Detection Of Glucose Concentration Research Articles

An integrated plant glucose monitoring system based on microneedle-enabled electrochemical sensor

Real-time monitoring of glucose concentration changes in plants and access to plant physiological information timely are of great significance to the development of precision agriculture. Here, we innovatively present an electrochemical sensing device that combines microneedle sensors and 3D printing technology to achieve real-time monitoring of glucose in plants in a minimally invasive manner. The device consists of two components: the inner part features a highly efficient sensing interface based on platinum wire (MPt-Au-Nafion-GOx-Pu), while the outer part consists of polymer microneedles formed by 3D printing. Additionally, the polymer hollow microneedle features a slender tip diameter of only 300 μm, minimizing plant damage during the detection procedure. The device shows good detection performance, with a limit of detection (LOD) of 33.3 μM and a detection sensitivity of 17 nA/μM·cm2. It can detect glucose concentrations in the range of 100 μM to 100 mM, providing a unique solution for timely agronomic management of crops tool. By performing 12 h real-time monitoring and salt stress treat on tomato and aloe vera, the results verified the feasibility of integrated device applied to real-time glucose detection in plants.

Glucose Biosensors - State of the Art and Prospects

Rapid glucose concentration detection in technical and biological systems is an important scientific and technical task of modern chemistry, engineering and technology. The article provides an overview of the last technical solutions in this area. The issues of developing first generation biosensors are considered. However, the main disadvantage of such systems was the significant influence of ascorbic and uric acids on the generated signal, which significantly reduced their selectivity and accuracy. To solve this problem, it is possible to use ion-selective membranes such as Nafion and polycarbonate. The second generation of glucose biosensors uses artificial mediators to facilitate electron transfer between the enzyme and the electrode. These mediators can be immobilized directly by the enzyme or introduced into an enzyme-modified electrode. Suitable mediators include conducting organic salts, ferrocene, quinone compounds, ferricyanide, transition metal complexes, phenothiazine and foxazine compounds. Effective interactions between enzymes and mediators are critical for efficient electron transport. Various approaches have been proposed to tailor mediators, such as the use of Os complexes, noncovalent functionalization of carbon nanotubes, and stabilization of artificial mediators. The third generation of enzyme glucose biosensors uses direct electron transfer to perform electrochemical reduction. Various approaches have been considered, including reassembling apoproteins on cofactor-modified enzymes and electrically coupling enzymes to electrode surfaces using redox polymers or nanomaterials such as gold nanoparticles. Such approaches ensure the formation of an effective enzyme-electrode bond. In addition, the thickness of the enzymatic layer can affect the performance of the biosensor. External factors such as temperature, pH and humidity can have a significant impact on the performance of such electrodes.

Temperature compensation measurements in the detection of glucose and sodium chloride solution concentration based on SPR in the optical fiber

The temperature variation is one of the main error factors in the process of glucose and sodium chloride solution concentrations detection based on optical fiber sensor. In this paper, we proposed a sensor with temperature compensation, which can detect the temperature while measuring the concentrations of glucose or sodium chloride solution. The dual-channel design enables the sensor to obtain accurate measurement results of glucose and sodium chloride concentrations, and also to monitor the environmental temperature simultaneously. The deposition of zinc oxide film not only enhances the sensitivity of the sensor but also prevents oxidation of the silver film. The high stability of polydimethylsiloxane (PDMS) ensures that the two sensing channels of the sensor do not interfere with each other. The proposed dual-channel sensor offers advantages of low cost, a simple structure, and high sensitivity, with potential applications in the fields of food science and biochemistry.

Self-Adhesive, Biocompatible, Wearable Microfluidics with Erasable Liquid Metal Plasmonic Hotspots for Glucose Detection in Sweat.

Sweat is a noninvasive metabolite that can provide clinically meaningful information about physical conditions without harming the body. Glucose, a vital component in sweat, is closely related to blood glucose levels, and changes in its concentration can reflect the health status of diabetics. We introduce a self-adhesive, wearable microfluidic chip with erasable liquid metal plasmonic hotspots for the precise detection of glucose concentration in sweat. The self-adhesive, wearable microfluidic chip is made from modified polydimethylsiloxane (PDMS) with enhanced stickiness, enabling conformal contact with the skin, and can collect, deliver, and store sweat. The plasmonic hotspots are located inside the microfluidic channel, are generated by synthesizing silver nanostructures on liquid metal, and can be removed in the alkaline solution. It indicates the erasable and reproducible nature of the plasmonic hotspots. The detection method is based on surface-enhanced Raman spectroscopy (SERS), which allows for accurate detection of the glucose concentration. To enhance the sensitive detection of glucose, the SERS substrate is modified by 4-mercaptophenylboronic acid to achieve the limit of detection of 1 ng/L glucose, which is much lower than the physiological conditions (7.2-25.2 μg/L). The developed microfluidic chip is soft, stretchable, and nontoxic, bringing new possibilities to wearable sweat-sensing devices.

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.

High linearity temperature-compensated SPR fiber sensor for the detection of glucose solution concentrations

In the realm of optical fiber sensing, conventional surface plasmon resonance (SPR) sensors often face challenges due to their low linearity, broad resonance, and susceptibility to external temperature changes. To that end, we evaluate a groundbreaking approach with a temperature-compensating SPR biosensor based on the Mach-Zehnder interferometer (MZI), featuring a novel tapered multimode fiber-single mode fiber-multimode fiber (MMF-SMF-MMF) architecture. Specifically, the SPR is excited on a silver film modified by reduced graphene oxide (rGO) and π-π stacked pyrene-1-boric acid providing specific glucose binding ability. The MZI effect compensating for ambient temperature influence on the SPR is realized with the MMF-SMF-MMF structure. The study also explores the use of Fast Fourier Transform (FFT) for separate, granular analysis of the MZI and SPR signals and improves the linearity of the sensor using a novel centroid-fitting technique. This method utilizes the shift of calculated centroid coordinates rather than the single dip resonance wavelength from SPR, enhancing the overall performance of the sensor. The experimental results demonstrate excellent glucose sensitivity of 2.819 nm/mM, a linear range of 0–10 mmol/L, a LOD of 0.12 mM/L and concurrent temperature compensation. Compact and easy to fabricate, the proposed SPR sensor provides a novel solution for accurate glucose concentration detection in human blood.

Co-MOF@GO nanotubes constructed from nickel foam loaded with Co(OH)2: A non-enzymatic high-performance electrochemical sensor for glucose

The construction and development of enzyme-free sensors made of non-precious metals that are extremely sensitive to glucose is of great importance for treatment of diabetes. A room temperature reaction method was used to grow ZIF-67@GO nanocubes on nickel foam substrates, followed by a hydrothermal method to construct Co(OH)2 nanomaterials. From this NF/ZIF-67@GO/Co(OH)2 enzyme-free glucose sensor with a unique structure was designed. The results and the charge transfer process of glucose's catalytic oxidation detection were systematically investigated in the composite material. The experimental results show that this sensor exhibits good electrochemical activity for glucose detection. It has a linear range of 0.1 μM-8.546 mM, a very high sensitivity of 2412.7 μA mM−1 cm−2, and its low detection limit is 0.934 M (signal-to-noise ratio of 3). These results indicate that the sensor is capable of accurately and sensitively detecting glucose concentration and has great potential for use in practical applications. The synthesis method is simple, fast, low-cost and easy to apply to electrochemical electrodes. Besides, the material has reproducibility, stability and good selectivity.

Theoretical study of a Janus layered photonic structures based on improved particle swarm algorithm for detection of serum creatinine and glucose concentration

An improved particle swarm optimization (IPSO) algorithm is proposed to perform parameter optimization of the sensor which is realized by Janus layered photonic structures (LPS) based on the optical Tamm state (OTS) and defect layer, which can be used to detect serum creatinine (SCR) solution concentration (CSCR ) and glucose solution concentration (CG ) by adjusting the thickness and refractive index (RI) of the medium in the structure to control the peak and frequency changes of the transmission and absorption peaks. Due to the characteristic of Janus, the light incident from different directions can produce different effects. The OTS based on metal properties has sensitive and narrow absorption peaks when the light comes in forward propagation, its absorption characteristics allowing accurate measurement of CSCR with a high sensitivity (S) of 172 THz/RIU and a relevant quality factor (Q) of 651 and a lower detection limit (DL) of 2.3163 × 10−4. It has a significant Q of 4.5 × 104, DL of 4.825 × 10−5, and S of 11.7857 THz/RIU with its transmission characteristics which can be used to detect CG when the light comes in backward propagation. It can be said that the IPSO has a certain application prospect for the design of optical sensing.

A nonenzymic microfiber optic-biosensor modified phenylboric acid for sensitively and specifically detecting low glucose concentration

A microfiber interferometer coated with sensitive films formed by amide bond between 3-Carboxy-4-fluorophenylboronic acid (FPBA) and polydopamine (PDA) for the detection of trace glucose concentration is designed and demonstrated. Due to a huge evanescent field, this microfiber interferometer has a very sensitive response to the refractive index (RI) of the surrounding environment, which has excellent sensing performance including RI sensitivity response of 1825.83 nm/RIU and low temperature response of −0.04 nm/°C. Due to the good film-forming performance of PDA, whose the amino group coupled with the carboxyl molecule on FPBA to form an amide bond, PDA/FPBA can be attached to the microfiber interferometer for detecting different concentrations of glucose. The concentration range of glucose detection is 0.1–20 mM with a sensitivity of 1.71 nm/mM and a limit of detection of 12.6 ppm. Finally, the sensor is tested in actual samples of human urine to detect different concentrations of glucose and proved to be responsive and reproducible in urine. We can estimate the concentration of glucose in urine by wavelength shift. The sensor has the advantages of simple manufacture, low cost, high sensitivity, and specific recognition glucose in urine. In addition, the success of this sensor shows that the combination of ultrafine fiber and organic chemical materials has broad prospects in the field of optical detection.

Self-regulating bioinspired supramolecular photonic hydrogels based on chemical reaction networks for monitoring activities of enzymes and biofuels

Inspired by the way many living organisms utilize chemical/biological reactions to regulate their skin and respond to stimuli in the external environment, we have developed a self-regulating hydrogel design by incorporating chemical reaction networks (CRNs) into biomimetic photonic crystal hydrogels. In this hydrogel system, we used host–guest supramolecular non-covalent bonds between beta-cyclodextrin (β-CD) and ferrocene (Fc) as partial crosslinkers and designed a CRN involving enzyme-fuel couples of horseradish peroxidase (HRP)/H2O2 and glucose oxidase (GOD)/d-glucose, by which the responsive hydrogel was transformed into a glucose-driven self-regulating hydrogel. Due to the biomimetic structural color in the hydrogel, the progress of the chemical reaction was accompanied by a change in the color of the hydrogel. Based on this principle, the designed supramolecular photonic hydrogel (SPH) can not only achieve naked-eye detection of H2O2 and glucose concentrations with the assistance of a smartphone but also monitor the reactions of HRP and GOD enzymes and determine their activity parameters. The sensitivity and stability of the sensor have been proven. In addition, due to the reversibility of the chemical reaction network, the sensor can be reused, thus having the potential to serve as a low-cost point-of-care sensor. The SPH was ultimately used to detect glucose in human plasma and H2O2 in liver tumor tissue. The results are comparable with commercial assay kits. By redesigning the chemical reaction network in the hydrogel, it is expected to be used for detecting other enzymes or fuels.

Prism SPR Glucose Sensor Based on Gold Nanoparticle/Gold Film Coupling Enhanced SPR

A novel glucose sensor based on gold nanoparticles (AuNPs) enhanced surface plasmon resonance (SPR) is proposed for the accurate detection of glucose concentration. The coupling enhancement effect of localized surface plasmon resonance (LSPR) of AuNPs and SPR of gold film can improve the refractive index sensitivity of the sensor. The specific reaction between glucose and glucose oxidase (GOD) causes a change in the refractive index of the glucose solution microenvironment and eventually leads to a drift in the resonance angle. Field emission scanning electron microscopy (SEM) was used to characterize the GOD before and after immobilization, and the effect of different concentrations of GOD on the detection of glucose by the sensor was investigated. The experimental results showed that the proposed sensor surface out excellent performance in terms of sensitivity (0.8633 degree/(mg/ml)).

A plastic optic fiber sensor with temperature compensation for refractive index measurement

An optical fiber sensor based on a gradually hot-pressed flatted plastic optical fiber (POF) and F-P interference structure is proposed to eliminate the effect of ambient temperature drift in the refractive index (RI) detection of glucose concentration. Based on the analysis of the influence of the sensor itself and the RI change of solution on the transmitted light intensity under the effect of temperature, a self-calibration formula was established by means of the peak wavelength and the transmitted light intensity of interference peak were used as information carriers to calibrate the parameters. The results of the validation show that the temperature drift compensation method proposed in this paper is feasible. The maximum relative error between the measured RI after compensation and actual value is only 0.032%, and it has good repeatability. The precision to the RI with temperature compensation of the gradually hot-pressed flatted POF and F-P interference structure has potential applications in the biochemistry, medical diagnosis, and environmental monitoring.

Polyaniline-graphite on cellulose substrate: a flexible, low-cost, use-and-throw sensor for glucose concentration detection

Polyaniline-graphite on cellulose substrate: a flexible, low-cost, use-and-throw sensor for glucose concentration detection

Development of an electrochemical sensor for simultaneous determination of glucose and insulin: Application for accurate classification of diabetes mellitus

Diabetes mellitus is a chronic metabolic disorder characterized by high blood glucose levels, resulting from defects in insulin secretion, insulin action, or both. Accurate and sensitive detection of glucose and insulin concentrations is crucial for the effective management and diagnosis of diabetes. Current techniques for glucose and insulin detection, such as enzyme-linked immunosorbent assay (ELISA) and glucose oxidase-based methods, have limitations including complex procedures, high costs, and insufficient selectivity. In this paper, we report the development of a coupled electrochemical sensor for the simultaneous detection of glucose and insulin concentrations, enabling classification of diabetes mellitus. The sensor is based on a modified electrode, NC-A/GCE, which demonstrates high sensitivity and selectivity towards both analytes. We utilize differential pulse voltammetry (DPV) and chronoamperometry techniques for quantitative analysis and demonstrate the sensor's potential for accurate diabetes classification through a large dataset of detection data.

Characterization of starvation response-related genes for predicting prognosis in breast cancer.

Breast cancer (BRCA) cells typically exist in nutrient-deficient microenvironments and quickly adapt to states with fluctuating nutrient levels. The tumor microenvironment of starvation is intensely related to metabolism and the malignant progression of BRCA. However, the potential molecular mechanism has not been thoroughly scrutinized. As a result, this study aimed to dissect the prognostic implications of mRNAs involved in the starvation response and construct a signature for forecasting the outcomes of BRCA. In this research, we investigated how starvation could affect BRCA cells' propensities for invasion and migration. The effects of autophagy and glucose metabolism mediated by starved stimulation were examined through transwell assays, western blot, and the detection of glucose concentration. A starvation response-related gene (SRRG) signature was ultimately generated by integrated analysis. The risk score was recognized as an independent risk indicator. The nomogram and calibration curves revealed that the model had excellent prediction accuracy. Functional enrichment analysis indicated this signature was significantly enriched in metabolic-related pathways and energy stress-related biological processes. Furthermore, phosphorylated protein expression of the model core gene EIF2AK3 increased after the stimulus of starvation, and EIF2AK3 may play an essential role in the progression of BRCA in the starved microenvironment. To sum up, we constructed and validated a novel SRRG signature that could accurately predict outcomes and may be developed as a therapeutic target for the precise treatment of BRCA.

RF-LqRNN:RFID-Based Concentration Detection of Alcohol Solutions and Glucose Solutions

Solution concentration detection plays an important role in many real-life applications. For example, alcohol concentration detection can prevent cases where low-concentration liquor red is used to replace high-concentration liquor, while glucose concentration detection can be used to prevent diabetes. In this paper, the RF-LqRNN system is proposed, which can classify solution concentrations using an inexpensive commercial off-the-shelf radio frequency identification device. The proposed system uses the feature that the phase and RSSI of radio frequency signals across solutions of different concentrations are different. Measurements of the two features were obtained at different concentrations and input into a GRU-RNN to train a solution concentration classification model. The experimental results show that 98.5% classification accuracy can be achieved for 10 alcohol solution concentrations, and 97.3% classification accuracy can be achieved for 10 glucose solution concentrations. The effects of ceramic, glass, paper and plastic containers on solution concentration classification are also investigated, and it is determined that the solution concentration classification accuracy is the lowest in ceramic containers and the highest in plastic containers. Even at the lowest accuracies achieved in ceramic containers, the proposed method achieves more than 94% in the classification of the concentration of alcohol and glucose solutions.

One-dimensional photonic crystal-based biosensor for the detection of glucose concentration in human urine

A biosensor structure based on a ternary photonic crystal (TPC) containing a defect is designed and simulated. This proposed biosensor detects the concentration of glucose in human urine. Based on the transfer matrix method, we theoretically studied the transmission spectra through the TPC presuming blood samples with different refractive indices (RIs) infiltrated into the defect layer of the proposed structures. By varying the concentration of glucose in the urine, the RI of the urine is changed, which in turn changes the sensor’s output response; both transmission response and resonance wavelength are affected. We evaluated average sensitivity (S) for the number of periods at different values N for optimization purposes. Our results show that the biosensor has performance parameters for a period value N = 6. Indeed, a value of 1033 nm of full width at half maximum photonic bandgap can be observed with a S of 965 nm / RIU. The quality factor is 1892.542 and the figure of merit is 756.86 RIU − 1. The proposed biosensor can be a miniaturized structure with extreme sensitivity in the concentration of glucose detection models

Surface enhanced Raman scattering active substrate based on hydrogel microspheres for pretreatment-free detection of glucose in biological samples

Determining glucose in biological samples is tedious and time-consuming due to sample pretreatment. The sample is usually pretreated to remove lipids, proteins, hemocytes and other sugars that interfere with glucose detection. A surface-enhanced Raman scattering (SERS) active substrate based on hydrogel microspheres has been developed to detect glucose in biological samples. Due to the specific catalytic action of glucose oxidase (GOX), the high selectivity of detection is guaranteed. The hydrogel substrate prepared by microfluidic droplets technology protects the silver nanoparticles from the surrounding environment and improves the stability and reproducibility of the assay. In addition, the hydrogel microspheres have size-adjustable pores that selectively allow small molecules to pass through. The pores block the entry of large molecules, such as impurities, enabling glucose detection through glucose oxidase etching without sample pretreatment. This hydrogel microsphere-SERS platform is highly sensitive and enables reproducible detection of different glucose concentrations in biological samples. The use of SERS to detect glucose provides clinicians with new diagnostic methods for diabetes and a new application opportunity for SERS-based molecular detection techniques.

A planar microwave sensor for noninvasive detection of glucose concentration using regression analysis

AbstractThis paper presents a planar microwave sensor for the noninvasive detection of glucose concentration in diabetic patients. The designed sensor operates from the 3.8 to 6.2 GHz frequency band, which covers the 5.8 GHz Industrial Scientific and Medical (ISM) band. The designed sensor shows a percentage bandwidth of 23.8% with a reflection coefficient (S11) of −50 dB at the resonance frequency of 5.7 GHz. The detection was carried out by varying the relative permittivity of the blood in accordance with the glucose concentration based on the Cole–Cole model. The measured result is calculated in terms of varying resonance frequency with variation in the reflection coefficient |S11| of the designed sensor. The observed frequency shift and corresponding sensitivity of the sensor are found at 1.7 GHz and 0.089 MHz/mg dL−1, respectively. An experimental validation has also been performed, and the frequency shift is analyzed by interacting the human thumb with the sensor. The simulated and experimental results of the designed sensor suggest that it can be useful for detecting glucose concentration noninvasively for diabetic patients.

Self-powered triboelectric sensor with N-doped graphene quantum dots decorated polyaniline layer for non-invasive glucose monitoring in human sweat

A novel non-invasive wearable self-powered triboelectric sensor (TES) for simultaneous physiological monitoring had shed the light on its extraordinary performance, which become a promising choice for detecting glucose concentration from human sweat via non-invasive strategy. For realizing the function of wearable TES, the flexible substrate of conducting polymers commonly served as matrix for not only immobilizing the specific enzyme, but also played as the sensing layer by the coupling effect of triboelectrification/enzymatic reaction. To boost up the reliability and sensitivity of conducting polymer-based TES, in this study, a nanocomposite of N-doped graphene quantum dots decorated polyaniline (NGQDs/PANI) is designed as a triboelectric layer for non-invasive glucose detection. The surface electronegativity of PANI was changed by decorating the NGQDs with electron-rich functional groups for increasing the surface charge, which further facilitating the charge transfer between the PANI and intermedia and then enhancing triboelectric outputs. Upon the enhanced electron transfer and surface charge by NGQDs, NGQDs/PANI/GOx based TES offers greater sensitivity (23.52 mM−1) in glucose detection compared to pristine PANI/GOx one (16.44 mM−1). Notably, this study demonstrates the feasibility of wearable TES on human skin and their reliable and sensitive performance with a self-driving system without any external power source.