Non-enzymatic Glucose Research Articles

Development of a high-performance Cu–Ni decorated laser-induced graphene sensor for nonenzymatic glucose monitoring in sweat

Development of a high-performance Cu–Ni decorated laser-induced graphene sensor for nonenzymatic glucose monitoring in sweat

Computational Model-Assisted Development of a Nonenzymatic Fluorescent Glucose-Sensing Assay.

Deep-red fluorescence was implemented in this fully injectable, nonenzymatic glucose biosensor design to allow for better light penetration through the skin, particularly for darker skin tones. In this work, a novel method was developed to synthesize Cy5.5 labeled mannose conjugates (Cy5.5-mannobiose, Cy5.5-mannotriose, and Cy5.5-mannotetraose) to act as the fluorescent competing ligand in a competitive binding assay with the protein Concanavalin A acting as the recognition molecule. Using fluorescence anisotropy (FA) data, a computational model was developed to determine optimal concentration ratios of the assay components to allow for sensitive glucose measurements within the physiological range. The model was experimentally validated by measuring the glucose response via FA of the three Cy5.5-labeled mannose conjugates synthesized with Cy5.5-mannotetraose demonstrating the most sensitive response to glucose across the physiological range. The developed method may be broadly applied to a vast range of commercially available fluorescent dyes and opens up opportunities for glucose measurements using nonenzymatic assays.

A Wearable Electrochemical Sensor Based on Single-Atom Pt Anchored on Activated NiCo-LDH/Ti3C2Tx for Real-Time Monitoring of Glucose.

Wearable, noninvasive sweat sensors enable real-time monitoring of metabolites in human health management. However, the commercial enzyme-based and currently nonenzymatic glucose sensor represents sluggish glucose oxidation kinetics and a narrow sensing range. Rational design of sensitive materials is significant yet faces a huge challenge. Herein, we construct a single-atom Pt supported on NiCo-LDH/Ti3C2Tx heterostructures (Pt1-NiCo-LDH/Ti3C2Tx) as the nonenzymatic electrochemical glucose sensor sensitive materials for selective detection of glucose level in human sweat. The obtained Pt1-NiCo-LDH/Ti3C2Tx with improved structural stability and enhanced charge transfer efficiency shows a low oxidation peak potential of 0.49 V, high sensitivity of 506.6 μA mM-1 cm-2, a low detection limit of 0.035 μM, and long-term stability toward the glucose detection. The wearable sensor, coupled with a wireless transmission module and a signal processing chip, is used for real-time perspiration glucose monitoring during outdoor exercise. The result is comparable to that of high-performance liquid chromatography (HPLC). This research provides a new paradigm for designing a wearable nonenzymatic electrochemical glucose sensor, enabling noninvasive real-time monitoring of glucose concentrations in human sweat.

In-situ Electrochemical Synthesis of Ni/Ni(OH)2/Molecularly Imprinted Polymer Nanocomposite for High-Performance Glucose Detection

This study presents a novel non-enzymatic glucose sensor that synergistically combines the high catalytic activity of nickel hydroxide (Ni(OH)2) with the selective recognition of molecularly imprinted polymers (MIPs). The sensors were fabricated through an entirely in-situ synthesis directly on the electrode, comprising electrodeposition and oxidation of Ni/Ni(OH)2 nanoparticles and electropolymerization of a glucose-imprinted MIP layer using pyrrole and 3-aminophenyl boronic acid. The integrated MIP layer significantly enhanced selectivity against common interferents while amplifying glucose sensitivity. The resulting sensor demonstrated a high sensitivity of 1802 μA mM-1 cm-2 with a linear range from 0.04 to 2.6mM. Notably, the sensor exhibited remarkable stability, retaining 97.2% of its original sensitivity after 6 months of room-temperature storage. To extend the linear range, Nafion coatings at two concentrations were applied, achieving ranges up to 0.04 – 11.6mM with adjusted sensitivities. This innovative approach, leveraging MIPs to provide selectivity to electrocatalytic nanomaterials, offers a promising strategy for developing high-performance non-enzymatic sensors for glucose and other biomolecules in diabetes monitoring and beyond.

Duality application analysis of bismuth vanadate (BiVO4) as non-enzymatic glucose sensor and supercapacitor

Duality application analysis of bismuth vanadate (BiVO4) as non-enzymatic glucose sensor and supercapacitor

Fabrication and Potential Characterization of Silver‐Doped Zinc Oxide Glucose Biosensor

This work is devoted to studying and manufacturing a highly sensitive nonenzymatic glucose biosensing system of metal oxides via the sol–gel technique. The X‐ray diffraction patterns of all the prepared samples confirm that the samples present hexagonal crystal lattice structures of ZnO and Ag–ZnO nanoparticles. Ultraviolet (UV) analysis of all the samples is carried out to evaluate the absorption of silver in the UV region for electrical and chronoamperometric analysis. The transmittance of all the samples is observed, and the maximum transmittance is 11% for 4% AgZnO. Fourier transform infrared spectroscopy reveal the functional group stretching and vibration of the particles at different wavelength ranges. Scanning electron microsocpy analysis reveals the grain size and morphology of the samples, which decrease with increasing doping agent. Chronoamperometric analysis of all the samples reveals that the value increases with time for the 4% doped sample. The sensing response is also observed and is enhanced with increasing temperature for the 4% doped sample. The sensing response of the samples coated with carbon fiber electrodes is assessed from −0.2 to +0.5 V at a scan rate of 50 mV s−1.

Polymer organic framework-based ratiometric fluorescent probe for non-enzymatic glucose detection

Fluorescent pyrene-based polymer organic frameworks (POFs) PY-POFs were designed and synthesized by a facile solvothermal route for glucose detection, employing melamine, aromatic dialdehydes, 1-pyrenecarboxaldehyde, and phenylboronic acid as building blocks. The structure and photophysical properties of as-prepared POFs were systematically characterized via Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, N2 adsorption isotherms and fluorescence spectroscopy. The PY-POFs possessed intrinsic microporosity derived from extensively interlinked aminal structures, boasting specific surface areas reaching 192 m²/g, pore volumes extending to 0.8079 cm³/g, pore diameters of up to 17 nm, and an average particle dimension of ∼ 31 nm. In addition, the PY-POFs exhibited a dual-wavelength emission of pyrene excimer (λem = 472 nm) and monomer (λem = 382, 400, and 422 nm). When exposed to glucose, the former emission decreased while the latter increased, corresponding to the conformational transition of pyrene molecule from excimer to monomer. The non-enzymatic ratiometric fluorescent sensor displayed remarkable sensitivity towards glucose within 10−200 μM range, with a limit of detection (LOD) of 5.6 µM. Moreover, the glucose detection ability of PY-POFs was also in vivo demonstrated within zebrafish. Application of this sensor to real samples such as human saliva and DMEM biological matrix presented satisfactory results and good reproducibility. These results indicate that the fluorescent glucose sensor PY-POFs have broader prospects for utilization within biological studies.

α-MnO2 with a cryptomelane structure for the non-enzymatic glucose electrooxidation in a neutral medium

A high demand for non-enzymatic glucose sensors and continuous glucose monitoring systems encourages the development of stable and active catalysts for the enzymeless anodic oxidation of glucose in the neutral medium. In regard to this reaction, we analyze the prospects of alpha manganese dioxide with a cryptomelane structure synthesized via an aqueous chemical route. To provide various specific surface area, the hydrated α-MnO2 oxide is annealed in a wide temperature range from 60 to 700 °C. Furthermore, we investigate the influence of the oxide annealing temperature on the amount of crystal water, chemical composition, morphology, electrochemical recharging behavior, electrocatalytic activity and stability in the glucose oxidation carried out in an isotonic NaCl-based phosphate-buffered saline (pH 7.40). To solidly determine potentials of the irreversible cathodic dissolution of α-MnO2 as well as O2/Cl2 evolution on α-MnO2, a rotating ring-disk electrode is applied. For the most active α-MnO2 sample with the 100 μg cm−2geo loading the glucose oxidation current of ca. 40 μA cm−2geo after 1 h at +0.8 V (SCE) for 7 mM of glucose is achieved. The linear concentration dependence in a physiological glucose range (1–30 mM) with the sensitivity of ca. 17.8 μA mM−0.5 cm−2geo at 25 °C is observed. Finally, glucose selectivity of α-MnO2 in relation to fructose, galactose, xylose, ribose, urea, lactic acid, acetone, ascorbic acid and paracetamol is revealed.

ZnFe(PBA)@Ti3C2Tx nanohybrid-based highly sensitive non-enzymatic electrochemical sensor for the detection of glucose in human sweat

The ZnFe prussian blue analogue [ZnFe(PBA)] was infused with Ti3C2Tx (MXene) denoted as ZnFe(PBA)@Ti3C2Tx and was prepared by an in-situ sonication method to use as a non-enzymatic screen printed electrode sensor. The advantage of non-enzymatic sensors is their excellent sensitivity, rapid detection, low cost and simple design. The synthesized ZnFe(PBA)@Ti3C2Tx was characterized for its physical and chemical characterization by XRD, Raman, XPS, EDAX, and FESEM analysis. It possessed multiple functionalized layers and a cubic structure in the nanohybrid. Further, the sensor was investigated by using electroanalytical studies such as cyclic voltammetry and chronoamperometry analysis. The enhanced surface area with a cubic structure of ZnFe(PBA) and the excellent electrical response of Ti3C2 nanosheet support the advancement of a non-enzymatic electrochemical glucose sensor with improved sensitivity of 973.42 µA mM−1 cm−2 with the limit of detection (LOD) of 3.036 µM (S/N = 3) and linear detection range (LDR) from 0.01 to 1 mM.

Multifunctional MOF-5/Reduced Graphene Oxide Electrodes for Enhanced Nonenzymatic Glucose Detection and Supercapacitor Performance in Self-Powered Wearable Devices

Multifunctional MOF-5/Reduced Graphene Oxide Electrodes for Enhanced Nonenzymatic Glucose Detection and Supercapacitor Performance in Self-Powered Wearable Devices

In situ constructing p-n heterojunction NiCo-MOF/LDH with built-in electric field for wide response range of glucose sensing

The development of non-precious metal nanomaterial for glucose sensor with sensitive performance and broad detection range will be a great challenge. In this study, a p-n heterojunction catalyst (NiCo-MOF/LDH) is devised as an efficient electrocatalytic oxidation material for glucose detection in alkaline solutions. As an enzyme-free sensor of glucose, (NiCo-MOF/LDH) exhibits good electrochemical properties with high sensitivity of 27.76 μA mM−1 cm−2, a low detection limit of 8 µM at a signal-to-noise ratio of 3 and a wide linear range (40 μM-16 mM). The results indicate that the Mott-Schottky junction between NiCo-MOF and NiCo-LDH constructs the built-in electric field (BEF) and achieves the redistribution of surface charge. The local positive charge induced by the p-n junction allows the NiCo-MOF side to adsorb more OH−, and the local negative charge allows the NiCo-LDH side to adsorb glucose positively charged H, optimizing the adsorption reactants and key intermediates. At the same time, the sensor is successfully applied to the detection of glucose in actual sample samples. Hence, the p-n heterojunction NiCo-MOF/LDH provides a rational strategy for a non-enzymatic glucose sensing catalyst.

Fabrication of a novel non-enzymatic glucose sensor based on ruthenium supported by a combination of PBA nanocubes and MOF nanosheets

The development of novel catalysts with high catalytic activity is of high importance of electrochemical non-enzymatic glucose sensing. Herein, a sensitive non-enzymatic electrochemical sensor (Ru@NiCo-MOF/NiFe-PBA) has been synthesized using a fast, simple and eco-friendly method. The high stability of PBA and the large specific surface area (two-dimensional nanosheet structure) of MOF support the excellent electrochemical performance, while the incorporation of the highly active metal Ru enhances the electrochemical activity even more. The results reveal that the sensitivities of the sensor are 1070.77 and 487.62 μA mM−1 cm−2, corresponding to linear ranges of 0.01–0.67 mM and 0.67–5.07 mM, respectively. Meanwhile, the sensor has a low detection limit (0.446 μM) and a short response time (2 s), making it a strong candidate for non-enzymatic glucose sensors. The successful detection of glucose in saliva further demonstrates its potential for practical applications. Therefore, Ru@NiCo-MOF/NiFe-PBA will make an impact in the field of glucose monitoring and detection.

Study on the performance of MoS2/Au composites for non-enzymatic electrochemical glucose detection

Abstract Glucose concentration is considered an indicator for the diagnosis of diabetes, highlighting the importance of accurate glucose detection. Non-enzymatic electrochemical sensors have been extensively studied for glucose detection applications, with nanocomposites composed of molybdenum disulfide (MoS2) and gold nanoparticles (Au NPs) demonstrating high catalytic activity. In this study, a nanocomposite material composed of MoS2 and Au NPs (MoS2/Au) was synthesized and employed to construct a non-enzymatic electrochemical glucose biosensor. The detection limit of this sensor was explored, reaching as low as 1 mM. Additionally, compared to MoS2, the MoS2/Au nanocomposite exhibited a higher linear correlation coefficient and sensitivity, with a linear range of 1–25 mM and a sensitivity of 417.556 μA mM−1 cm−2. The sensor demonstrated excellent performance within the range of human blood glucose concentrations, showing potential for real-time monitoring and precise measurement of glucose levels. Furthermore, it exhibited good stability and reproducibility. These findings indicate the potential applications of MoS2/Au in biosensors and immunoassays.

Synergistic ZnO-NiO composites for superior Fiber-Shaped Non-Enzymatic glucose sensing

The rise in diabetes requires new glucose sensors, as traditional enzyme-based and planar electrodes are sensitive to the environment and hard to integrate into wearables. This study addresses these issues by developing a flexible, non-enzymatic glucose sensor using a co-sputtered ZnO: NiO (NZ) composite on PET fiber. This design enhances the tensile strength (60 mm at 3.2 kg.f) and conductance (0.23 S) of Cu-coated PET fiber, forming a durable sensing platform. The electrode’s enhanced electrochemical surface area (0.13 cm2) offers abundant active sites for glucose interaction, while the synergistic interface effect boosts ion and charge transport, improving glucose sensing. The sensor achieves high sensitivity (28.96 mA·cm−2·mM−1), fast response time (23 s), and a low detection limit (0.25 mM), while maintaining 78 % of its sensitivity after 500 bending cycles. These features, combined with good electrochemical stability—retaining 60 % of its initial performance after prolonged electrolyte exposure—mark a significant advancement in wearable glucose monitoring.

Ag@Au core–shell nanoparticles modified glassy carbon electrode synthesized by simple displacement reaction for non-enzymatic electrochemical glucose sensing

In this study, a new strategy was presented to enhance glucose sensor performance by modifying a glassy carbon electrode (GCE) with Ag@Au alloy nanoparticles. The synthesis process was designed with a simple replacement reaction to grow the gold layer onto the silver nanparticles to form a core–shell nanostructure. The resulting nanocomposite modified electrode exhibited superior electrocatalytic activity and stability in glucose sensing. Electrochemical measurements were undertaken to assess the performance of the as-synthesized Ag@Au/GCE. The Ag@Au core–shell nanoparticles modified GCE exhibited outstanding catalytic activity towards glucose detection, resulting in a high current response and a robust linear relationship between concentrations (10 μM–10 mM); the detection limit was remarkably low, at 0.04 μM. This sensor demonstrated a wide linear range, low detection limit, and high levels of selectivity and stability, rendering it suitable for accurate glucose quantification in biological samples.

Electrochemical non-enzymatic glucose biosensors based on Au-thiol-linked molecular architectures

In this work, an electrochemical non-enzymatic glucose sensor consisting of di-methanethiol-grafted poly (3,4-propylenedioxythiophene), gold nanoparticles (Au NPs), and reduced graphene oxide (rGO) was synthesized by a one-step method through Au-S chemisorption. The structure and morphology of the as-prepared poly (ProDOT-(MeSH)2)/Au/rGO composite were characterized by FT-IR, XRD, EDX, TEM, SEM, and XPS, and the electrochemical performance of the composite was investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) on glassy carbon electrode (GCE). The results show that because of the hydrogen bond interaction between the thiol group on the polymer units and the functional groups on GO, poly (ProDOT-(MeSH)2)/Au/rGO was successfully prepared. In addition, due to the unique morphological structure of the composite and the ability to absorb glucose molecules through hydrogen bonds, the poly(ProDOT-(MeSH)2)/Au/rGO electrode possesses excellent selectivity and unique sensitivity (46.13 μA mM−1 cm−2) for sensing glucose in the linear range of 0.04–16.0 mM with a detection limit of (S/N = 3) 0.01. This paper demonstrates that the poly(ProDOT-(MeSH)2)/Au/rGO composite holds great promise for application as a new glucose sensor in life science.

High-performance ZnO:CuO composite-based fiber-shaped electrode for non-enzymatic glucose sensing in biological fluids

The growing diabetes epidemic necessitates new glucose sensors, as traditional enzyme-based and planar electrodes face limitations in environmental stability and seamless integration into wearable technology. This research tackles these issues by designing a flexible, enzyme-free glucose sensor utilizing a co-deposited ZnO:CuO (CZ) composite on PET monofilament. This approach improves the tensile strength (55 mm at 2.7 kg.f) and electrical conductance (0.32 S), of the Ni-coated PET fiber, resulting in a strong and reliable sensing platform. The electrode's enlarged electrochemical surface area (0.11 cm2), offer a high density of active sites for glucose interaction, and the synergistic interface significantly enhances both ion and charge mobility. This results in exceptional sensitivity (35.05 mA.cm−2.mM−1), a rapid response (24 s), and a low detection limit (0.15 mM). Durability tests demonstrate that the sensor retains 80% of its sensitivity after 500 bending cycles, making it well-suited for wearable applications. Furthermore, the sensor accurately detects glucose in biological samples, such as saliva, highlighting its potential for non-invasive, real-time glucose monitoring in wearable healthcare systems.

A Study on Cu Decorated Anodic TiO2 Nanotubes for Non-Enzymatic Glucose Sensing and Photoelectrochemical Water Splitting Application

Free-standing, surface-modified TiO2 nanotubes(TNTs) decorated with copper nanostructures have been extensively studied as promising materials for their application in biosensing and photo-electrochemical splitting of water. Here, the TNTs are prepared by electrochemical anodization followed by modification with copper nanostructures via UV-assisted photo-reduction technique. Field-emission scanning electron microscopy and X-ray diffraction studies confirmed the structural and morphological properties of the TNTs, along with their tubular architecture and mixed-phase composition of Anatase-Rutile. Energy-dispersive spectroscopic analysis verified the successful deposition of copper. Diffuse reflectance spectroscopy revealed an electronic band gap of 3.2 eV. The copper-modified TNTs showed an enhanced sensitivity in the sensing of glucose to the tune of 0.52 mA mM−1 cm−2 with a high linear range of 0.5 to 7 mM and showed superior selectivity against interferents. It was found that the modified TNTs exhibited a higher photocurrent response of 1.09 mA cm−2 compared with pristine TNTs (0.69 mA cm−2). These findings indicate the promising potential of copper-modified TNTs for continuous glucose monitoring and photo-electrochemical applications.

Optimization and Characteristics of Multimodal Binder on Polymer Nanocomposite for Lightweight Applications

The process of selecting binders is complex because it requires finding a balance between improving material performance and reducing environmental impact. This involves challenges such as achieving nanoparticle dispersion, optimizing binder compatibility, and addressing environmental concerns. The main objective of this research on use the multimodal binder optimization characterization model (M-MBOCM) analysis to understand the intricate relationship between metal oxide nanoparticles, polymer matrices, and binders. These specialized nanocomposites have a wide range of potential applications. By intelligently selecting Scanning Characterization binders (SCB), industries can enhance material properties to meet specific requirements. This applies across various fields, from high-capacity energy storage devices to lightweight structural materials and smart sensors. This research involves analyzing metal oxide nanoparticle mage polymer nanocomposites with aqueous and nonaqueous binders in manganese dioxide-based cathodes (M-BC), hybrid supercapacitors (HS), and non-enzymatic glucose sensors (NEGS). The significance of M-BC in the present investigation results is based on advanced M-MBOCM and SCB techniques. The performance analysis ratio exceeds 95%, which is higher than the reported results for M-BC, HS, and NEGS. The scalability analysis ratio for M-MBOCM and SCM is observed to be higher than others, recorded at 93% and 88% respectively. These findings demonstrate the potential for enhanced nanocomposite materials in practical applications (lightweight) and drive their development.

Bioflocculant polymer reduced CuO/NiO binary transition metal oxide nanocomposite: Application as an effective non-enzymatic glucose sensor

A bimetallic copper oxide/nickel oxide nanocomposite (CuO/NiO NCs) was synthesized via direct carbonization method by using microbial polymer as reducing agent. This nanocomposite was employed as a viable non-enzymatic electrocatalyst in the glucose detection. It was completely characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopic (EDX) methods and revealed the obtained porous nanoflower morphology with particle sizes of 100–200 nm in a monoclinic face-centered cubic crystalline structure. FT-IR spectra confirmed the presence of functional groups and the purity of the nanocomposite. Electrocatalytic performance for glucose oxidation was evaluated through cyclic voltammetric (CV) and amperometric i-t techniques. The observation demonstrated that the CuO/NiO NCs exhibited a remarkable electro-oxidation activity against glucose, attributed to the synergistic effects of the bimetallic components. As an electrode surface modifier, the CuO/NiO NCs facilitated an enhanced glucose oxidation over a linear range of 1–9 mM via CV, while amperometric i-t measurements achieved a detection range from 0.04 μM to 4.86 mM in a 0.1 M NaOH (pH ∼ 13) electrolyte solution. These eco-friendly and in-expensive nanoflowers displayed excellent selectivity, stability, and reproducibility, underscoring their potential in diabetes monitoring and the subsequent scientific analysis.