicated a strong correlation with changes in the color intensity that appeared on the glucose sensor. The glucose sensor in this study could measure the glucose concentration of the artificial sweat and saliva samples, respectively, from 0-3000 μM with R 2 = 0.9862 and 0.9987. This study proved a strong correlation between the reagents' concentration and the color intensity on the developed glucose sensor.