Electrochemical Glucose Sensor Research Articles

Wearable electrochemical sensor based on bimetallic MOF coated CNT/PDMS film electrode via a dual-stamping method for real-time sweat glucose analysis

Non-invasive wearable sweat glucose sensors are expected to be highly desirable for personalized diabetes management. Therefore, developing facile, convenient, and scalable manufacturing method of such wearable sensors is urgently needed. Herein, we report a simple and low-cost stamping-vacuum filtration dry transfer (SVFDT) method for construction of a wearable sweat glucose electrochemical sensor. In this patch, a three-electrode array template was made by using a polyvinyl chloride (PVC) stamp, followed by the preparation of multiwalled carbon nanotubes (MWCNTs)/polydimethylsiloxane (PDMS) (MP) film electrode using the vacuum-filtration dry transfer method. In addition, for further enhancing the conductivity of the electrode, another similar stamp with a raised surface dipping carbon nanotubes (CNTs) conductive coating was stamped on the surface of the MP electrode to obtain CNTs/MWCNTs/PDMS (CMP) electrode. CMP electrode was modified with the enzyme-like Ni-Co metal-organic framework (MOF) material which showed good electro-catalytic activity and achieved high sensitivity for glucose detection with a low detection limit of 6.78 μM and a wide linear range of 20 μM - 1.1 mM. More importantly, the Ni-Co MOF modified CMP (NCMP) electrode also displayed high stability under stretching and bending conditions. Finally, the sweat absorbent cloth was combined with the NCMP film electrode to form a wearable flexible electrochemical sensor patch, which could adhere to the skin to enrich sweat and realize real-time detection of sweat glucose with high accuracy. This SVFDT method can also be applied to the fabrication of other electronic devices.

Construction of a portable enzyme-free electrochemical glucose detection system based on the synergistic interaction of Cu-MOF and PtNPs

Three enzyme-free electrochemical glucose (GLU) sensors with bimetallic structures were constructed by electrodeposition of gold and copper nanoparticles (AuNPs/CuNPs), nickel and copper nanoparticles (NiNPs/CuNPs), and a copper-based metal-organic framework (Cu-MOF) combined with PtNPs, respectively. Amongst, the Cu-MOF/PtNPs on a gold electrode (GE) exhibited the best catalytic performance for GLU oxidation due to the synergistic amplification. The relevant electrochemical behaviour of GLU showed that two OH- and two electrons were involved in the process. The differential pulse voltammetry (DPV) enables the establishment of linearity in the concentration of 0.40–25.00 mM, with a detection limit (LOD) of 0.06 mM and a sensitivity of 158.41 µA·mM−1cm−2. In addition, the Cu-MOF/PtNPs/GE sensor was used to detect GLU in oral liquid as well as human serum samples with a recovery rate of 97.00–103.98% and RSD less than 3.59%. Finally, a portable electrochemical detection system based on the STM32F103C8T6 microcontroller, obtained a GLU concentration 5.24 mM while detecting in a diluted injection where the value 5.40 mM was recorded by a commercial meter to show the system has very broad application prospects in the point-of-care setting.

L-Alanine Supported Autogenous Eruption Combustion Synthesis of Ni/NiO@RuO2 Heterostructure for Electrochemical Glucose and pH Sensor

Safety and quality control are important for long-term storage and preservation of food. Glucose and food pH are the two most common markers for evaluating food quality. Herein, we constructed a Ni/NiO@RuO2 heterostructure-based two-way sensor via a novel eruption combustion pattern (ECP) using non-conventional amino acid as a propellant. This approach has the unique points of interests of in situ doping of oxides and the formation of heterojunctions, providing well-developed pores and high surface areas to enhance the material performance. The Ni/NiO@RuO2 heterostructures have been tested as a bi-functional catalyst for glucose and pH sensing. The sensor exhibits a fast response time of <0.1 ± 0.02 s, a sensitivity of 641.95 ± 0.5 μA mM−1 cm−2 towards glucose with a 0.4 ± 0.08 μM detection limit and a linear response of 0.1 to 5 mM. As a pH sensor, it exhibits an acceptable sensitivity of −41.6 mV pH−1 with a response time of <50 s over a pH range of 2–12. Moreover, this bi-functional sensor based on Ni/NiO@RuO2 performs well when applied to a selection of beverage samples. This study provides a new scalable and low-cost approach to fabricating hetero-oxide nanostructures with controllable heterojunctions for various sensor applications.

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.

Cost-Effective and Fast Fabrication of Copper–Cobalt Electrochemical Glucose Sensor

Cost-Effective and Fast Fabrication of Copper–Cobalt Electrochemical Glucose Sensor

Highly sensitive glucose electrochemical sensor using sugar‐lectin interactions

AbstractIn this study, glucose oxidase (GOx) was immobilized on the electrode surface by layer‐by‐layer and gel membrane technique and characterized the GOx immobilized film morphology, H2O2 permeability, and glucose response. Concanavalin A (Con A)‐GOx multilayer electrodes showed higher glucose‐related current response than GOx‐bovine serum albumin gel membrane‐coated electrode, a common modification method. The thin thickness of the Con A/GOx multilayer film efficiently catalyzed the enzymatic reaction, and H2O2 was produced near the electrode surface, resulting in an immediate electrode response.

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.

Metal organic framework nanosheets in-situ derivatization of heterogeneous Cu2S/Ni3S2 nanoparticles for enhanced water splitting and glucose sensing

Metal organic frameworks (MOFs) are considered as promising electrocatalytic materials because of its good designability and structural diversity. Herein, the composite materials of Cu2S/Ni3S2@Ni-BDC/NF are successfully synthesized through the hydrothermal and electrodeposition methods. The distinctive heterostructure provides ample active sites and retains structural integrity to promote durability. When it is explored as bifunctional electrocatalyst, the overpotential of 63 mV at 10 mA cm−2 current density for the hydrogen evolution reaction (HER), the overpotential of 353 mV at 50 mA cm−2 current density for the oxygen evolution reaction (OER). In a two-electrode system, an extremely low cell voltage of 1.55 V is required to achieve 20 mA cm−2 current density. Moreover, Cu2S/Ni3S2@Ni-BDC exhibits satisfactory glucose sensitivity of 56,220 μA mM−1 cm−2 and outstanding anti-interference performance. This design not only successfully constructs 0D/2D heterogeneous interface of electrocatalyst, but also demonstrates the multifunctional application potential of water splitting and glucose electrochemical sensors.

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

Development of Rapid Dispense-Printed Flexible Interdigitated Electrode Modified with rGO-TiO2 Nanohybrid for Glucose Detection

A rapid and facile method in developing a printed electrochemical glucose sensor constructed using flexible interdigitated electrode (IDE) employed with reduced graphene oxide (rGO)-Titanium dioxide (TiO2) is demonstrated. A 2 × 3 silver (Ag)-based IDE array based on a simulated IDE model, was fabricated via a single-step dispense-printing within less than 5 min, while a rGO-TiO2 nanohybrid and glucose oxidase (GOx) enzyme was coated on the IDE surface simply via drop-casting method. Exceptional reproducibility and repeatability of the printed IDE functionalized with rGO-TiO2/GOx in terms of electrical and mechanical performance were observed. The stability of the sensor was investigated over a week period, in which 6%–7% performance degradation was recorded based on resistance measurement in flat state, whereas no further significant loss was noted over the same period in bending state. The IDE sensor was tested using chronoamperometry with varied glucose concentrations up to 30 mM, resulted in a stabilized current after 5 s. The sensitivity plot attained depicted a best linear fit of 0.988 obtained at response time of 60 s, whilst covering lowest detection at 0.05 mM and selective detection from ascorbic acid and uric acid. The application of this sensor could contribute as an alternative method to develop a reliable and economical glucose sensing wearable for independent monitoring.

Screen-Printed Textile-Based Electrochemical Biosensor for Noninvasive Monitoring of Glucose in Sweat.

Wearable sweat biosensors for noninvasive monitoring of health parameters have attracted significant attention. Having these biosensors embedded in textile substrates can provide a convenient experience due to their soft and flexible nature that conforms to the skin, creating good contact for long-term use. These biosensors can be easily integrated with everyday clothing by using textile fabrication processes to enhance affordable and scalable manufacturing. Herein, a flexible electrochemical glucose sensor that can be screen-printed onto a textile substrate has been demonstrated. The screen-printed textile-based glucose biosensor achieved a linear response in the range of 20-1000 µM of glucose concentration and high sensitivity (18.41 µA mM-1 cm-2, R2 = 0.996). In addition, the biosensors show high selectivity toward glucose among other interfering analytes and excellent stability over 30 days of storage. The developed textile-based biosensor can serve as a platform for monitoring bio analytes in sweat, and it is expected to impact the next generation of wearable devices.

Gold Nanoclusters with Two Sets of Embedded Enzyme Nanoparticles for Applications as Electrochemical Sensors for Glucose

Enzyme-based electrochemical biosensors have been widely used because of their sensitivity, rapidity, and highly target-specific reactions. However, the immobilized enzymes can hinder electron transfer on the surface of the electrode and can decrease the sensitivity of electrochemical biosensors. To overcome this problem, we synthesized conductive gold nanoclusters with two sets of embedded enzyme nanoparticles, which are called gold nanocluster-embedded dual-enzyme nanoparticles (AuNC-DENPs) composed of a glucose oxidase-stabilized gold nanocluster (GOX-AuNC) and a horseradish peroxide-stabilized gold nanocluster (HRP-AuNC). Moreover, the application of these nanoparticles as an enzyme-based highly sensitive electrochemical sensor was investigated. Owing to the effect of AuNCs, these nanoparticles have good conductivity compared to bare protein nanoparticles. In addition, the synthesized AuNC-DENPs enabled the combination of a two-enzyme cascade reaction, in which the GOX-AuNC component of the nanoparticle oxidized glucose to generate hydrogen peroxide, which then reacted with the adjacent HRP-AuNC component on the nanoparticle. Given the proximity of the two enzyme components in a single nanoparticle, the AuNC-DENPs markedly reduced the diffusion and decomposition of H2O2 during the cascade reaction and showed an enhanced catalytic reaction compared to a mixture of enzymes. As a result, the biosensor exhibited high sensitivity (18,944 μA/mM cm2) and could detect very low concentrations of glucose ranging from 5 to 320 nM and a LOD of 2.58 nM. In addition, by analyzing nontarget materials and serum together with glucose, it was confirmed that the sensor has good selectivity for glucose.

Fabric-Based Electrochemical Glucose Sensor with Integrated Millifluidic Path from a Hydrophobic Batik Wax

In recent years, measuring and monitoring analyte concentrations continuously, frequently, and periodically has been a vital necessity for certain individuals. We developed a cotton-based millifluidic fabric-based electrochemical device (mFED) to monitor glucose continuously and evaluate the effects of mechanical deformation on the device’s electrochemical performance. The mFED was fabricated using stencil printing (thick film method) for patterning the electrodes and wax-patterning to make the reaction zone. The analytical performance of the device was carried out using the chronoamperometry method at a detection potential of −0.2 V. The mFED has a linear working range of 0–20 mM of glucose, with LOD and LOQ of 0.98 mM and 3.26 mM. The 3D mFED shows the potential to be integrated as a wearable sensor that can continuously measure glucose under mechanical deformation.

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.

Wearable Electrochemical Glucose Sensors in Diabetes Management: A Comprehensive Review.

With the rising diabetic population, the demand for glucose sensing devices has also been on an increasing trend. Accordingly, the field of glucose biosensors for diabetes management has witnessed tremendous scientific and technological advancements since the introduction of the first enzymatic glucose biosensor in the 1960s. Among these, electrochemical biosensors hold considerable potential for tracking dynamic glucose profiles in real time. The recent evolution of wearable devices has opened opportunities to use alternative body fluids in a pain-free, noninvasive or minimally invasive manner. This review aims to present a comprehensive report about the status and promise of wearable electrochemical sensors for on-body glucose monitoring. We start by highlighting the importance of diabetes management and how sensors can contribute toward its effective monitoring. We then discuss the electrochemical glucose sensing mechanisms, evolution of such glucose sensors over time, different versions of wearable glucose biosensors targeting various biofluids, and multiplexed wearable sensors toward optimal diabetes management. Finally, we focus on the commercial aspects of wearable glucose biosensors, starting with existing continuous glucose monitors, followed by other emerging sensing technologies, and concluding with highlighting the key prospects toward personalized diabetes management in connection to an autonomous closed-loop artificial pancreas.

Analysing the bifunctional ability of CuO/BiOBr/rGO as an electrode for non-enzymatic glucose sensor and supercapacitor

Diabetes is a serious medical disease that involves regular blood glucose monitoring. There is a huge demand for cost-effective glucose sensors that can rapidly and accurately measure blood glucose levels. To meet this demand, nonenzymatic electrochemical glucose sensors have been developed for clinical research and are of significant interest. A CuO/rGO/BiOBr (CRB) composite was synthesized via a facile hydrothermal method. Electrochemical studies were conducted on the as-prepared composite to evaluate its suitability for sensing and energy storage applications. In this study, the sensing ability of the composites was examined at various molar concentrations of glucose. Thus, the synthesized composite exhibited a high sensitivity and excellent selectivity for glucose sensing. In addition, the CV, GCD and EIS findings indicate that the electrode is a suitable candidate for supercapacitor application. The synergetic effect of the materials makes the composite well-suited for dual applications.

Enzymeless Electrochemical Glucose Sensors Based on Metal–Organic Framework Materials: Current Developments and Progresses

Electrochemical glucose sensors play a crucial role in medicine, bioscience, food science, and agricultural science. Metal–organic frameworks possess exceptional properties, such as large specific surface area, high porosity, tunable pore structure, high catalytic activity, open metal active sites, and structural diversity. The catalytic activity of metal–organic frameworks enables electrocatalytic oxidation of glucose without the need for enzymes. Consequently, enzymeless electrochemical glucose sensors based on metal–organic framework materials have gained much attention and have been extensively studied for glucose detection. This mini-review provides an overview of the development and progress of enzymeless electrochemical glucose detection based on metal–organic framework material–modified electrodes, including doping materials, sensitivity, detection limit, and fast response capability. With the advancement of this technology, enzymeless electrochemical glucose sensors can continuously and stably detect glucose and can be utilized in various fields, such as wearable devices.

Flexible MWCNT/Silk fibroin film decorated with Pt NPs for electrochemical glucose sensors

Flexible glucose sensor has become a research focus of continuous blood glucose detection methods because it can easily and quickly detect the glucose content in human body fluids. We prepare a multi-walled carbon nanotube (MWCNT)/Silk Fibroin (SF) flexible film, decorated with platinum nanoparticles (Pt NPs) and loaded with glucose oxidase (GOx) to construct a Pt-MWCNT/SF glucose sensor. A flexible conductive film with an electrical conductivity of 8.5 × 10−5 S/m is prepared by controlling the content of MWCNT. The maximum breaking strength and elongation at the break of MWCNT/SF film are 19.12 MPa and 192%. The Pt-MWCNT/SF glucose sensor has excellent conductivity stability under mechanical deformation and accurately detects glucose in the presence of other biomolecules. The linear range of glucose response is 0.1 to 3.75 mM, and the sensitivity is 8.09 μA/mM·cm2. The biological electrode constructed based on MWCNT/SF film has excellent flexibility, which is expected to be integrated with other electronic devices for monitoring and managing human health.