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

Abstract

Wearable non-invasive sensors facilitate the continuous measurement of glucose in sweat for the treatment and management of diabetes. However, the catalysis of glucose and sweat sampling are challenges in the development of efficient wearable glucose sensors. Herein, we report a flexible wearable non-enzymatic electrochemical sensor for continuous glucose detection in sweat. We synthesized a catalyst (Pt/MXene) by the hybridization of Pt nanoparticles onto MXene (Ti3C2T x ) nanosheets with a broad linear range of glucose detection (0–8 mmol/L) under neutral conditions. Furthermore, we optimized the structure of the sensor by immobilizing Pt/MXene with a conductive hydrogel to enhance the stability of the sensor. Based on Pt/MXene and the optimized structure, we fabricated a flexible wearable glucose sensor by integrating a microfluidic patch for sweat collection onto a flexible sensor. We evaluated the utility of the sensor for the detection of glucose in sweat, and the sensor could detect the glucose change with the replenishment and consumption of energy by the body, and a similar trend was observed in the blood. An in vivo glucose test in sweat indicated that the fabricated sensor is promising for the continuous measurement of glucose, which is essential for the treatment and management of diabetes.

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.…”

“…MXene (Ti 3 C 2 T x ) as a 2D transition metal carbon material has been used in wearable sensors because of its excellent conductivity, biocompatibility, and flexible tensile property [ 55 , 103 , 132 ]. As seen in Figure 11 A, Li et al [ 103 ] used Pt/MXene as active sensing materials for nonenzymic electrochemical glucose detection, and it exhibited a broad linear range of glucose detection (0−8 mM) under neutral conditions. In addition, with the protection of a conductive hydrogel, the stability of Pt/MXene glucose sensor was enhanced and could be used in a glucose sensor.…”

Smart-Phone-Assisted Optical Biosensors Based on Silk-Fibroin-Decorated Reduced Graphene Oxide Quantum Dots for Fluorescent Turn-On Recognition of l-Dopa

“…47 Compared to other fluorescent sensors, AIE-or AIEE-based sensors achieved remarkable attention because of their simplistic mechanism, beneficial for the development of turn-on sensors, high detecting ability in an aqueous medium, etc. 35 The reduced form of the GO process has unique fluorescence properties in the nanorange due to its specific band gap that falls in the semiconductor range. 48 Core−shell quantum dots offer a notable advantage over ordinary quantum dots for their increasing photoluminescence efficiency because the electrons and holes are more effectively present in the pair in the core and the dangling bond on the surface.…”

“…Real-time monitoring of key biomolecules in the human body is vital in terms of biomedical applications where a variety of biosensing media, including blood serum, urine samples, sweat samples, cells from various organs, pharmaceutical tablets, etc. , Recently, Li et al used Pt/MXene-based flexible wearable sensors for the detection of glucose in sweat and Buledi et al fabricated reusable nickel oxide/graphene oxide (GO)-based electrochemical sensors for the detection of linezolid drug in urine samples . Similarly, Boruah et al used human blood serum as sensing media for the detection of dopamine using nitrogen-doped GO …”

“…Viscosity and polarity have a similar effect as their increment promotes the RIR effect favoring AIE/AIEE, while the reverse effect is observed for an increase in temperature of the sensing media . Compared to other fluorescent sensors, AIE- or AIEE-based sensors achieved remarkable attention because of their simplistic mechanism, beneficial for the development of turn-on sensors, high detecting ability in an aqueous medium, etc . The reduced form of the GO process has unique fluorescence properties in the nanorange due to its specific band gap that falls in the semiconductor range .…”