Non‐Invasive, Non‐Enzymatic, Biodegradable and Flexible Sweat Glucose Sensor and Its Electrochemical Studies

Abstract

Abstract Glucose oxidase‐free polymer composite sensing material, made of polyelectrolytic cellulose derivatives cross‐linked by an organic polycarboxylic acid and enhanced by a plasticizer, is reported. The polymer composite is a nontoxic material and is also biodegradable that degrades within 15 days in the soil. The material is extremely flexible and yet resilient in such a way to explicitly fit for application in wearable sensors. Electrochemical analysis of the material for glucose sensing properties with artificial sweat as the electrolyte revealed surprising results. The lowest detection limit observed in chronoamperometric analysis was 0.4 mM of glucose. Impedimetric analysis showed significant drop in impedance at 0.5 mM addition of glucose. The cellulose composite material gets reduced into H 3 O + and H + ions, on addition of glucose, which is confirmed through square wave analysis, chrono‐amperometry, impedance and cyclic voltammetry results. The changes in the functional group were also confirmed by FTIR analysis taken before and after the addition of glucose. Results obtained by electrochemical analysis were well correlated with the proposed reaction mechanism. The flexibility and strength of the cellulose composite film was analysed with nano‐indenter, it also showed an excellent folding endurance withstanding up to 86960 folds. The biocompatibility nature of the material was also tested with the help of 3T3 fibroblast cells.