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

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.

Biodegradable, Non-Enzymatic, Non-Invasive and Cost-Effective Ethanol Sensing Material and Its Electrochemical Characteristics

“…They have covalently immobilized alcohol oxidase on the surface of a graphite electrode which is polymerized with 9-methyl-9Hcarbozole-3-carbohydrazine (MCCH).Alternatively, Debasis Maity et.al., (2018) [20] reported about a layer-by-layer spray coating of multi-walled carbon nanotubes (MWCNT) and PVA on commercially available cotton fabrics and subsequently the ethanol gas sensing properties were determined at room temperature. This work is in continuance with our previous work on the same material for its glucose sensing ability studied and presented in detail [21].…”

Pt/MXene-Based Flexible Wearable Non-Enzymatic Electrochemical Sensor for Continuous Glucose Detection in Sweat

“…Chronoamperometry (CA) was used to evaluate the peak at −0.1 V. As shown in Figure b, different curves are obtained for different solution concentrations of glucose (0–1 mM) after 60 s. Figure c shows the calibration curve, and the current shows a good linear relationship with the glucose concentration in the range of 0–1 mM, with a correlation coefficient of 0.9793. Based on the slope of the line fitting, the sensitivity is calculated as 3.43 μA mM –1 cm –2 , and the limit of detection is 29.15 μmol L –1 (S/N = 3), which is in the range of human sweat detection in clinical trials . For comparison, Table S1 lists the analytical performance of other Pt-based non-enzymatic glucose electrodes and enzymatic glucose electrodes for sweat glucose detection along with our findings.…”

“…Based on the slope of the line fitting, the sensitivity is calculated as 3.43 μA mM −1 cm −2 , and the limit of detection is 29.15 μmol L −1 (S/N = 3), which is in the range of human sweat detection in clinical trials. 35 For comparison, Table S1 lists the analytical performance of other Pt-based non-enzymatic glucose electrodes and enzymatic glucose electrodes for sweat glucose detection along with our findings. It can be observed that a relatively higher sensitivity was obtained on our fabricated sensor.…”

Research Progress on Biomimetic Nanomaterials for Electrochemical Glucose Sensors

“…[ 126 ]. Among these molecules, glucose in sweat has good correlation with glucose in blood, which has been used in noninvasive electrochemical wearable sensors [ 7 , 103 , 122 , 127 , 128 , 129 ]. However, the normal level of sweat glucose is less than 0.2 mM, which is lower than that in blood serum, with the range of 5.6–6.9 mM.…”

“…As biomimetic materials, cellulose-based function materials also are used in sweat glucose sensors. For example, Ramadoss et al [ 128 ] reported glucose oxidase-free polymer materials made of polyelectrolytic cellulose derivatives and an organic polycarboxylic acid for glucose sensing properties by electrochemical analysis.…”