High-performance Non-enzymatic Glucose Research Articles

RETRACTED: Hatshan et al. Advanced Binder-Free Electrode Based on CuCo2O4 Nanowires Coated with Polypyrrole Layer as a High-Performance Nonenzymatic Glucose Sensing Platform. Coatings 2021, 11, 1462

The Coatings Editorial Office retracts the article entitled “Advanced Binder-Free Electrode Based on CuCo2O4 Nanowires Coated with a Polypyrrole Layer as a High-Performance Nonenzymatic Glucose Sensing Platform” [...]

Integrating Cu/CuxO ternary nanocomposites with multi-walled carbon nanotubes enabling a high-performance nonenzymatic amperometric glucose sensor

We developed a new nonenzymatic amperometric glucose sensor by integrating a ternary nanocomposite, Cu/Cu2O/CuO (Cu/CuxO), with multi-wall carbon nanotubes (Cu/CuxO@MWCNTs) as the electrocatalyst. The Cu/CuxO@MWCNTs nanocomposite is prepared via an electroless plating process followed by thermal treatment. The constructed nanocomposites are systematically characterized with a transmission electron microscope, an X-ray diffractometer, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and electrochemical impedance spectroscopy, respectively. The Cu/CuxO@MWCNTs nanocomposites-modified glassy carbon electrodes exhibit high electrocatalytic activity toward glucose electrooxidation under alkaline conditions. The efficient electrocatalytic activity of Cu/CuxO@MWCNTs for glucose electrooxidation is utilized for glucose detection using Cu/CuxO@MWCNTs-modified glassy carbon electrodes. The Cu/CuxO@MWCNTs-modified electrode displays an excellent sensing performance within a wide analyte concentration from 0.005-6,000 M (low detection limit is calculated to be 0.003 μM) with superior stability, selectivity, repeatability, and reproductivity. This as-prepared electrochemical sensor is successfully applied to selective glucose detection with satisfactory results.

MOF-based Sensing Materials for Non-enzymatic Glucose Sensors

<p>Diabetes mellitus is one of the common chronic diseases, seriously threating to human health. The continuous monitoring of blood glucose concentration can effectively prevent diabetic diseases. The sensing performance of glucose non-enzymatic sensors is mainly determined by working electrode materials. Metal–organic frameworks (MOFs) are recognized as promising candidate for glucose sensor application, due to its large surface areas, ordered porous structure and nearly infinite designability. In this review, the sensing performance, research progress and future challenge of non-enzymatic glucose sensors based on MOF-based materials in recent years are presented. We hope that this review would provide valuable technology guidance for high performance non-enzymatic glucose sensors based on MOFs.</p>

In Situ Exfoliation Growth Strategy Realizing Controlled Synthesis of 3D to 2D MOF Materials as High-Performance Electrochemical Biosensors.

Two-dimensional (2D) metal-organic framework (MOF) nanosheets with large surface area, ultrathin thickness, and highly accessible active sites have attracted great research attention. Developing efficient approaches to realize the controllable synthesis of well-defined 2D MOFs with a specific composition and morphology is critical. However, it is still a significant challenge to construct thin and uniform 2D MOF nanosheets and resolve the reagglomeration as well as poor stability of target 2D MOF products. Here, an "in situ exfoliation growth" strategy is proposed, where a one-step synthetic process can realize the successful fabrication of PBA/MIL-53(NiFe)/NF nanosheets on the surface of nickel foam (NF) via in situ conversion and exfoliation growth strategies. The PBA/MIL-53(NiFe)/NF nanosheets combine the individual advantages of MOFs, Prussian blue analogues (PBAs), and 2D materials. As expected, the resulting PBA/MIL-53(NiFe)/NF as a glucose electrode exhibits an extremely high sensitivity of 25.74 mA mM-1 cm-2 in a very wide concentration range of 180 nM to 4.8 μM. The present exciting work provides a simple and effective strategy for the construction of high-performance nonenzymatic glucose electrochemical biosensors.

Efficient synthesis of Ni3S2 nanoflowers supported on S, N-codoped carbon flakes via molten NaCl template for High-Performance non-enzymatic glucose detection catalysts

Ni3S2 nanoflowers supported on S, N-codoped carbon flakes (Ni3S2/SNCF) are successfully synthesized via a facile pyrolysis method with the assistant of a molten NaCl template. This unique approach not only facilitates the formation of the desired nanoflower and flake structure but also promotes the synthesis of pure Ni3S2, crucial for its non-enzymatic glucose detection performance. L-cysteine served as the source of nitrogen, sulfur, and carbon. The distinctive structure significantly enhanced the catalytic activity for glucose oxidation by exposing active sites, modifying electronic environment, and improving conductivity. Ni3S2/SNCF exhibited remarkable glucose sensing: high sensitivity (1704 μA mM−1 cm−2), low detection limit (1.1 μM, S/N = 3), wide linear range (3.7 μM-1.7 mM), and excellent resistance to interference, reproducibility, and long-time stability. Furthermore, Ni3S2/SNCF showed promising potential for non-enzymatic glucose detection in artificial sweat. This study presents a general methodology for the rational design and controlled fabrication of electrocatalysts with similar structures.

Sulfur-doped Co(OH)2 nanosheets with abundant oxygen vacancies for high-performance non-enzymatic glucose sensing

The development of high-performance materials for electrochemical non-enzymatic glucose sensing is crucial for diabetes detection and management. This study presents a facile approach for synthesizing sulfur-doped Co(OH)2 nanosheets with abundant oxygen vacancies, enhancing glucose sensing capabilities. Initially, ultrathin Co(OH)2 nanosheets are synthesized via a dissolution-recrystallization process, facilitated by l-lysine during hydrothermal synthesis. Subsequently, sulfur-doped Co(OH)2 nanosheets with oxygen vacancies (B-S-Co(OH)2) are produced through a two-step modification process using Na2S and NaBH4. The resulting B-S-Co(OH)2 exhibits high specific surface area, numerous oxygen vacancies, and rapid electron transfer, contributing to increased electrochemical activity. Electrochemical measurements, conducted with a glassy carbon rotating disk electrode (RDE), indicate low charge transfer barriers and enhanced redox properties. Consequently, B-S-Co(OH)2 nanosheets demonstrate superior glucose sensing performances, characterized by rapid response, high sensitivity (1.044 mA·mM–1·cm–2), broad linear range (0.01–1.4 mM and 1.6–3.6 mM), low detection limit (2.4 µM), and excellent long-term stability. This study offers an effective method for modifying the electronic structure and charge transfer properties of Co(OH)2 through surface modification, thereby advancing non-enzymatic glucose sensing capabilities.

Electrospun Manganese-Based Metal-Organic Frameworks for MnOx Nanostructures Embedded in Carbon Nanofibers as a High-Performance Nonenzymatic Glucose Sensor.

Material-specific electrocatalytic activity and electrode design are essential factors in evaluating the performance of electrochemical sensors. Herein, the technique described involves electrospinning manganese-based metal-organic frameworks (Mn-MOFs) to develop MnOx nanostructures embedded in carbon nanofibers. The resulting structure features an electrocatalytic material for an enzyme-free glucose sensor. The elemental composition, morphology, and microstructure of the fabricated electrodes materials were characterized by using energy-dispersive X-ray spectroscopy (EDX), field-emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). Cyclic voltammetry (CV) and amperometric i-t (current-time) techniques are characteristically employed to assess the electrochemical performance of materials. The MOF MnOx-CNFs nanostructures significantly improve detection performance for nonenzymatic amperometric glucose sensors, including a broad linear range (0 mM to 9.1 mM), high sensitivity (4080.6 μA mM-1 cm-2), a low detection limit (0.3 μM, S/N = 3), acceptable selectivity, outstanding reproducibility, and stability. The strategy of metal and metal oxide-integrated CNF nanostructures based on MOFs opens interesting possibilities for the development of high-performance electrochemical sensors.

Direct co-deposition of binder-free Cu-biochar-based nonenzymatic disposable sensing element for electrochemical glucose detection

This work is the first attempt to incorporate biochar on a pencil graphite electrode via one-step electrodeposition as a rational route for refining a copper-based biosensor for a high-performance nonenzymatic electrochemical glucose sensor. Biochar undecorated electrode counterpart was also fabricated for comparison. The cyclic voltammetry graph showed that co-deposition with biochar enhanced the electrocatalytic activity toward glucose oxidation in an alkaline medium. The surface morphology of the copper-biochar hybrid coating demonstrated an attractive three-dimensional structure that had not been reported in the literature. The results indicated that the supplied extending surface area due to biochar modification was the controlling factor for the improved electrochemical reactivity for glucose sensing. The amperometric analysis at an optimum potential of +0.70 V showed linear detection ranges from 0.8 µM to 1 mM and from 1 mM to 5 mM, and good characteristics, such as high sensitivity (6214.4 µA mM−1 cm–2), low limit of detection (0.8 µM), a fast response time (less than 2 s), and excellent anti-interference capability toward the oxidation of glucose. The cost-effective and facile fabrication suggests that the prepared glucose-sensing element can be potentially adapted for construction as a disposable.

Hierarchically porous cellulose nanofibril aerogel decorated with polypyrrole and nickel-cobalt layered double hydroxide for high-performance nonenzymatic glucose sensors

Hierarchically porous cellulose nanofibril aerogel decorated with polypyrrole and nickel-cobalt layered double hydroxide for high-performance nonenzymatic glucose sensors

Effect of Carbon Layer Thickness on the Electrocatalytic Oxidation of Glucose in a Ni/BDD Composite Electrode.

High-performance non-enzymatic glucose sensor composite electrodes were prepared by loading Ni onto a boron-doped diamond (BDD) film surface through a thermal catalytic etching method. A carbon precipitate with a desired thickness could be formed on the Ni/BDD composite electrode surface by tuning the processing conditions. A systematic study regarding the influence of the precipitated carbon layer thickness on the electrocatalytic oxidation of glucose was conducted. While an oxygen plasma was used to etch the precipitated carbon, Ni/BDD-based composite electrodes with the precipitated carbon layers of different thicknesses could be obtained by controlling the oxygen plasma power. These Ni/BDD electrodes were characterized by SEM microscopies, Raman and XPS spectroscopies, and electrochemical tests. The results showed that the carbon layer thickness exerted a significant impact on the resulting electrocatalytic performance. The electrode etched under 200 W power exhibited the best performance, followed by the untreated electrode and the electrode etched under 400 W power with the worst performance. Specifically, the electrode etched under 200 W was demonstrated to possess the highest sensitivity of 1443.75 μA cm-2 mM-1 and the lowest detection limit of 0.5 μM.

High-performance non-enzymatic glucose sensor based on Co3O4/rGO nanohybrid

High-performance non-enzymatic glucose sensor based on Co3O4/rGO nanohybrid

High-performance catalytic electrode for glucose sensor fabricated by one-step selective oxidation of brass compositions

In this study, three-dimensional nanostructured electrodes were synthesized by one-step electrochemical anodizing of the brass. Composites based on different oxides/hydroxides including ZnO, Cu2O, Cu(OH)2, and CuO are selectively prepared by potential modulation for the first time. With the increase of potential, the nano-oxide transforms from granular morphology into uniformly distributed nanosheet clusters, and the size of the nano-sheet decreases gradually with the increase of potential, finally, the double-layer nanosheet structure is formed. Attributed to the finely regulated composition and nanostructure, high-performance non-enzymatic glucose sensor electrodes are developed, which can exhibit prominent sensitivity for glucose catalytic up to 2817 μA·mM−1·cm−2 with a response time within 3 s and outstanding selectivity. This pioneering work not only offers a promising strategy for the rational construction of high-performance glucose catalytic nanostructured electrodes, but also provides a fresh pathway for the selective oxidation of alloys to form functional materials that meet practical needs.

Controllable morphology engineering of Cu2O nanoparticles for non-enzymatic glucose sensing

The controllable morphology engineering of active electrode materials is an effective strategy to obtain high performance non-enzymatic glucose sensing. Herein, different morphologic cuprous oxide (Cu2O nanospheres, nanocubes and microcubes) were controllably prepared by wet-chemistry precipitation technique through adjusting the OH– concentration. The growth and evolution mechanism of Cu2O at different OH– concentrations were extensively studied. Electrochemical testing revealed that Cu2O nanospheres had the highest sensitivity of 1438 μA mM−1 cm−2 and the lowest detection limit of 0.17 μM (S/N = 3), making them the best choice for glucose sensing. Additionally, the glucose detection range spanned two orders of concentration magnitude (0.5 μM ∼ 1.332 mM and 1.332 mM ∼ 3.832 mM), and the sensor displayed excellent anti-interference ability, reproducibility, and long-term stability. The electrode material also performed well in detecting glucose in real serum samples, indicating its practical applicability as a non-enzymatic sensor.

RGO decorated N-doped NiCo2O4 hollow microspheres onto activated carbon cloth for high-performance non-enzymatic electrochemical glucose detection

This paper reports the first effective fabrication of a high-performance non-enzymatic glucose sensor based on activated carbon cloth (ACC) coated with reduced graphene oxide (RGO) decorated N-doped urchin-like nickel cobaltite (NiCo2O4) hollow microspheres. Hierarchically mesoporous N-doped NiCo2O4 hollow microspheres were synthesized using a facile solvothermal method, followed by thermal treatment in a nitrogen (N2) atmosphere. Subsequently, they were hydrothermally decorated with RGO nanoflakes. The resulting composite was dip-coated onto ACC, and its electrochemical and glucose sensing performances were investigated using electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and chronoamperometric measurements in a three-electrode system. The composite electrode sensor demonstrates admirable sensitivity (6122 μM mM−1 cm−2) with an ultralow detection limit (5 nM, S/N = 3), and it performs well within a substantial linear range (0.5–1.450 mM). Additionally, it exhibits good long-term response stability and outstanding anti-interference performance. These outstanding results can be attributed to the synergistic effects of the highly electrically conductive ACC with multiple channels, the enhanced catalytic activity of highly porous N-doped NiCo2O4 hollow microspheres, and the large electroactive sites provided by its well-developed hierarchical nanostructure and RGO nanoflakes. The findings highlight the enormous potential of the ACC/N-doped NiCo2O4@RGO electrode for non-enzymatic glucose sensing.

Binary (α–β) NiS/PANI Nanorods with Highly Efficient Catalytic Activity in Nonenzymatic Glucose Fuel Cells and Sensors

Improving the efficiency of glucose oxidation reaction (GOR) is extremely important to build high performance nonenzymatic glucose sensors and fuel cells. In this work, we designed a novel binary ([Formula: see text]–[Formula: see text] NiS/PANI nanorods electrocatalyst with polyaniline (PANI) as the substrates and binary ([Formula: see text]–[Formula: see text] NiS nanoparticles dispersing on the PANI nanorods. The as-prepared NiS/PANI nanorods were characterized by XRD, XPS and SEM. The electrochemical performance of NiS/PANI nanorods was evaluated by cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscopy, which showed highly improved catalytic efficiency for GOR. When used as anodic catalysts in nonenzymatic glucose fuel cells, NiS/PANI nanorods displayed much higher power density of 1343.39 [Formula: see text] with an open circuit voltage of 0.84 V. NiS/PANI/NiS nanorods also presented excellent nonenzymatic sensing performance for glucose detection including a wide sensitivity of 682.21 [Formula: see text] (10–9000 [Formula: see text]M) and the low detection limit of 3.33 [Formula: see text]M ([Formula: see text]). The obviously improved electrochemical properties of NiS/PANI/NiS nanorods for GOR may be due to the synergistic effect of binary ([Formula: see text]–[Formula: see text] NiS and PANI nanorods.

Synthesis of CuO Nanrods Using Chemical Bath Deposition for a Nonenzymatic Glucose Biosensor

In the present research, CuO NRs are produced on Indium Tin Oxide (ITO) using (CBD) growth process, and their electrochemical characteristics for glucose biosensors are studied. A field emission scanning electron microscope, x-ray diffractometer, energy dispersive x-ray, and UV-VIS spectroscopy were used to examine the morphology and crystallinity of a CuO film. The synthesized CuO film displays a monoclinic phase with average crystallite sizes of around (18–25) nm. CuO is composed of NRs aggregating together to construct flower and flower bud-like shape structures with a diameter between (20-80) nm and a thickness of the CuO film is about (158.5-285.7) nm. The energy gap of CuO NRs was 2.55 eV. The I-V characteristics of the biosensors were measured and evaluated at various glucose concentrations to determine their sensitivity. The electrocatalytic performance of the CuO for the detection of glucose was outstanding. With a very low limit of detection (LOD) of 0.45 μM and a sensitivity of 799 µA cm-2 Mm-1, the electrode attained a wide linear range from 0.5 to 2 mM. This result highlights the sensor's tremendous potential as a high-performance non-enzymatic glucose sensor that makes use of an original, cost-effective, and straightforward sensor design.

High-performance enzyme-free glucose and hydrogen peroxide sensors based on bimetallic AuCu nanoparticles coupled with multi-walled carbon nanotubes

Interest in designing and manufacturing non-enzymatic biosensors is growing which stimulates the increased research efforts to explore innovative nanocomposites with highly catalytic activity. Here, the development of high-performance non-enzymatic glucose and hydrogen peroxide (H2O2) sensors based on bimetallic AuCu nanoparticles coupled with multi-walled carbon nanotubes (AuCu@MWCNTs) was achieved in this work. They were investigated by the cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and chronoamperometry (CA) methods separately. Benefiting from the synergistic effects of AuCu@MWCNTs, the proposed biosensors exhibited excellent performance such as low detection limits (1.3 nM for glucose, 0.1 nM for H2O2), broad linear ranges (8 nM-60 mM for glucose, 1 nM-4 mM for H2O2) and high sensitivities (362.3 μA·mM−1·cm−2 for glucose, 1335 μA·mM−1·cm−2 for H2O2). Besides, the AuCu@MWCNTs based electrodes provided excellent stability, repeatability and reproducibility. Based on the outstanding performance, they exhibited good reliability and accuracy in the detection of glucose in goat serum samples and real-time monitoring of H2O2 released by living cells. The present work suggests that the fabricated biosensor holds great potential for non-enzymatic glucose determination and real-time quantitative detection of H2O2 in biomedical applications.

Au Nanoparticles-Modified NiCo₂O₄ Nanowires-Supporting Co₃O₄ Dodecahedron as High-Performance Nonenzymatic Glucose Sensor

A hierarchically nanostructured active material composed of nanoparticles, microsized dodecahedron, and nanowires (NWs) has been successfully fabricated and used for glucose oxidation, in which the NiCo2O4 NWs were grown in situ on the carbon paper (CP) and used for supporting the zeolitic imidazolate framework (ZIF-67)-derived Co3O4 dodecahedron, with the Au nanoparticles (Au-Np) being further electrodeposited on their surface (Au-Np/Co3O4/NiCo2O4 NWs/CP). The NWs effectively avoid the agglomeration of Co3O4, thus providing greater surface area for loading the Au nanoparticles. The introduction of Au can decrease the oxidation potential and enhance the catalytic current, which is beneficial for the electrocatalytic oxidation of glucose. The Au-Np/Co3O4/NiCo2O4 NWs/CP-based nonenzymatic glucose sensor exhibits good sensing performance, including high sensitivity of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$15.3~\mu \text{A}/\mu \text{M}$ </tex-math></inline-formula> /cm2, outstanding response/recovery times of 2.5/4.0 s (toward 180- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{M}$ </tex-math></inline-formula> glucose), good reproducibility, and excellent selectivity. Therefore, constructing a hierarchical nanocomposite is a promising strategy to develop a nonenzymatic electrochemical glucose sensor.

Screen-Printing Preparation of High-Performance Nonenzymatic Glucose Sensors Based on Co3O4 Nanoparticles-Embedded N-Doped Laser-Induced Graphene

Screen-Printing Preparation of High-Performance Nonenzymatic Glucose Sensors Based on Co₃O₄ Nanoparticles-Embedded N-Doped Laser-Induced Graphene

High-performance non-enzymatic glucose sensing on nanocomposite electrocatalysts of nickel phthalocyanine nanorods and nitrogen doped-reduced graphene oxide nanosheets

Highly stable and efficient electrocatalytic materials are essential for developing high-performance non-enzymatic fourth-generation glucose biosensors. In this regard, hybrid materials incorporating metallophthalocyanines and carbon-based nanostructures are particularly interesting. A nanocomposite of nitrogen-doped reduced graphene oxide nanosheets and nickel phthalocyanine nanorods (N-rGONs|NiPcNRs) was prepared. N-rGONs|NiPcNRs were highly efficient and stable electrocatalysts for non-enzymatic d-glucose electrooxidation in alkaline media. Spectroscopic, microscopic, and electrochemical methods were used to characterize and evaluate the electrocatalytic performance of the N-rGONs|NiPcNRs. The remarkable electrocatalytic activity of N-rGONs|NiPcNRs originated from the in-situ transformation and formation of polymeric O-Ni-O oxo-bridge in alkaline electrolyte and the excellent electroconductivity of the N-rGONs. The N-rGONs|NiPcNRs with the optimum ratio of NiPcNRs to N-rGONs presented an efficient formation of the Ni-O-Ni oxo-bridge and d-glucose electrooxidation compared to N-rGONs and NiPcNRs alone. Thus, the fabricated GCE|N-rGONs|NiPcNRs glucose sensor showed an excellent analytical performance with a high sensitivity of 1458 µA.mM−1.cm−2 and a detection limit of 1.43 µM (S/N = 3) using cyclic voltammetry. For online glucose detection using chronoamperometry, a sensitivity of 358.9 µA.mM−1.cm−2 with a detection limit of 5.0 µM (the lowest concentration that could be discriminated from the buffer using GCE|N-rGONs|NiPcNRs) and a fast response time of 0.80 s was obtained. The high sensitivity of CV (1458 µA.mM−1.cm−2) allowed for lower limits of detection (1.34 µM). The fabricated sensor was successfully applied for the determination of d-glucose levels in serum samples, demonstrating its potential for monitoring glucose levels in diabetes patients.