Electrochemical Detection Of Glucose Research Articles

Electrochemically Deposited Cu(II)/Cu(I) Oxide Heterostructure as Highly Sensitive Platform for Electrochemical Detection of Glucose and Methanol

Electrochemically Deposited Cu(II)/Cu(I) Oxide Heterostructure as Highly Sensitive Platform for Electrochemical Detection of Glucose and Methanol

Low-interference and sensitive electrochemical detection of glucose and lactate using boron-doped diamond electrode and electron mediator menadione.

To minimize background interference in electrochemical enzymatic biosensors employing electron mediators, it is essential for the electrochemical oxidation of electroactive interfering species (ISs), such as ascorbic acid (AA), to proceed slowly, and for the redox reactions between electron mediators and ISs to occur at a low rate. In this study, we introduce a novel combination of a working electrode and an electron mediator that effectively mitigates interference effects. Compared to commonly used electrodes such as Au, glassy carbon, and indium tin oxide (ITO), boron-doped diamond (BDD) electrodes demonstrate significantly lower anodic current (i.e., lower background levels) in the presence of AA. Additionally, menadione (MD) exhibits notably slower reactivity with AA compared to other electron mediators such as Ru(NH3)63+, 4-amino-1-naphthol, and 1,4-naphthoquinone, primarily due to the lower formal potential of MD compared to AA. This synergistic combination of BDD electrode and MD is effectively applied in three biosensors: (i) glucose detection using electrochemical-enzymatic (EN) redox cycling, (ii) glucose detection using electrochemical-enzymatic-enzymatic (ENN) redox cycling, and (iii) lactate detection using ENN redox cycling. Our developed approach significantly outperforms the combination of ITO electrode and MD in minimizing IS interference. Glucose in artificial serum can be detected with detection limits of ~ 20μM and ~ 3μM in EN and ENN redox cycling, respectively. Furthermore, lactate in human serum can be detected with a detection limit of ~ 30μM. This study demonstrates sensitive glucose and lactate detection with minimal interference, eliminating the need for (bio)chemical agents to remove interfering species.

Carbon-supported nickel/nickel oxide nanohybrid composite as a high-performance sensor for electrochemical non-enzymatic glucose detection

Electrocatalytic oxidation of glucose on carbon-supported nickel/nickel oxide nanocomposite modified GCE.

Copper-based bimetallic metal–organic framework in-situ embedded of heterogeneous Cu nanoparticles for enhanced nonenzymatic glucose sensing

Copper-based metal–organic frameworks (MOFs) are recently emerging as encouraging electrocatalysts with high performance and stability for electrochemical detection of glucose. Herein, a simple one-step solvothermal in-situ derivative strategy is proposed to fabricate the novel heterogeneous electrocatalyst of Cu nanoparticles embedded bimetallic Cu@MCu-BDC-NH2 (M = Ni, Co and Zn) MOFs, which can enhance the conductivity via tailor the electronic structure and heterojunction interface. The optimal bimetallic Cu@CoCu-BDC-NH2 heterostructure exposes more active sites, the electronic interaction between metal-O enhanced the reactivity and electrical conductivity, and prominently boost the kinetics of glucose detection. The optimized Cu@CoCu-BDC-NH2 heterojunction structure as modified electrode nanomaterials exhibit the low detection limit (0.27 μM), wide linear range (0.5 μM–2 mM) and the high sensitivity (21157 μA mM−1 cm−2), which are successfully used in human serum and hold great stability and anti-interference. The density functional theory (DFT) calculation demonstrates that the adsorption energies of Cu@CoCu-BDC-NH2 heterostructure for glucose are −0.3 eV, suggesting good adsorption capacity for glucose. This work not only successfully establish Cu nanoparticles heterostructure interface with bimetallic MOFs for high-performance glucose sensors, but also emphasizes the importance of regulate the electronic microstructure of bimetallic MOFs for enhanced reaction kinetics.

Development of Redox-Active Lyotropic Lipid Cubic Phases for Biosensing Platforms.

Enzyme-based electrochemical biosensors play an important role in point-of-care diagnostics for personalized medicine. For such devices, lipid cubic phases (LCP) represent an attractive method to immobilize enzymes onto conductive surfaces with no need for chemical linking. However, research has been held back by the lack of effective strategies to stably co-immobilize enzymes with a redox shuttle that enhances the electrical connection between the enzyme redox center and the electrode. In this study, we show that a monoolein (MO) LCP system doped with an amphiphilic redox mediator (ferrocenylmethyl)dodecyldimethylammonium bromide (Fc12) can be used for enzyme immobilization to generate an effective biosensing platform. Small-angle X-ray scattering (SAXS) showed that MO LCP can incorporate Fc12 while maintaining the Pn3m symmetry morphology. Cyclic voltammograms of Fc12/MO showed quasi-reversible behavior, which implied that Fc12 was able to freely diffuse in the lipid membrane of LCP with a diffusion coefficient of 1.9 ± 0.2 × 10-8 cm2 s-1 at room temperature. Glucose oxidase (GOx) was then chosen as a model enzyme and incorporated into 0.2%Fc12/MO to evaluate the activity of the platform. GOx hosted in 0.2%Fc12/MO followed Michaelis-Menten kinetics toward glucose with a KM and Imax of 8.9 ± 0.5 mM and 1.4 ± 0.2 μA, respectively, and a linearity range of 2-17 mM glucose. Our results therefore demonstrate that GOx immobilized onto 0.2% Fc12/MO is a suitable platform for the electrochemical detection of glucose.

Rapid and facile preparation of NiFe-layered double hydroxide nanosheets as self-supported electrode for glucose detection in drink sample

Layered double hydroxides have been widely used for electrochemical glucose detection due to their layered structure with more active sites, but they suffer from lower electrical conductivity and long-time hydrothermal preparation. In this paper, NiFe-layered double hydroxide nanosheets supported on nickel foam (NiFe-LDH NSs/NF) was prepared using an ultrafast and facile method via in-situ corroding foam nickel in FeCl3 solution under room temperature, and the whole synthetic process can be accomplished within several minutes. The as-fabricated NiFe-LDH NSs/NF shows significant catalytic activity in the glucose oxidation, showing its great promise in glucose detection. As a self-supported electrode, NiFe-LDH NSs/NF is favorable for glucose detection, with a sensitivity of 9.79 and 3.29 mA mM−1 cm−2 within the linear range of 0.001 to 1.16 mM and 1.16 to 4.67 mM, respectively. Moreover, NiFe-LDH NSs/NF is also selective and reliable towards glucose detection in drink sample.

A Multifunctional Biosensor via MXene Assisted by Conductive Metal–Organic Framework for Healthcare Monitoring

AbstractFor real‐time care of metabolic diseases, it is highly demanded to simultaneously monitor metabolite content and diagnose muscle strength in a rapid and convenient way. However, such a biosensor with integrated functions of detecting chemical and biopotential signals at the same time has seldom been reported. In this work, a multifunctional biosensor, integrating the electrochemical detection of uric acid (UA) and glucose (Glu) in sweat, electrophysiological signal acquisition, and electrostimulation therapy, is designed. Hence, an electrophysiological MOF/MXene electrode is fabricated using highly conductive MXene and porous conductive metal–organic framework (c‐MOF, Ni3(HITP)2). Compared with commercial Ag/AgCl electrode, MOF/MXene electrode has lower electrode/skin interface impedance, higher stability and signal‐to‐noise (SNR). By utilizing the high charge storage capacity (CSC) of MOF/MXene electrode, it can realize muscle treatment by electrostimulation. Besides, with abundant active regions of c‐MOF, the electrode exhibits excellent electrochemical performance in detecting sweat metabolites. Multimodal signals detected by such integrated biosensors are wirelessly transmitted to a mobile terminal, showing significant potential on muscle theranostics and daily non‐invasive monitoring. Additionally, they offer timely nutritional guidance for individuals dealing with hyperuricemia or hyperglycemia.

Zwitterionic hydrogel for preserving stability and activity of oxidase enzyme for electrochemical biosensor

Enzymatic electrochemical biosensor is the most common analytical platform for medical diagnosis. To mimic the biological environment of the enzyme for maintaining the function of biosensor, zwitterionic hydrogels have been recognized as effective matrices for enzymatic immobilization. Herein, a zwitterionic hydrogel derived from a copolymer, poly[2-methacryloyloxyethyl phosphorylcholine (MPC)-co-N-methacryloyloxyethyl tyrosine methylester (MAT)] (PMM) was firstly applied as versatile coating to preserve stability and activity of oxidase enzymes, glucose oxidase (GOx) and lactate oxidase (LOx) for enzymatic electrochemical sensor. A screen-printed carbon electrode (SPCE) was sequentially coated with nitrogen-doped graphene (NDG), oxidase enzyme, and PMM mixed with Ru(II)bpy32+ and (NH4)2S2O8 followed by visible light irradiation for 3 min to induce PMM gelation. Electrochemical detection of glucose and lactate using the modified SPCE was performed via amperometry in the presence of hydrogen peroxide. The activity of both GOx and LOx immobilized on the modified SPCE was well maintained for 49 days at 87 and 80 %, respectively. Additionally, two different electrodes, a screen-printed graphene electrode (SPGE), and a screen-printed silver electrode (SPAgE), similarly modified gave the same satisfactory detection of spiked glucose and lactate in human plasma and sweat with 93–118 % recovery. This indicates the potential of the PMM hydrogel as a universal platform for preservation of enzymes which can be easily fabricated without the need for specific chemical modification of the electrode.

Nanoporous CuZn supported CuO nanoparticle electrodes for non-enzymatic electrochemical glucose detection

Nanoporous CuZn supported CuO nanoparticle electrodes for non-enzymatic electrochemical glucose detection

A Wearable Touch-Activated Device Integrated with Hollow Microneedles for Continuous Sampling and Sensing of Dermal Interstitial Fluid.

Dermal interstitial fluid (ISF) is emerging as a rich source of biomarkers that complements conventional biofluids such as blood and urine. However, the impact of ISF sampling in clinical applications has been limited owing to the challenges associated with extraction. The implementation of microneedle-based wearable devices that can extract dermal ISF in a pain-free and easy-to-use manner has attracted growing attention in recent years. Here, a fully integrated touch-activated wearable device based on a laser-drilled hollow microneedle (HMN) patch for continuous sampling and sensing of dermal ISF is introduced. The developed platform can produce and maintain the required vacuum pressure (as low as ≈ -53kPa) to collect adequate volumes of ISF (≈2µL needle-1 h-1 ) for medical applications. The vacuum system can be activated through a one-touch finger operation. A parametric study is performed to investigate the effect of microneedle array size, vacuum pressure, and extraction duration on collected ISF. The capability of the proposed platform for continuous health monitoring is further demonstrated by the electrochemical detection of glucose and pH levels of ISF in animal models. This HMN-based system provides an alternative tool to the existing invasive techniques for ISF collection and sensing for medical diagnosis and treatment.

Green synthesis of copper oxide nanoparticles using Amaranthus dubius leaf extract for sensor and photocatalytic applications

Copper oxide nanoparticles (CuO NPs) were produced through an environmentally friendly green synthesis. The characteristics of these green synthesized CuO NPs, including their structural, optical, morphological, and electrochemical properties, were examined using various characterization techniques. X-ray diffraction analysis revealed that the CuO NPs have a monoclinic structure with a C2/c space group. Electrochemical detection of glucose was carried out using cyclic voltammetry. The green synthesized CuO NPs exhibited excellent catalytic properties for both electrochemical sensing and photocatalysis. Significantly, these CuO NPs exhibited excellent selectivity and sensitivity in glucose detection, with a sensitivity of 370 μA mM−1 cm−2 and a detection limit of 1.0 μM. Furthermore, the CuO NPs demonstrated a substantial 84 % degradation of dyes within 150 min. These results underscore the potential of the green synthesized CuO NPs as a promising material for applications in both sensing and dye degradation.

Immobilizing glucose oxidase on AuCu hydrogels for enhanced electrochromic biosensing

Development of highly sensitive and accurate biosensors still faces a great challenge. Herein, glucose oxidase (GOx) is efficiently immobilized on the AuCu hydrogels owing to their porous structure and interfacial interaction, demonstrating enhanced catalytic activity, satisfactory stability and recyclability. Besides, by integration of AuCu@GOx and electrochromic material of Prussian blue, a sensitive and stable biosensing platform based on the excellent electrochromic property of Prussian blue and the enhanced enzyme activity of AuCu@GOx is developed, which enables the electrochemical and visual dual-mode detection of glucose. The as-constructed biosensing platform possesses a wide linear range, and good selectivity for glucose detection with a limit of detection of 0.82 μM in visual mode and 0.84 μM in electrochemical mode. This easy-to-operate biosensing platform opens a door for the practical application of the multi-mode strategy for glucose detection.

High-performance electrochemical detection of glucose in human blood serum using a hierarchical NiO2 nanostructure supported on phosphorus doped graphene

This report describes the development of high-performing non-enzymatic glucose sensors based on a combination of a phosphorous doped graphene (PG) layer and a composite metal oxide. Using a reflux technique and high-temperature annealing, a combined sheet-like NiO2@PG nanocomposite was created. This structure was examined using a variety of physicochemical methods, including thermogravimetric analysis, X-ray photoelectron spectroscopy, and scanning electron microscopy. The NiO2@PG nanocomposite offers a large surface area and an easily penetrable structure, allowing for greater chemical sensitivity to glucose oxidation. The dynamic range of the developed glucose sensor is relatively broad, ranging 10–170 μM. It exhibits a sensitivity of 70.28 μA μM−1 cm−2 , a small limit of detection of 7.83 μM, with a rapid response time of 1.07 s. The sensor also shows outstanding selectivity, long-term stability, reproducibility, and favorable repeatability, and can detect glucose in human serum samples. Additionally, the NiO2@PG composites sensing ability can be enhanced through ligand-to-metal charge-transfer, as validated by density functional theory. Studies on the mechanism of sensing and chemical structure of the composite after stabilization suggest it should prove useful in real-world applications.

Uniformly dispersing and anchoring graphene on GaN nanowire substrate: Application to electrochemical detection of glucose in sweat

For deposition of two-dimensional materials (e.g., graphene) on a substrate, self-aggregation and poor anchor strength are still issues. Herein, the GaN nanowire (NW) substrate was employed for electrochemical deposition of reduced graphene oxide (rGO) with satisfying dispersion uniformity and anchor strength. The deposited rGO exhibited flake morphology without agglomeration. Moreover, PtAu and rGO can be simultaneously and uniformly deposited on the GaN NW substrate to realize a PtAu–rGO/GaN electrochemical sensor for glucose detection. In comparison with deposition of PtAu–rGO on a stainless steel (SS) substrate (i.e., PtAu–rGO/SS), PtAu–rGO/GaN demonstrated much higher sensitivity and long-term stability, owing to better dispersion and anchor strength on GaN NW. In addition, with decoration of glucose oxidase (GOx), the GOx/PtAu–rGO/GaN sensor can be used for detecting glucose in human sweat with a low limit of detection of 5 μM, a wide linear detection range of 5 μM–12 mM, and high long-term stability, which indicates that GOx/PtAu–rGO/GaN sensor is promising for noninvasive glucose detection.

Two-Dimensional Copper/Nickel Metal-Organic Framework Nanosheets for Non-Enzymatic Electrochemical Glucose Detection.

Metal-organic frameworks (MOFs) have broad potential applications in electrochemical glucose detection. Herein, a green ultrasonic synthesis process is presented for preparing two-dimensional (2D) copper-nickel metal-organic framework nanosheets (CuNi-MOFNs) for glucose detection. The synthesized CuNi-MOFNs were characterized using scanning electron microscopy (SEM), scanning transmission electron microscope (STEM), X-ray diffractometer (XRD), and X-ray photoelectron spectrometer (XPS). The CuNi-MOFN nanocomposites were used to cover the glassy carbon electrode (GCE) and the CuNi-MOFNs-modified electrode was studied in alkaline media. Cyclic voltammetry (CV) and amperometric i-t curves indicated that the CuNi-MOFNs-modified electrode revealed great electrochemical performances towards glucose oxidation. Due to the ease of access to active metal sites in large specific surface of nanosheets, the CuNi-MOFNs-modified electrode can effectively improve the electronic transfer rate and enhance electrocatalytic activity of the CuNi-MOFNs-modified electrode. The CuNi-MOFNs-modified electrode showed electrochemical performances for glucose detection with a linear range from 0.01 mM to 4 mM, sensitivity of 702 μAmM-1cm-2, and detection limit of 3.33 μΜ (S/N = 3). The CuNi-MOFNs-modified electrode exhibited excellent anti-interference ability and high selectivity in glucose measurements. Hence, the CuNi-MOFNs-modified electrode has good, promising prospects in non-enzymatic electrochemical glucose detection.

Outstanding glucose sensing properties of N-doped carbon nanotubes boosted by Co(II) and Cu(II) ions in alkaline electrolytes

Electrochemical glucose detection co-catalyzed by bimetallic ions is carried out by introducing Co(II) and Cu(II) into the alkaline solution. The technique avoids the complicated electrode design and catalyst poisoning. By using nitrogen-doped carbon nanotubes (NCNT) loaded on carbon cloth (CC) as the working electrode, the bimetal co-catalytic system achieves a sensitivity of 6,909 mA M−1 cm−2, a detection limit of 0.4 μM (S/N = 3), as well as good selectivity and stability. By performing systematic electrochemical and structural analysis, the mechanism of Co(II) and Cu(II) co-catalysis for glucose detection in the solution is elucidated. Co(II) supplies the dynamic reaction sites and source of active intermediate (CoOOH), while Cu(II) promotes the formation of CoOOH. The results provide mechanistic insights into bimetal co-catalysis of glucose detection and other electrochemical reactions.

A sensitive, selective non-enzymatic electrochemical detection and kinetic study of glucose over Pt nanoparticles/SWCNTs/NiO ternary nanocomposite

BackgroundThe coupling of inorganic metal nanoparticles, semiconductor-based metal oxide nanostructures, and carbon nanomaterials is a promising strategy to fabricate efficient electrochemical sensors. Herein, we successfully designed a sensitive and selective electrochemical glucose sensor using Pt nanoparticles (PtNPs) decorated single-wall carbon nanotubes (SWCNTs) and nickel oxide (NiO) nanostructure-based composite materials. MethodsThe nanocomposite was synthesized without applying any dispersant or stabilizer using simple ultrasonication and photo-reduction techniques. Significant findingsThe morphology of nanocomposite reveals a homogenous dispersion of CNTs and PtNPs over the NiO nanostructure. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) demonstrated that the ternary nanocomposite-modified glassy carbon electrode (Pt@CNTs/NiO/GCE) displayed enhanced catalytic activity compared to CNTs/NiO/GCE, NiO/GCE or bare GGE electrodes. Kinetics studies indicated that the glucose electrooxidation using Pt@CNTs/NiO modified GCE followed irreversible diffusion-controlled kinetics with a transfer co-efficient value (α) ≈ 0.50. Amperometric sensing investigation revealed excellent sensitivity (149.36 µA mM−1 cm−2) and a lower limit of detection value (2.16 µM). The currently fabricated sensor electrode showed appropriate selectivity in the presence of various organic and inorganic species with outstanding repeatability, reproducibility, and sensor stability. The newly fabricated nanocomposite can represent a promising electro-catalyst for the efficient sensing of glucose and other biomolecules by the electrochemical approach.

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.

Non-enzymatic glucose detection using free-standing gold nanoparticle loaded carrageenan hydrogel electrodes

The current manuscript reports the development of free-standing nanomaterial-modified hydrogels that can be explored for sensing applications. Most of the nanomaterial-hydrogel systems developed till now rely on the modification of an electrode as the supporting substrate on which the electrochemical reactions can take place. These substrates can be pencil electrodes and or screen-printed electrodes. This widely limits the use of hydrogels which can be used as scaffolds and can be explored for the fabrication of free-standing electrodes. Since the functionality of only hydrogel is quite limited the current manuscript reports the loading of gold nanoparticles inside the hydrogel matrix which makes it functionally active. The successful synthesis of the modified hydrogel was confirmed with Scanning Electron Microscopy (SEM) and elemental analysis. The rheological data confirmed the positive effect of gold loading on the hydrogel storage modulus. As a proof of concept, the work reports the non-enzymatic electrochemical detection of glucose using gold nanoparticle loaded carrageenan hydrogel. The sensor showed a linear response towards varying glucose concentrations (0 to 2.5 mM). The hydrogel systems can be incorporated into wearables and implantable sensors and can be extended for the detection of other biomarkers in bodily fluids.

Ultrasmall platinum nanoclusters densely immobilized on hairy metal organic framework for nonenzymatic glucose detection

Rational design of non-enzymatic nanomaterials that possess the similar functions to natural enzymes holds great promise in chemical and biological molecule detection. In this work, a non-enzymatic electrochemical biosensor for detection of glucose was developed based on poly(2-vinylpyridine) (P2VP) grafted UiO-66 metal organic framework decorated with ultrafine platinum nanoclusters (PtNCs). The as-fabricated UiO-66-g-P2VP/PtNCs nanocomposite was then placed on an indium tin oxide (ITO) electrode to construct non-enzymatic glucose biosensor for electrochemical detection of glucose in alkaline electrolyte. The resulting UiO-66-g-P2VP/PtNCs/ITO modified electrode showed two linear responses over glucose concentration ranging of 0.01–5 mM and 5–18 mM with a low detection limit of 2.18 μM (S/N = 3). Moreover, the UiO-66-g-P2VP/PtNCs/ITO serving as an electrochemical biosensor was successfully applied to the rapid determination of glucose in human serum sample with a desirable result. Our findings pave the way for design and development of a promising artificial enzyme for the construction of high performance sensing platform.