Non-enzymatic Electrochemical Glucose Sensor Research Articles

Printing surface cuprous oxides featured liquid metal for non-enzymatic electrochemical glucose sensor

Electrochemical glucose sensors that rely on two-dimensional (2D) oxides have attracted significant attention owing to the strong sensing activity of 2D oxides, but their practical application is hindered by the complexity and high cost of fabrication of electrodes and integrated devices. Herein, a convenient and effective fabrication route that includes printing a Ga-based liquid metal (LM) as a current collection electrode, followed by growing electrochemically active 2D oxides directly on the surface of Ga-based LMs under mild conditions, is developed for non-enzyme-based electrochemical sensors. Specifically, 2D annealed Cu-Oxide (ACO) is successfully grown on a printed Ga electrode through a galvanic replacement reaction, resulting in the formation of a mechanically and electrically well-matched interface between the active sensing materials and the current collection substrate. Benefitting from the high quantity of 2D ACO and good charge transfer at the interface, the as-prepared ACO electrode exhibits attractive glucose sensing performance, with a wide linear range (1 μM-10 mM) of effective detection, low detection limit down to 1 μM, and high sensitivity of 0.87 μA·mM-1·cm-2. Our study highlights the potential of using LMs in bio-sensing applications and provides a non-enzyme-based electrochemical biosensor platform for effective glucose detection in diets and clinical diagnostic settings.

Green synthesized gold nanoparticles and CuO-based nonenzymatic sensor for saliva glucose monitoring.

Glucose, essential for brain and muscle functions, requires careful monitoring in diabetes and other chronic disease management. While blood glucose monitoring provides precise information about these diseases, it remains an invasive method. Saliva glucose monitoring could offer an alternative approach, but the glucose concentration in saliva is very low. In this work, we report a simple, low-cost, highly sensitive nonenzymatic electrochemical glucose sensor. We developed this sensor using green synthesized gold nanoparticles (AuNPs) and wet chemical synthesized copper oxide (CuO) nanoparticles on a screen-printed carbon electrode (Au/CuO/SPCE). The sensor's high sensitivity results from dual amplification strategies using AuNPs and CuO nanomaterials, each demonstrating catalytic activity towards glucose. This shows promising potential for saliva glucose monitoring. The AuNPs were synthesized using an Au precursor and orange peel extract (OPE), yielding stable colloidal AuNPs with a mean diameter of about 37 nm, thus eliminating the need for additional capping agents. Under optimal conditions, amperometric tests revealed that the sensor responded linearly to glucose concentrations ranging from 2 μM to 397 μM with a sensitivity of 236.70 μA mM-1 cm-2. Furthermore, the sensor demonstrated excellent reproducibility, stability and high selectivity for glucose in the presence of different biomolecules. We validated the sensor's efficacy by measuring glucose in human saliva, showing its potential for noninvasive glucose monitoring. This research advances the development of point-of-care devices, positioning the sensor as a promising tool for noninvasive glucose monitoring and improved diabetes management.

One-Step Method for the Direct Growth of NiO Nanoflowers on Pencil Graphite Electrode for Highly Sensitive Non-Enzymatic Glucose Sensing

Electrochemical glucose sensors, including enzymatic and non-enzymatic sensors, have been considered as quick, accurate, and efficent means for glucose measurement. Recently, non-enzymatic electrochemical glucose sensor based on metal oxides have been paid attention to develop thank to their outstanding behaviours. In most of these studies, metal oxides were synthesized individually and subsequently deposited on the electrode surface using a binder. In this study, we aim at developing a non-enzymatic glucose sensor based on NiO nanoflowers directly grown on a commercial pencil graphite electrode. NiO matetials were deposited on the electrode without a binder via a facile and low-cost chemical procedure. The synthesised materials’ morphologies and components of were characterized by a field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction analyses. Electrocatalytic performance was recorded by cyclic voltammetry and chronoamperometry. The resulting NiO nanoflowers, characterized by funnel-shaped structures measuring 500–600 nm in diameter and 20 nm in thickness, were formed on the pencil graphite electrode. The fabricated electrode showed a remarkably high sensitivity of 337 μA mM−1 cm−2, a low limit of detection of 4 μM, and good selectivity. The fabricated electrode can be a potential candidate for clinically medical applications.

Green synthesis of reduced graphene oxide (rGO) and its applications in non-enzymatic electrochemical glucose sensors

The synthesis of reduced graphene oxide (rGO) is a challenging task for industrial applications due to the absence of a simple and cost-effective synthesis method. This study proposes an environmentally friendly approach to synthesizing rGO using cow urine as a reducing agent, which eliminates the use of hazardous chemicals. The efficacy of this method was confirmed through various analyses, including UV Vis, Fourier transform infrared, and X-ray diffraction, which demonstrated the successful removal of oxygen-containing functions in GO via reduction with cow urine. The synthesized rGO-10 was utilized to fabricate electrochemical nonenzymatic glucose sensors, which exhibited a rapid response time and excellent amperometry response. The sensors used in this study demonstrated a sensitivity of 19.17 μAcm−2mM−1 when optimized for a glucose concentration of 2 mM in human serum. The sensors demonstrated a wide response range, covering a range of 0.2 to 10 mM, and a low detection limit of 1.9019 µM. Additionally, the sensors displayed desirable attributes about repeatability, reproducibility, and stability.

One-step hydrothermal synthesis of CuS/MoS2 composite for use as an electrochemical non-enzymatic glucose sensor

Early diagnosis may be crucial for the prevention of chronic diabetes mellitus. For that herein, we prepared a CuS/MoS2 composite for a non-enzymatic glucose sensor through a one-step hydrothermal method owing to the synergetic effect of CuS/MoS2. The surface morphology of CuS/MoS2 was studied by Field Emission Scanning Electron Microscopy (FESEM) and Cs-corrected Scanning Transmission Electron Microscopy (Cs-STEM). The crystallinity and surface composition of CuS/MoS2 were analyzed by X-ray Diffraction (XRD) and X-ray Photoelectron Spectroscopy (XPS) respectively. The working electrode was prepared from CuS/MoS2 electrocatalyst, and for that dispersed solution of electrocatalyst was used to fabricate the material-loaded glassy carbon electrode (GC). CuS/MoS2 composite shows the viability of electrocatalyst to oxidize glucose in an alkaline solution with sensitivity and detection limit of 252.71 μA mM−1 cm−2 and 1.52 μM respectively. The proposed glucose sensor showed reasonable stability and potential selectivity during electrochemical analysis. Accordingly, the CuS/MoS2 composite has potential as a viable material for glucose sensing in diluted human serum.

Non-enzymatic glucose electrochemical sensor based on nitrogen-doped graphene modified with polyaniline and Fe3O4@MIL-101-NH2 nano framework

In this study, a novel highly sensitive and selective non-enzymatic glucose sensor was fabricated by coating simple and cheap graphite sheet (GS) electrodes with a proper conductive nanocomposite containing nitrogen-doped functionalized graphene (NFG), conductive polyaniline (PANI), and core–shell nanoparticles (Fe3O4@MIL-101-NH2). The results revealed that the core centers of iron oxide nanoparticles shelled by MIL-101-NH2 enhanced the electron transfer and led to more conductivity, also their existence caused the limitation of the MOF’s low conductivity. In addition, using Fe3O4@MIL-101-NH2 in the nanocomposite structure led to more sensitivity and selectivity at glucose monitoring due to its amine groups and unique structure. The results showed that NFG/PANI/Fe3O4@MIL-101-NH2 nanocomposite provided a large surface area besides enhanced electron transfer and catalytic properties that lead to proper oxidation of glucose with two linear ranges of 0.5 – 10 µM and 100 µM – 25 mM and a low detection limit of 0.3 µM (S/N = 3). Furthermore, the relative standard deviation (RSD%) in all detection processes was lower than 9 %. Finally, the performance of fabricated non-enzymatic sensor (GS/NFG/PANI/Fe3O4@MIL-101-NH2) in human fluids real samples including serum and plasma was acceptable which significantly indicates that it is toward monitoring of glucose in clinical applications.

Electrochemical nonenzymatic glucose sensors catalyzed by Au nanoclusters on metallic nanotube arrays and polypyrrole nanowires

Monitoring blood glucose level is critical, since its abnormality leads to diabetes and causes death, even though glucose is essential for human living. Herein, the sensing study was performed on electrochemical nonenzymatic glucose sensors, which are composed of an Au nanocluster (AuNC) catalyst deposited on a metallic nanotube array (MeNTA) and polypyrrole nanowire (PPyNW). The AuNC was produced by irradiating a femtosecond pulse laser to the Au precursor solution, and it is a simple and facile method. The successful deposition of AuNC on both MeNTA and PPyNW was confirmed by means of the surface morphology and the Au content increase. On the exploration by cyclic voltammetry in alkaline condition, AuNC/MeNTA electrodes showed better performance than AuNC/PPyNW electrodes: The former was a remarkable electrocatalytic detector towards glucose oxidation with better sensitivity, lower detection limit, wider linear range, and longer-term stability without interference from potential interfering agents such as ascorbic acid, urea, NaCl, KCl, etc. Moreover, nonenzymatic AuNC/MeNTA electrodes exhibited high precision and accuracy in real human blood samples and, thus, can be a promising candidate in glucose sensing applications.

A Highly Sensitive Non-Enzymatic Glucose Electrochemical Sensor Electrode Material of CuO Nanospheres/Activated Carbon Composites

A Highly Sensitive Non-Enzymatic Glucose Electrochemical Sensor Electrode Material of CuO Nanospheres/Activated Carbon Composites

Recent advances in electrochemical non-enzymatic glucose sensor for the detection of glucose in tears and saliva: A Review

Recent advances in electrochemical non-enzymatic glucose sensor for the detection of glucose in tears and saliva: A Review

Copper nanoparticles/polyaniline/molybdenum disulfide composite as a nonenzymatic electrochemical glucose sensor

A Cu@Pani/MoS2 nanocomposite was successfully synthesized via combined in-situ oxidative polymerization and hydrothermal reaction and applied to an electrochemical nonenzymatic glucose sensor. The morphology of the prepared Cu@Pani/MoS2 nanocomposite was characterized using FE-SEM and Cs-STEM, and electrochemical analysis was performed using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and chronoamperometry techniques. Electrostatic interaction between Cu@Pani and MoS2 greatly enhanced the charge dispersion, electrical conductivity, and stability, resulting in excellent electrochemical performance. The Cu@Pani/MoS2 was used as an electrocatalyst to detect glucose in an alkaline medium. The proposed glucose sensor exhibited a sensitivity, detection limit, and wide linear range of 69.82 μAmM−1cm−2, 1.78 μM, and 0.1–11 mM, respectively. The stability and selectivity of the Cu@Pani/MoS2 composite for glucose compared to that of the potential interfering species, as well as its ability to determine the glucose concentration in diluted human serum samples at a high recovery percentage, demonstrated its viability as a nonenzymatic glucose sensor.

NiCo2O4/Ti2NbC2 (double MXene) nanohybrid-based non-enzymatic electrochemical biosensor for the detection of glucose in sweat.

The non-enzymatic electrochemical sensors are attractive due to their high sensitivity, quick detection, low cost, and simple construction. Hence, in this work, a non-enzymatic biosensor was constructed with NiCo2O4 nanoparticles (~ 82nm) decorated over Ti2NbC2 nanosheets by an in-situ method. The crystal structure, phase purity, morphology and elemental composition of the synthesized NiCo2O4/Ti2NbC2 nanohybrid was investigated using XRD, Raman and FESEM analysis. The electrocatalytic and electrochemical behaviour of the prepared nanohybrid was investigated using cyclic voltammetry and amperometry analysis. Hybrid of NiCo2O4/Ti2NbC2 produces a biocompatible, electrochemically active surface with enhanced electrical conductivity. The enhanced surface area of NiCo2O4 and superior electrical conductivity of Ti2NbC2 nanosheets helped to develop non-enzymatic electrochemical glucose sensor with enhanced sensitivity (425.6 µA mM-1cm-2), low limit of detection and quick response time that satisfy glucose detection applications. Thus, the developed non-enzymatic electrochemical glucose sensor has excellent electrochemical properties and making it as a strong candidate for the detection of glucose concentration in sweat.

One-pot hydrothermal synthesis of CuS/CoS composite for electrochemical non-enzymatic glucose sensor

Herein, a CuS/CoS electrode material was synthesized using a one-step hydrothermal method as an efficient electrocatalyst for a non-enzymatic glucose sensor. The nanocomposites were characterized by Field emission scanning electron microscope (FE-SEM), Transmission electron microscope (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The CuS/CoS composite loaded glassy carbon electrode was used to investigate electrochemical properties using cyclic voltammetry (CV) and chronoamperometry (CA). The results showed 314.85 μA mM−1 cm−2 sensitivity and 1.71 μM detection limit. Selectivity of the sensor was examined over potential interfering species that exhibits the distinct increased current response on addition of glucose before and after addition of interfering species evident the selectivity of CuS/CoS electrode material. Moreover, the CuS/CoS composite-based non-enzymatic glucose sensor revealed considerable stability, selectivity over interfering species, and viability for glucose determination in diluted human serum samples, which provide efficient and cost-effective strategy to develop non-enzymatic electrochemical glucose sensing platform.

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.

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.

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.

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

Recent Advances in Metal-Organic Frameworks (MOFs) and Their Composites for Non-Enzymatic Electrochemical Glucose Sensors.

In recent years, with pressing needs such as diabetes management, the detection of glucose in various substrates has attracted unprecedented interest from researchers in academia and industry. As a relatively new glucose sensor, non-enzymatic target detection has the characteristics of high sensitivity, good stability and simple manufacturing process. However, it is urgent to explore novel materials with low cost, high stability and excellent performance to modify electrodes. Metal-organic frameworks (MOFs) and their composites have the advantages of large surface area, high porosity and high catalytic efficiency, which can be utilized as excellent materials for electrode modification of non-enzymatic electrochemical glucose sensors. However, MOFs and their composites still face various challenges and difficulties that limit their further commercialization. This review introduces the applications and the challenges of MOFs and their composites in non-enzymatic electrochemical glucose sensors. Finally, an outlook on the development of MOFs and their composites is also presented.

Copper decorated polyaniline nanowires: A tow-step electrochemical synthesis and a development of a non-enzymatic electrochemical glucose sensor

In this work, a nanostructured electrode material based on copper metal decorated polyaniline nanowires (PANi NWs@Cu) was directly fabricated on a Pt (Pt/PANi NWs@Cu) microelectrode using a novel and effective two-step electrochemical procedure. Herein, the polyaniline nanowires were firstly electropolymerized on the Pt microelectrode using a cyclic voltammetry method, and the copper metal coated onto the polyaniline nanowires were fabricated via a chronoamperometry deposition to form the PANi NWs@Cu with an average diameter of 85 nm. The electrocatalytic activity showed that the as-synthesized PANi NWs@Cu can directly oxidize glucose in alkaline medium, which suggested that the PANi NWs@Cu can be applied as an artificial enzyme for development of a non-enzymatic electrochemical glucose sensor. Obtained results exhibits that the Pt/PANi NWs@Cu has the ability to directly detect glucose with a rapid response, high selectivity, good repeatability, excellent stability with a wide linear range of glucose concentration from 0.5 mM to 50.0 mM and a low detection limit of 94 μM. The developed Pt/PANi NWs@Cu-based electrochemical sensor also shows the ability to directly detect glucose in a 5% glucose intravenous infusion sample with an error of 1.21% from a labelled value.

Carbon nanomaterials and their composites for electrochemical glucose biosensors: A review on fabrication and sensing properties

BackgroundWith the increasing prevalence of diabetes that increases the risk of cardiovascular diseases, kidney failure, nerve degeneration, eye damage, lower extremity amputations and birth defects, the demand for highly efficient glucose sensors has attracted significant attention worldwide. In this regard, carbon nanomaterials-based electrochemical glucose sensors have shown great potential in the detection and monitoring of glucose. MethodsDifferent forms of carbon such as carbon nanotubes, graphene, reduced graphene oxide, carbon nanofibers, activated and amorphous carbon, carbon spheres, carbon nanoparticles, carbon quantum dots, carbon nanorods, carbon nanocages etc. and their hybrids have been extensively researched for highly efficient glucose sensors due to their large surface area, porosity, lightweight, thermal stability, excellent mechanical properties, ease of fabrication, high electrical conductivity, excellent catalytic properties and fast electron transfer kinetics. Significant findingsDue to their large surface area and tunable porosity, carbon nanomaterials have been used as a scaffold for the immobilization of large quantities of bioreceptor units such as enzymes and highly catalytic metal or metal oxide nanostructures, which can enhance the electroanalytical properties of the biosensor. In this review paper, the fabrication and electroanalytical properties of carbon nanomaterials based enzymatic and nonenzymatic electrochemical glucose sensors have been reviewed and their sensing mechanisms are discussed.