Surface Selenylation Engineering for Construction of a Hierarchical NiSe2/Carbon Nanorod: A High-Performance Nonenzymatic Glucose Sensor

Controlled synthesized of ternary Cu-Co-Ni-S sulfides nanoporous network structure on carbon fiber paper: a superior catalytic electrode for highly-sensitive glucose sensing

BACKGROUND

Efficient monitoring of glucose concentration in the human body necessitates the utilization of electrochemically active sensing materials in nonenzymatic glucose sensors. However, prevailing limitations such as intricate fabrication processes, lower sensitivity, and instability impede their practical application. Herein, ternary Cu-Co-Ni-S sulfides nanoporous network structure was synthesized on carbon fiber paper (CP) by an ultrafast, facile, and controllable technique through on-step cyclic voltammetry, serving as a superior self-supporting catalytic electrode for the high-performance glucose sensor.

RESULTS

The direct growth of free-standing Cu-Co-Ni-S on the interconnected three-dimensional (3D) network of CP boosted the active site of the composites, improved ion diffusion kinetics, and significantly promoted the electron transfer rate. The multiple oxidation states and synergistic effects among Co, Ni, Cu, and S further promoted glucose electrooxidation. The well-architected Cu-Co-Ni-S/CP presented exceptional electrocatalytic properties for glucose with satisfied linearity of a broad range from 0.3 to 16,000 μM and high sensitivity of 6829 μA mM- 1 cm- 2. Furthermore, the novel sensor demonstrated excellent selectivity and storage stability, which could successfully evaluate the glucose levels in human serum. Notably, the novel Cu-Co-Ni-S/CP showed favorable biocompatibility, proving its potential for in vivo glucose monitoring.

CONCLUSION

The proposed 3D hierarchical morphology self-supported electrode sensor, which demonstrates appealing analysis behavior for glucose electrooxidation, holds great promise for the next generation of high-performance glucose sensors.

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.

Microplasma and quenching-induced Co doped NiMoO4 nanorods with oxygen vacancies for electrochemical determination of glucose in food and serum

In this paper, Co-doped NiMoO₄ nanorods with oxygen vacancies are synthesized on carbon cloth (Co-NiMoO₄ NRs/CC) via microplasma and quenching-induced method.Owing to the surface defects and metal ion doping, the electronic structure and surface properties of the catalyst are tuned.Cyclic voltammetry (CV) and amperometry are used to investigate the electrocatalytic behavior of the glucose sensor in an alkaline medium with sensitivities of 7411 and 3125 μA L mmol^-1 cm^-2 in the linear range 1.0 μmol L^-1 to 1.0 mmol L^-1 and 1.0 mmol L^-1 to 7.0 mmol L^-1, respectively. The detection limit is 0.079 μmol L^-1 at S/N = 3. Moreover, the as-prepared catalyst electrode is also successfully used in real food and serum samples, with a recovery rate of 97.1%-107.4%.The DFT calculations show that the Co site of the catalyst significantly influenced glucose sensing performance. This idea expands the application of quenching chemistry in electrochemical sensing.

Metal-organic frameworks (MOFs) based luminescent and electrochemical sensors for food contaminant detection

With the increasing population, food toxicity has become a prevalent concern due to the growing contaminants of food products. Therefore, the need for new materials for toxicant detection and food quality monitoring will always be in demand. Metal-organic frameworks (MOFs) based on luminescence and electrochemical sensors with tunable porosity and active surface area are promising materials for food contaminants monitoring. This review summarizes and studies the most recent progress on MOF sensors for detecting food contaminants such as pesticides, antibiotics, toxins, biomolecules, and ionic species. First, with the introduction of MOFs, food contaminants and materials for toxicants detection are discussed. Then the insights into the MOFs as emerging materials for sensing applications with luminescent and electrochemical properties, signal changes, and sensing mechanisms are discussed. Next, recent advances in luminescent and electrochemical MOFs food sensors and their sensitivity, selectivity, and capacities for common food toxicants are summarized. Further, the challenges and outlooks are discussed for providing a new pathway for MOF food contaminant detection tools. Overall, a timely source of information on advanced MOF materials provides materials for next-generation food sensors.

Electronic structure engineering on NiSe2 micro-octahedra via nitrogen doping enabling long cycle life magnesium ion batteries

Multivalent ion batteries have attracted great attention because of their abundant reserves, low cost and high safety. Among them, magnesium ion batteries (MIBs) have been regarded as a promising alternative for large-scale energy storage device owing to its high volumetric capacities and unfavorable dendrite formation. However, the strong interaction between Mg²⁺ and electrolyte as well as cathode material results in very slow insertion and diffusion kinetics. Therefore, it is highly necessary to develop high-performance cathode materials compatible with electrolyte for MIBs. Herein, the electronic structure of NiSe₂ micro-octahedra was modulated by nitrogen doping (N-NiSe₂) through hydrothermal method followed by a pyrolysis process and this N-NiSe₂ micro-octahedra was used as cathode materials for MIBs. It is worth noting that N-NiSe₂ micro-octahedra shows more redox active sites and faster Mg²⁺ diffusion kinetics compared with NiSe₂ micro-octahedra without nitrogen doping. Moreover, the density functional theory (DFT) calculations indicated that the doping of nitrogen could improve the conductivity of active materials on the one hand, facilitating Mg²⁺ ion diffusion kinetics, and on the other hand, nitrogen dopant sites could provide more Mg²⁺ adsorption sites. As a result, the N-NiSe₂ micro-octahedra cathode exhibits a high reversible discharge capacity of 169 mAh g^-1 at the current density of 50 mA g^-1, and a good cycling stability over 500 cycles with a maintained discharge capacity of 158.5 mAh g^-1. This work provides a new idea to improve the electrochemical performance of cathode materials for MIBs by the introduction of heteroatom dopant.

Morphology Control Strategy of Bimetallic MOF Nanosheets for Upgrading the Sensitivity of Noninvasive Glucose Detection

The precise measurement of glucose level is significant for the health management of the human body. However, the existing sensitive materials and detection methods for glucose are less satisfying for practical applications. Herein, an ultrathin reticular two-dimensional nanosheets array composed of trimesic acid (H₃BTC)-based bimetal metal-organic frameworks (MOFs) and carbon cloth (CC), which is constructed through a morphology control strategy, is reported for glucose sensing. Meanwhile, this nonmoving sweat glucose sensor based on a NiCo-BTC/CC electrode has been successfully prepared by a screen printing method. Benefiting from the regular and ultrathin nanosheets array, the NiCo-BTC/CC electrode has an excellent sensitivity of 2701.29 μA mM^-1 cm^-2, which is about 2.4 times that of its unregulated counterpart (1127.85 μA mM^-1 cm^-2) in the linear range 5-205 μM. In addition, an ultralow detection limit (0.09 μM, S/N = 3) and good selectivity of NiCo-BTC/CC were also obtained. The high sensitivity of the glucose sensor based on NiCo-BTC/CC electrode is 0.174 μA μM^-1 (50-1000 μM). Remarkably, the preciously designed sensor is used to detect glucose concentration in sweat with a noninvasive mode, and the results are basically consistent with those of a commercial glucose device with an invasive mode. This research exhibits potential methodology for the morphology design of bimetallic MOFs nanosheets to achieve a high accuracy rate and noninvasive and timeless measurement of a glucose sensor.

High-Performance Three-Dimensional Spongin-Atacamite Biocomposite for Electrochemical Nonenzymatic Glucose Sensing

The design of sensitive and cost-effective biocomposite materials with high catalytic activity for the effective electrooxidation of glucose plays a key role in developing enzyme-free glucose sensors. The porous three-dimensional (3D) spongin scaffold of marine sponge origin provides an excellent template for the growth of atacamite crystals and improves the activity of atacamite as a catalyst. By using the design of experiment method, the influence of different parameters on the electrode efficiency was optimized. The optimized sensor based on spongin-atacamite showed distinguished performance toward glucose with two linear ranges of 0.4-200 μM and 0.2-10 mM and high sensitivities of 3908.4 and 600.5 μA mM^-1 cm^-2, respectively. Importantly, the designed sensor exhibited strong selectivity and favorable stability, reproducibility, and repeatability. The performance in the real application was estimated by glucose detection in spiked human blood serum samples, which verified its great potential as a reliable platform for enzyme-free glucose sensing.