Non-enzymatic Glucose Sensor Research Articles

Diabetes Management by Fourth-Generation Glucose Sensors Based on Lemon-Extract-Supported CuO Nanoporous Materials.

Diabetes is a major worldwide health issue, impacting millions of people around the globe and putting pressure on healthcare systems. Accurate detection of glucose is critical for efficient diabetes care, because it allows for prompt action to control blood sugar levels and avoid problems. Reliable glucose-sensing devices provide individuals with real-time information, allowing them to make more educated food, medicine, and lifestyle decisions. The progress of glucose sensing holds the key to increasing the quality of life for diabetics and lowering the burden of this prevalent condition. The present investigation addresses the synthesis of a CuO@lemon-extract nanoporous material using the sol-gel process. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to analyze the morphological properties of the composite, which revealed a homogeneous integration of CuO nanoparticles (NPs) on the surface of the matrix. The existence of primarily oxidized copper species, especially CuO, was confirmed by X-ray diffraction spectroscopy (XRD) investigation in combination with energy-dispersive X-ray (EDX) spectroscopy. The CuO@lemon-extract-modified glassy carbon electrode (CuO@lemon-extract GCE) performed well in non-enzymatic electrochemical sensing applications such as differential pulse voltammetry (DPV) and amperometric glucose detection. The electrode achieved a notable sensitivity of 3293 µA mM-1 cm-2 after careful adjustment, with a noticeable detection limit of 0.01 µM (signal-to-noise ratio of 3). The operational range of the electrode was 0.01 µM to 0.2 µM, with potential applied of 0.53 V vs. Ag/AgCl. These findings underscore the CuO@lemon-extract GCE's promise as a robust and reliable platform for electrochemical glucose sensing, promising advances in non-enzymatic glucose sensing (NEGS) techniques.

Development of TiO2-Based nanocomposite film for colorimetric detection of glucose

This study proposes the development of a colorimetric non-enzymatic glucose sensor based on TiO2/I2/CMC (TIC) nanocomposite film. A solution-cast approach was employed for the synthesis of nanocomposite film. The structural and morphological study of the nanocomposite film was analyzed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transforms infrared (FTIR), Raman spectroscopy, photoluminescence, and dynamic light scattering. The XRD graph and Raman spectra indicate the synthesized nanocrystalline anatase form of TiO2 nanoparticles. The characteristic peak of Ti-O-Ti bonds is observed between 600 and 850 cm−1 in the FTIR spectrum. Additionally, TIC film exhibited antibacterial properties against E. coli and Bacillus subtilis. The colorimetric method was utilized to determine the glucose concentration. The TIC film reveals that the minimum detectable concentration is 0.4 mM. This easy-to-develop TIC nanocomposite film shows good stability. Therefore, it can be a promising candidate for glucose-sensing applications.

Current advancements and prospects of enzymatic and non-enzymatic electrochemical glucose sensors

This review discusses the most current developments and future perspectives in enzymatic and non-enzymatic glucose sensors, which have notably evolved over the preceding quadrennial period. Furthermore, a thorough exploration encompassed the sensor's intricate fabrication processes, the diverse range of materials employed, the underlying principles of detection, and an in-depth assessment of the sensors' efficacy in detecting glucose levels within essential bodily fluids such as human blood serums, urine, saliva, and interstitial fluids. It is worth noting that the accurate quantification of glucose concentrations within human blood has been effectively achieved by utilizing classical enzymatic sensors harmoniously integrated with optical and electrochemical transduction mechanisms. Monitoring glucose levels in various mediums has attracted exceptional attention from industrial to academic researchers for diabetes management, food quality control, clinical medicine, and bioprocess inspection. There has been an enormous demand for the creation of novel glucose sensors over the past ten years. Research has primarily concentrated on succeeding biocompatible and enhanced sensing abilities related to the present technologies, offering innovative avenues for more effective glucose sensors. Recent developments in wearable optical and electrochemical sensors with low cost, high stability, point-of-care testing, and online tracking of glucose concentration levels in biological fluids can aid in managing and controlling diabetes globally. New nanomaterials and biomolecules that can be used in electrochemical sensor systems to identify glucose concentration levels are developed thanks to advances in nanoscience and nanotechnology. Both enzymatic and non-enzymatic glucose electrochemical sensors have garnered much interest recently and have made significant strides in detecting glucose levels. In this review, we summarise several categories of non-enzymatic glucose sensor materials, including composites, non-precious transition metals and their metal oxides, hydroxides, precious metals and their alloys, carbon-based materials, conducting polymers, metal-organic framework (MOF)-based electrocatalysts, and wearable device-based glucose sensors deeply.

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.

Electrodeposited Fabrication of CeO2 Branched-like Nanostructure Used for Nonenzymatic Glucose Biosensor

The fabrication of nonenzymatic glucose sensors is essential because of the enhancement in the selectivity and accuracy of these sensors. In this work, we used the electrodeposition approach to prepare a CeO2-based electrode for nonenzymatic glucose detection. A CeO2 branched-like nanostructure was successfully fabricated by electrodeposition on the surface of a Au substrate electrode at room temperature. The effects of cyclic voltammetry, CH3COOH content, and scan cycle number on the formation of the CeO2 branched-like nanostructure were investigated. The fabricated electrodes were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The results showed that a CeO2 branched-like nanostructure could be obtained with a CH3COOH content of 1.0 mL and a scan cycle number of 100 in a solution containing 0.015 M Ce(NO3)3, 0.01 M KCl, and 0.02 M CH3COONH4 and with a scan rate of 400 mV/s. The electrochemical characteristics of the sensor were examined by chronoamperometry and cyclic voltammetry. The results showed that the sensitivity of the sensor was 37.72 μA/mM·cm2 and the limit of detection (LOD) of the sensor was 0.093 mM. The findings in this work prove that it is feasible to fabricate CeO2-based sensors for nonenzymatic glucose detection.

(Invited) Non-Enzymatic Glucose Sensor Fabricated By Ni-Nanowires Decorated Graphene Gated FETs

In this study, an innovative non-invasive glucose sensor made of nickel nanowire-decorated graphene-gated field-effect transistors is demonstrated. Due to the redox reaction between nickel nanowires and glucose molecules in weakly alkaline solution, electron exchange occurs when Ni(III) reacts with glucose to form Ni(II) and gluconolactone. In order to improve the sensitivity of the glucose sensor and reduce the detection limit, we compared the characteristics of the glucose sensor fabricated by nickel nanowires on gold surface and graphene/gold surface, respectively. Since the CVD-grown graphene film has excellent electrical conductivity and no defects, the electrons generated by the redox reaction can be quickly and evenly dispersed and are not easily neutralized, resulting in a change on the gate potential, thereby affecting the current between the source and the drain metal, and then the glucose concentration in the solution can be deduced. It can be seen from the experiments that the glucose sensor with graphene film has better current stability, lower detection limit and better linear relationship between current and concentration. The demonstrated nickel wire-decorated graphene-gated FET biosensor can be used for the quantification of glucose with a linear range of 10-50 mM and a detection limit of 51nM. Figure 1

Exploiting synergistic interaction in Cu-Zn-Ni alloy oxide films prepared by one-step anodizing for a highly sensitive non-enzymatic glucose sensor

A highly sensitive and precise electrochemical biosensor for glucose detection was developed by coupling synergetic catalysis of Cu-Zn-Ni oxide films. To enhance the catalytic performance of alloy, potentials between −0.5 V and 1.5 V are selected for potentiostatic oxidation. Notably, the oxidation process reveals the influence of Cl− in the electrolyte, leading to electrode surface etching, with increasing etching and grain boundary collapse at higher potentials. The electrochemical performance of the electrode was comprehensively evaluated using cyclic voltammetry (CV) and amperometric response in alkaline conditions. The catalytic electrode has an impressive linear response in the concentration range of 0.1 ∼ 1.0 mM glucose, with a sensitivity of 3775.11 μA·mM−1. Furthermore, the electrode exhibits remarkable stability and anti-interference properties, rendering it suitable for non-enzymatic glucose sensing applications.

Cu-Ag bimetallic nanostructures with high glucose sensing performance fabricated by a scalable and reproducible method

A scalable and repeatable synthetization method is introduced to fabricate Cu-Ag bimetallic nanostructures as a stable, robust, fast-response and enzyme-free glucose sensor. Cu nanocolumns were constructed on the FTO substrate using the glancing angle deposition (GLAD). Then a thin layer of Ag is deposited on the Cu nanocolumns through a galvanic replacement reaction. The Cu-Ag nanostructures with different morphologies were developed by tuning the concentration and the reaction time of the galvanic replacement process. Various electrochemical characterizations, including cyclic voltammetry and electrochemical impedance spectroscopy (EIS), were performed to determine the superior electrocatalytic activity of the electrodes. The results reveal that the superior electrocatalytic performance toward glucose oxidation was achieved with Cu-Ag fabricated under the AgNO3 concentration of 5 mM and with a reaction time of 30 s. The sensor exhibits a fast response of ∼2 s with an excellent sensitivity of 3802 and 712 μAcm−2 mM−1 in two wide linear ranges of 0.01–3 mM and 3–8 mM and an optimum potential of 0.65 V. The proposed Cu-Ag sensor showed considerable enhancement of electrocatalytic activity compared to Cu or Ag monometallic structures due to the synergistic effect. In addition, the current bimetallic sensor regarding its outstanding precision and its reproducibility provides a promising method for large scale fabrication of non-enzymatic glucose sensors.

Trimetallic ZIF-Derived Ni–Cu/NC Rhombic Dodecahedron Nanostructures on Butter Sheet Paper as a Flexible Electrochemical Probe for Nonenzymatic Glucose Sensors

Trimetallic ZIF-Derived Ni–Cu/NC Rhombic Dodecahedron Nanostructures on Butter Sheet Paper as a Flexible Electrochemical Probe for Nonenzymatic Glucose Sensors

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

Single step hydrothermal synthesis of CuS/MnS composite for electrochemical non-enzymatic glucose sensor

In this work, a single step hydrothermal technique was used to synthesize CuS/MnS electrode material as efficient electrocatalyst for electrochemical non-enzymatic glucose sensor. The nanocomposites were characterized by FE-SEM, TEM, XRD, and XPS. Glassy carbon electrodes loaded with CuS/MnS composite was used for the investigation of electrochemical properties. The results showed a sensitivity and detection limit of 371.66 μA mM−1 cm−2 and 1.87 μM, respectively. The selectivity of the sensor for potentially interfering species was also studied. The CuS/MnS composite-based nonenzymatic glucose sensor exhibited considerable stability, selectivity for interfering species, and viability for glucose determination in diluted human serum samples.

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

Pyridine-Regulated Lamellar Nickel-Based Metal-Organic Framework (Ni-MOF) for Nonenzymatic Electrochemical Glucose Sensor.

2D metal-organic frameworks (MOFs) are considered as promising electrochemical sensing materials and have attracted a lot of attention in recent years. Compared with bulk MOFs, the construction of 2D MOFs can increase the exposure of active sites by obtaining a larger surface area ratio. Herein, a facile one-pot hydrothermal synthesis of pyridine-regulated lamellar Ni-MOFs with ultrathin and well-defined 2D morphology is described. Compared with the bulk structure, the 2D lamellar Ni-MOF has higher surface area and active site density, showing better electrochemical glucose sensing performance. The 2D lamellar Ni-MOF exhibits a fast amperometric response of less than 3 s and a high sensitivity of 907.54µA mm-1 cm-2 toward glucose with a wide linear range of 0.5-2665.5 µm. Furthermore, the 2D lamellar Ni-MOF also possesses excellent stability and reproducibility, and can be used to detect glucose with high accuracy and reliability in different environments.

Cu microspheres decorated ZnO@CNT/Carbon cloth flexible biosensor for simultaneous determination of glucose and uric acid

It is extremely important to simultaneously detection different biomarkers in various biological systems. Hereby, we have developed an original flexible nonenzymatic glucose and uric acid sensor using carbon cloth loaded with copper microspheres (Cu MSs) and ZnO nanoparticles decorated single-walled carbon nanotubes (Cu MSs/ZnO@CNTs/CC). Firstly, ZnO@CNTs was synthesized via sol–gel method, and then Cu MSs were uniformly electrodeposited on ZnO@CNTs/CC substrate rapidly. Morphological and compositional characteristics were examined to confirm the successful decoration of Cu microspheres and ZnO nanoparticles. Importantly, the nanocomposite electrode displayed remarkable electrocatalytic activity for glucose and UA, including wide linear detection range, low detection limit, outstanding sensitivity, respectively. Moreover, the nanostructure biosensor exhibited fast response time (0.1 s) and favorable long-term stability, which are attributed to synergistic catalytic effects: (a) the large specific surface area of CNTs offered abundant sites for thedecoration of ZnO nanoparticles, and (b) the rough nanosheets assembled Cu microspheres could expose plentiful active sites. Finally, in practical serum samples, the sensor also exhibits considerably favorable precision and accuracy. As such, the novel flexible Cu MSs/ZnO@CNTs/CC sensor developed with economical and efficient preparation method provided a new easy and sensitive platform for glucose and UA determination in real application.

Copper Selenide Micro/Nanocrystals on Carbon Paper via Chemical Vapor Deposition Selenylation as Electrodes for Non-enzymatic Glucose Sensing

Copper Selenide Micro/Nanocrystals on Carbon Paper via Chemical Vapor Deposition Selenylation as Electrodes for Non-enzymatic Glucose Sensing

A review on nanosensors to detect diabetes

Diabetes mellitus, a serious disease affecting millions of people worldwide, is a disease characterized by increased levels of glucose concentration in the blood. Monitoring blood glucose has been declared a crucial and important tool that makes diabetes management probable. A large number of suitable glucose biosensors have been developed so far. This research has particularly focused on covering achieving biocompatible and improved sensing platforms which are evolving with the contribution of novel materials. The motivation for writing this review is to discuss and review the recent advances in enzymatic and non-enzymatic glucose sensors evolved in the last few years.

Negative current response of non–enzymatic glucose sensor based on pure PEDOT: PSS conductive polymer

A simple non - enzymatic glucose sensor was successfully fabricated from a conductive polymer namely PEDOT: PSS with a facile drop coating on a screen-printed carbon electrode (SPCE). The amperometric technique was used in monitoring the current response of the glucose sensor in the NaOH and PBS solutions. A notable and distinct observation emerged, wherein the negative current response was observed as the glucose concentration was increased. The negative current response can be attributed to a unique mechanism of the glucose sensor namely the selective adsorption of glucose molecules. The current responses with various glucose concentrations in the NaOH and PBS solutions were identified as power laws with the equations of I (µA) = 56.519 C−0.331 (mM) and I (µA) = 50.724 C−0.029, respectively. The sensitivity values are 672 mM−1 cm−2 and 21 mM−1 cm−2 in NaOH and PBS, respectively. The limit of detection (LOD) was determined to be 0.5 mM for NaOH and 0.01 mM for PBS; the glucose sensor demonstrated superior sensitivity in NaOH because of the electrolyte strength. The numerous advantages of the present non-enzymatic glucose sensor modified with PEDOT: PSS on SPCE are the ease of fabrication, low cost, rapid monitoring, precise measurement, high sensitivity and selectivity, good reproducibility, and with long-term stability. The fabricated glucose sensor is suitable as a portable sensor for diabetes patients without utilizing elaborate and expensive laboratory protocols.

Performance comparison of non-enzymatic electrochemical glucose sensor with bimetallic NiMo–MOF and CoMo–MOF

Performance comparison of non-enzymatic electrochemical glucose sensor with bimetallic NiMo–MOF and CoMo–MOF

Cu2O/MXene/rGO Ternary Nanocomposites as Sensing Electrodes for Nonenzymatic Glucose Sensors

Cu₂O/MXene/rGO Ternary Nanocomposites as Sensing Electrodes for Nonenzymatic Glucose Sensors