In situ fabrication of CuO nanowire film for high-sensitive ascorbic acid recognition

Electrochemical detection of ascorbic acid in artificial sweat using a flexible alginate/CuO-modified electrode

“…Fabrication simplicity is considered based on the number of processing steps, duration, temperature, and applied voltages or currents (− − = very difficult; − = difficult; + = easy; ++ = very easy). SCE , saturated calomel electrode Sensing material Working potential (V) LOD (μM) Sensitivity Linear range (μM) Fabrication simplicity Carbon nanoplatelets derived from ground cherry husks [ 24 ] 0.026 vs. Ag/AgCl 1.09 0.20863 μA μM −1 cm −2 10–3570 + 3-layer sandwich of N-doped graphene, Ag NPs, and polyaniline [ 25 ] 1.2 vs. Ag/AgCl 8 28,900–280,500 μM μA −1 10–11.460 − CuO nanowires derived from a self-assembled Cu-Fe nanocube [ 40 ] 0.1 vs. Ag/AgCl 0.5 0.07857 μA μM −1 cm −2 20–400 − − CuO nanoflowers on 3D graphene foam [ 41 ] 0.2 vs. (SCE) 0.43 2.06 μA μM 1 cm −2 20–200 − − Graphene/copper/phthalocyanine/polyaniline nanocomposites [ 54 ] 0.1 vs. Ag/AgCl 0.063 24,460 μA μM −1 0.5–120 − − Redox-active molybdophosphate film [ 26 ] 0.4 vs. Ag/AgCl 0.04 0.21021 μA μM −1 cm −2 1–1500 − Reduced graphene oxide/Fe 3 O 4 nanoparticles/hydroxypropyl-β-cyclodextrin nanocomposite [ 37 ] − 0.044 vs. SCE 5 0.01 μA μM −1 15–360 + Graphene oxide/multi-walled carbon nanotubes/Au nanorods [ 27 ] 0.036 vs. Ag/AgCl 0.85 7.61 μA μM −1 cm −2 0.001–0.5 and 1–8000 + …”

“…Ascorbic acid is known to be a reducing agent for nanostructured copper, being used for NP preparation [39], and as aforementioned, it has a preference for electron donation to the copper center of the ascorbate oxidase enzyme. This property can be exploited for its determination using simpler copper-based nonenzymatic materials, as demonstrated using CuO (copper oxide) nanowires synthesized on Cu foils by a thermal oxidation process at 350°C for 100 min [40], or with 3D graphene/ CuO nanoflowers fabricated by copper electrodeposition on a graphene structure grown by chemical vapor deposition (CVD) on a nickel foam that was later etched [41].…”

Single-Step Modified Electrodes for Vitamin C Monitoring in Sweat

“…Other works exist with good sensitivity at micromolar concentrations and without enzymes, but require either working at a higher potential (Salahandish et al, 2019) or a more difficult and longer fabrication process involving several steps (Pakapongpan et al, 2014), high temperatures (higher cost) (Li et al, 2017;You et al, 2019), or complex/costly equipment (Ma et al, 2014). Our proposed approach performs the measurements in both imidazole (neutral pH) and artificial perspiration solution (acidic) with a sensor response at nearly zero voltage and in the lower micromolar range, convenient for direct detection in human sweat.…”

“…Ascorbic acid is known to be a reducing agent for nanostructured copper, being used for NPs preparation (Cheng et al, 2006). This property can be exploited for its detection, as demonstrated using CuO (copper oxide) nanowires synthesized on Cu foils by a thermal oxidation process at 350 °C for 100 min (You et al, 2019), or with 3D graphene/CuO nanoflowers fabricated by copper electrodeposition on a graphene structure grown by chemical vapor deposition (CVD) on a nickel foam that was later etched (Ma et al, 2014). Ideally, the cost and duration of the fabrication process should be minimized by avoiding of complex equipment and energy consuming steps and the sensor should operate at a low voltage and at room temperature.…”

A low cost flexible photocatalyst based on silver decorated Cu2O nanowires

“…The second method is the chemical synthesis in which hydrothermal method is used starting from copper acetate monohydrate at around 180 °C [22,23]. Third one is the electrochemical anodizing method where the anode material is a copper foil and it is anodized to give the nanowires in strong alkali conditions [24]. Among those three methods, electrochemical anodizing method has the least benefited method in the literature.…”