Wearable Noninvasive Glucose Sensor Based on CuxO NFs/Cu NPs Nanocomposites

Abstract

Designing highly active material to fabricate a high-performance noninvasive wearable glucose sensor was of great importance for diabetes monitoring. In this work, we developed CuxO nanoflakes (NFs)/Cu nanoparticles (NPs) nanocomposites to serve as the sensing materials for noninvasive sweat-based wearable glucose sensors. We involve CuCl2 to enhance the oxidation of Cu NPs to generate Cu2O/CuO NFs on the surface. Due to more active sites endowed by the CuxO NFs, the as-prepared sample exhibited high sensitivity (779 μA mM−1 cm−2) for noninvasive wearable sweat sensing. Combined with a low detection limit (79.1 nM), high selectivity and the durability of bending and twisting, the CuxO NFs/Cu NPs-based sensor can detect the glucose level change of sweat in daily life. Such a high-performance wearable sensor fabricated by a convenient method provides a facile way to design copper oxide nanomaterials for noninvasive wearable glucose sensors.

Research Progress on Biomimetic Nanomaterials for Electrochemical Glucose Sensors

“…Metal oxides are also used in glucose detection and applied to sweat glucose. For example, Kang et al [ 104 ] designed and developed Cu x O nanosheets (NFs)/Cu nanoparticles (NPs) nanocomposites as sensitive materials for noninvasive sweat wearable glucose sensors, as shown in Figure 11 B. Because Cu x O NFs confers more active sites, the prepared materials exhibited high sensitivity (779 μA mM −1 cm −2 ) for noninvasive wearable sweat sensing.…”

“… Electrochemical sweat glucose sensors based on different biomimetic nanomaterials: ( A ) Pt/MXene [ 104 ] with permission (Copyright © 2023, American Chemical Society); ( B ) Cu 2 O NFs/Cu NPs with permission (Copyright © 2023, MDPI); ( C ) Ni–Co MOF nanosheet coated Au/PDMS film [ 7 ] with permission (Copyright © 2022, The Royal Society of Chemistry). …”

Electrochemical Fabrication of 2D CuO Nanosheets on Pt Foil as a Highly Sensitive Non‐Enzymatic Glucose Sensor

“…Currently, several low-cost transition metal oxides such as Fe 2 O 3 , [26][27] Mn x O x , [6,28] MoO 2 , [29] CdO, [30] NiO, [1][2][31][32] ZnO, [33] and CuO [25,[34][35][36][37] have been studied for use in non-enzymatic glucose sensors. Among all of these metal oxides, CuO has been widely explored as a catalytic material for different applications including semiconductors, supercapacitors, batteries, solar energy conversion, gas sensing devices, catalysis, biosensors, and transistors because it is a p-type semiconductor with a band gap of 1.2 eV, and it exhibits a low overpotential for electron exchange, excellent electrocatalytic activity, high active surface area, good chemical stability, and biocompatibility.…”

“…Additionally, CuO is non toxic, inexpensive, and abundant. [25,[35][36][37][38] The particle size and shape of materials significantly affect their electrocatalytic activity. [25] CuO nanomaterials of various shapes have been designed and studied for glucose sensing applications including nanospheres, [39] nanorods, [40] nanowires, [41] nanocubes, [42] nanosheets, [43][44] nanofibers, [45] nanoflowers [46][47] and octahedra.…”

“…Among all of these metal oxides, CuO has been widely explored as a catalytic material for different applications including semiconductors, supercapacitors, batteries, solar energy conversion, gas sensing devices, catalysis, biosensors, and transistors because it is a p‐type semiconductor with a band gap of 1.2 eV, and it exhibits a low overpotential for electron exchange, excellent electrocatalytic activity, high active surface area, good chemical stability, and biocompatibility. Additionally, CuO is non toxic, inexpensive, and abundant [25,35–38] …”