Glucose Detection Research Articles

Self-assembly of cascade nanoenzyme glucose oxidase encapsulated in copper benzenedicarboxylate for wearable sweat-glucose colorimetric sensors with smartphone readout

BackgroundWith the advent of personalized medical approaches, precise and tailored treatments are expected to become widely accepted for the prevention and treatment of diabetes. Paper-based colorimetric sensors that function in combination with smartphones have been rapidly developed in recent years because it does not require additional equipment and is inexpensive and easy to perform. In this study, we developed a portable, low-cost, and wearable sweat-glucose detection device for in situ detection. ResultsThe sensor adopted an integrated biomimetic nanoenzyme of glucose oxidase (GOx) encapsulated in copper 1, 4-benzenedicarboxylate (CuBDC) (GOx@CuBDC) through a biomimetic mineralization process. CuBDC exhibited a peroxide-like effect, cascade catalytic effect with the encapsulated GOx, and increased the enzyme stability. GOx@CuBDC and 3,3,5,5-tetramethylbenzidine were combined to form a hybrid membrane that achieved single-step paper-based glucose detection. Significance and noveltyThis GOx@CuBDC-based colorimetric glucose sensor was used to quantitatively analyze the sweat-glucose concentration with smartphone readings. The sensor exhibited a good linear relationship over the concentration range of 40–900 μM and a limit of detection of 20.7 μM (S/N = 3). Moreover, the sensor performed well in situ monitoring and in evaluating variations based on the consumption of foods with different glycemic indices. Therefore, the fabricated wearable sweat-glucose sensors exhibited optimal practical application performance.

CoMnS@rGO nanocomposite grown on NF for high-performance supercapacitor-battery hybrid device and advancing electrochemical sensitivity

The co-electrodeposition approach has been widely used to synthesize the transition metal sulfides/oxides because of remarkable performance of the energy storage devices. In this research, cobalt manganese sulfide (CoMnS) binary compounds are synthesized using the co-electrodeposition approach. The main objective is to investigate the optimal number of depositing periods in cyclic voltammetry while maintaining a constant scan rate. The electrodes without binders are produced using a rapid synthesis approach, which involves assessing binary metal sulfide to achieve a significantly enhanced energy storage capacity. Further, the rGO is incorporated into the CoMnS to enhance the electrochemical properties. The CoMnS@rGO electrode showed the specific capacitance (Cs) of 2357 F/g because of the small equivalent series resistance values as determined through electrochemical impedance spectroscopy (EIS) measurement, indicating a higher level of conductivity. The hybrid electrode showed high values of energy and power densities of 50.8 Wh/kg and 3440 W/kg, respectively. Besides, the nanocomposite electrode is used as a chemical sensor and precisely detects the multiple elements. The estimated value of R2 is 0.994 because of the high sensitivity. The hybrid electrode showed a signal-to-noise ratio (S/N) of 5. Furthermore, based on four observations, the comparative standard deviation (RSD) is calculated to be 1.9 %. The device showed high electrochemical glucose detection sensitivity. The nanocomposite-based electrodes provide a platform for designing novel multifunctional devices.

Colorimetric Glucose Biosensor Based on Chitosan Films and Its Application for Glucose Detection in Beverages Using a Smartphone Application.

Nowadays, biosensors are gaining increasing interest in foods' and beverages' quality control, owing to their economic production, enhanced sensitivity, specificity, and faster analysis. In particular, colorimetric biosensors can be combined with color recognition applications on smartphones for the detection of analytes, rendering the whole procedure more applicable in everyday life. Herein, chitosan (CS) films were prepared with the deep eutectic solvent (DES) choline chloride/urea/glycerol (ChCl:U:Gly). Glucose oxidase (GOx), a widely utilized enzyme in quality control, was immobilized within CS films through glutaraldehyde (GA), leading to the formation of CS/GOx films. The optimized GOx concentration and DES content were determined for the films. Moreover, the effect of the pH and temperature of the glucose oxidation reaction on the enzymatic activity of GOx was studied. The structure, stability, and specificity of the CS/GOx films as well as the Km values of free and immobilized GOx were also determined. Finally, the analytical performance of the films was studied by using both a spectrophotometer and a color recognition application on a smartphone. The results demonstrated that the films were highly accurate, specific to glucose, and stable when stored at 4 °C for 4 weeks and when reused 10 times, without evident activity loss. Furthermore, the films displayed a good linear response range (0.1-0.8 mM) and a good limit of detection (LOD, 33 μM), thus being appropriate for the estimation of glucose concentration in real samples through a smartphone application.

Detection and intelligent optimization of blood glucose signals based on MXene-assisted sensors

Two-dimensional materials exhibit unique properties that make them ideal for electronic sensing applications, particularly in the field of biosensors. In this study, a Ti3C2Tx MXene/graphene composite was investigated for its potential use in non-invasive blood glucose detection. The strong electrostatic interaction between MXene and graphene nanosheets effectively reduces the self-stacking of both components, resulting in the formation of a porous interlayer structure with enlarged interlayer spacing. This unique structure creates an efficient nanoscale transport channel, which increases the number of active sites and shortens ion diffusion paths. Consequently, the electrochemical properties of the composite membrane are enhanced, making it a promising candidate for sensing element applications. As the human blood glucose level is primarily determined by the glucose concentration in the blood, the concentration of glucose solution serves as the foundation for noninvasive blood glucose concentration detection. In this work, a prediction model was established using the partial least squares fitting method to correlate the electrochemical fingerprinting data with the glucose aqueous solution concentration, and the reliability of the model was verified. To address the limitations of the partial least squares method, which lacks nonlinear fitting capabilities, an RBF (radial basis function) network model was employed. Finally, a genetic algorithm was utilized to perform global optimization of the training parameters of the RBF network, and the quantitative relationship between the NIR spectral data and glucose concentration was validated. The findings of this study provide a theoretical basis for the development of equipment and the improvement of measurement accuracy in the field of human noninvasive glucose detection.

A novel strategy towards the fabrication of highly stable and sensitive non-enzymatic glucose sensor based on Ni3N thin films using high power impulse magnetron sputtering

Glucose level surveillance in mankind is considered the greatest need of recent times to achieve healthy lifestyle goals due to its health-related concern for humans. To fulfill the need, Nickel-based compounds emerge with excellent bio-mimic properties. However, due to the poor electrical properties of oxides and hydroxides of Ni, developing a supporting base that can enhance electron transportation is mandatory. The present work is dedicated to non-enzymatic glucose detection by electrochemical means on the Ni3N thin film on an Indium-doped Tin Oxide (ITO) substrate as a working electrode in an alkaline medium. The Ni3N films use HiPIMS as a deposition technique due to its high ionization rate of sputtered species and dense plasma which helps the Ni ions to react with nitrogen in the formation of a perfect Ni3N phase, and it is a green process that can contribute to sustainable manufacturing. Ni3N thin film deposited at a 60 % N2 flow ratio shows the largest crystallinity and catalytic properties, which helps this modified electrode to have significant potential for glucose detection. The Ni3N modified electrode acquires a lower linear range of 0.001–1.25 mM with sensitivity and Limit of Detection (LOD) of 337.46 µAmM–1cm−2, and 0.78 µM, respectively, and a higher linear range of 1.25–7.3161 mM with a sensitivity of 158.58 µAmM–1cm−2. The amperometric measurements reveal the fast response of the electrode towards glucose detection at 2.46 secs. The key measures of the electrode according to the corresponding measurements are satisfactory selectivity, reproducibility, repeatability, and operational stability. The modified electrode shows a significant response for real samples such as commercially available honey, apple juice, and biological fluids.

Non-Destructive Sensor for Glucose Solution Concentration Detection Using Electromagnetic Technology.

In this paper, a sensor using a complementary split ring resonator (CSRR) is proposed for non-destructive testing of blood glucose. By depicting the complementary split ring structure on the ground, the electromagnetic field strength between the split rings can be enhanced effectively. The structure size of the sensor by CSRR is determined by simulation, so that the insertion loss curve of the device has a resonance point at the frequency of 3.419 GHz. With a special holder created by three-dimensional (3D) printing technology, the test platform was established when the concentration of the solution varied from 0 mg/mL to 20 mg/mL. The experimental results indicate that there is an obvious linear relationship between the insertion loss S21 and the glucose concentration at the resonant frequency. Similarly, the measured real part and imaginary part of the S21 both vary with glucose concentration linearly. Based on the above experimental results, the feasibility of the sensor using a CSRR proposed in this paper for non-destructive detection of blood glucose is preliminarily verified.

Nano-Structured CuO Grown with Aqueous NH3 for Salivary Glucose Detection

CuO nanostructures grown on flexible Cu foil by a simple chemical bath deposition in a solution of aqueous ammonia have been explored for non-invasive and nonenzymatic detection of salivary glucose. The nanostructured electrode developed with 100 μl of aqueous ammonia achieves a high sensitivity of 3243 μA mM−1 cm−2, linear range up to 3 mM, and limit of detection of 0.77 μM. The electrode also demonstrates good anti-interference properties, high reproducibility, repeatability, and long-term stability up to 30 days. In addition, the electrode exhibits remarkable sensitivity of 2865 μA mM−1 cm−2 for salivary glucose detection. To explore its potential for non-invasive detection of actual salivary glucose, pre-prandial and post-prandial salivary glucose of different human volunteers were measured using the electrode and were found to be correlated with corresponding blood glucose levels. Development and investigation of similar sensors for non-invasive detection via untraditional methods would certainly pave the way towards next generation glucose monitoring devices and systems.

Sustainable Synthesis of CuO Nanoparticles for Colorimetric Detection of Hydrogen Peroxide and Glucose

Sustainable Synthesis of CuO Nanoparticles for Colorimetric Detection of Hydrogen Peroxide and Glucose

Fabrication of a novel MOF template-derived ZnCo2O4 composite for the non-enzymatic electrochemical detection of glucose

Glucose detection is one of the frequently occurring research due to increased cases of diabetes and the need for continuous monitoring of glucose. MOF template-derived nanocomposites have shown their potential in the field of sensors to address the shortcomings due to selectivity and sensitivity of the present-day sensors. A novel MOF template-derived ZnCo2O4 Composite (ZnCo2O4@MOF) sensing was designed and prepared in this study, and it was employed as an electrochemical sensor for the non-enzymatic detection of glucose with good selectivity and stability. The electrochemical characteristics of the present sensor were evaluated using a cyclic voltammetry (CV), differential pulse voltammetry (DPV), electrochemical impedance spectroscopy (EIS), and amperometry i-t. The template-mediated process and the synergism between the metallic components in the electrocatalyst have provided high electroactive surface area, electrolyte diffusion, and excellent stability that promote electron transfer and enhance the response current. With a wide linear range (0.1 − 100 μM), and 24.8 nM of low detection limit (S/N = 3). The constructed non-enzymatic biosensor exhibited long-term stability and remarkable reproducibility. Furthermore, the ZnCo2O4@MOF composite-modified electrode showed an excellent anti-interference ability against the common molecules that interfere during the detection of glucose.

Enhancing glucose detection: Vanadium-doped TiO2 (V0.07Ti0.93O2) as non-enzymatic biosensor

Enhancing glucose detection: Vanadium-doped TiO2 (V0.07Ti0.93O2) as non-enzymatic biosensor

Glucose Detection Based on Light Reflection in Modulated Optical Fibers for Continuous Diabetes Monitoring

<span lang="EN-US">Diabetes mellitus is a chronic disease characterized by elevated blood glucose levels. Approximately 463 million adults worldwide have diabetes, and nearly half of them remain undiagnosed. Early diagnosis and treatment of diabetes are crucial to prevent serious complications. Continuous glucose monitoring (CGM) offers numerous advantages over traditional fingertip blood glucose measurements. CGM allows patients to track their glucose levels in real time, identify patterns, and adjust their diet and medication appropriately. This research presents a novel optical fiber-based glucose sensor utilizing the macrobending modulation technique. This method offers several advantages, including ease of use, low cost, and strong signal generation. The sensor exploits the refractive index difference between the glucose solution and the optical fiber. Variations in glucose concentration induce changes in the refractive index, which are converted into voltage signals. The sensor exhibits a sensitivity of 337 mV/decade and demonstrates a linear relationship between the voltage signal and glucose concentration within the range of 0-10 mM. The macro bending-modulated optical fiber sensor shows potential as a simple, cost-effective, and efficient CGM tool. Further research is necessary to enhance the sensor's sensitivity and stability and to evaluate its performance in biological samples. </span>

Fe-doped Zinc-MOF composites and its test-strip employed for colorimetric detection of glucose in model and real urine samples

A new MOF {[Zn3(Cei)2(COO)2(Bimb)3].C2H2}n(Zinc-MOF) and its Iron doped composite (Fe@Zinc-MOF) based luminescent probe is fabricated which is corroborated with various analytical techniques and employed for Glucose detection in model and real urine samples. The linear correlation coefficient for 110 and 150 mg/dl Glucose are R2 = 0.97118 and 0.97118 respectively and the calculated result of KSV at low concentration is 3.2 × 104 M−1 and 3.8 × 104 M−1 in real urine sample. The minimum detection limit is 1.17 ppm and 0.846 ppm for 110 and 150 mg/dl Glucose correspondingly in real urine sample. Furthermore, the amalgamated strip is derived from filter paper and Fe@Zinc-MOF composite which is establishing an ultra-sensitive detection relationship with noticeable fluorescence changes with respect to different concentrations of Glucose.

Highly efficient MIM based SPR sensor for glucose detection using blueP/WS2 layers

In this article, a highly efficient surface plasmon resonance sensor for glucose detection in urine biosamples is presented. The proposed structure with the Ag-Si-Ag configuration was investigated and optimized using the transfer matrix method. In addition, blueP/WS2 and ZnO layers were implemented to further improve the sensitivity of the sensor by light-mater interaction enhancement in the sensing layer. The multilayer configuration of the optimized sensor consists of SiO2 prism /ZnO /Ag1/ Si/Ag2 /ZnO /blueP/WS2 layers, respectively and operates at λ = 633 nm. Different glucose concentrations of 0 to 15 mg dl−1 (for non-diabetic person), 0.625 gm dl−1, 1.25 gm/dL, 2.5 gm/dL, 5 gm/dL, and 10 gm dl−1 (for diabetic body), with refractive indices of 1.335, 1.336, 1.337, 1.338, 1.341, and 1.347, respectively have been regarded and the qualification parameters of S = 320 deg/RIU, FWHM = 1.5767 deg, FOM = 215.99 RIU−1, and minimum reflectance of 0.0318 have been evaluated. We believe that the proposed sensor could pave the way to easy and accurate detection of glucose concentration which is vital in control or treatment of diabetes.

Improvement of Hydrogen Peroxide and Glucose Detection in Serum using Persistent Luminescent Nanoparticles: Impact of Synthesis Parameters and Particle Size

AbstractPersistent Luminescent Nanoparticles (PLNPs) emit prolonged light after excitation, allowing getting images with high signal‐to‐noise ratio, making them particularly beneficial for in vitro biodetection. In this study, we report the preparation of a library of gallium and zinc‐based Persistent Luminescent Nanoparticles doped with chromium (ZnGa2O4:Cr3+) through two distinct syntheses conducted at 120 °C for 12 hours or 24 hours, followed by a calcination at 500 °C or 750 °C. Using centrifugation, and starting from polydisperse samples, we demonstrated the ability to achieve different sizes in a monodisperse manner. Furthermore, our research revealed that ZnGa2O4:Cr3+ (ZGO) nanoparticles react differently with hydrogen peroxide (H2O2) based on their size, synthesis duration, and calcination temperature. We observed the most significant amplification of persistent luminescence for ZGO particles prepared at 120 °C for 12 hours and calcinated at 500 °C, with a size of approximately 100 nm, in the presence of 100 mM H2O2 (later named ZGO‐2). This study enabled the detection of H2O2 in serum without autofluorescence using the developed PLNPs, with a detection limit of up to 2.1 μM and a recovery rate of around 99 %. Additionally, we designed a glucose test for based on the responsiveness of ZGO PLNPs to H2O2. Using glucose oxidase, the glucose detection limit in serum was established around 0.13 μM, with a detection range between 0–5 μM. These findings could open new avenues to further control the size, synthesis, calcination temperature, and persistent luminescence of PLNPs, thus enhancing their utility in the development of new in vitro biosensors.

Oxygen Vacancy-Induced Low-Valence reactive species enabling High-Efficient nonenzymatic glucose detection

NiCo2O4 (NCO), a typical spinel-type transition metal oxide, emerges as a promising candidate for non-electroenzymatic glucose sensors because of its stable structure and low overpotential. However, the practical applications of NCO are hindered by its limited intrinsic activity for glucose detection. Herein, we intentionally incorporated low-valence redox species into NCO nanowires by modulating the oxygen vacancies (VO-NCO NWs), thereby facilitating glucose oxidation reactivity. The concentration of low-valence species increases with the generated oxygen vacancies, which enriches the reactive redox species and enhances the intrinsic electrical conductivity, thereby improving the catalytic activity. Consequently, the optimized VO-NCO NWs exhibit highly efficient glucose detection with high sensitivity up to 19.65 mA·mM−1·cm−2, which is 4.6 times higher than that of the pristine NCO NWs, as well as a low limit of detection (LOD) of 0.15 μM. Furthermore, a flexible miniaturized three electrode (FMTE) assembled with optimized VO-NCO NWs provides a high sensitivity of 15.89 mA·mM−1·cm−2 and a low LOD of 0.18 μM in synthetic sweat. Under various bending conditions, the FMTE demonstrates good mechanical flexibility, with no discernible alterations in the response current. These findings provide a promising protocol for the dynamic monitoring of sweat composition to reveal human physiological health status.

Fabrication of porous copper oxide nanostructure on nickel foam electrode by a co-precipitation method for non-enzymatic glucose detection

A novel porous copper oxide nanostructure on nickel foam (CuO/NF) electrode has been successfully prepared through a co-precipitation way. The porous CuO structure and nickel foam can be integrated into a three-dimensional ordered and hierarchal CuO electrode sensor. The porous CuO structure contains many loosely packed nanoparticles and the nanochannels, which are beneficial for providing more active sites for electrocatalytic oxidation–reduction reactions. The Cu(III)/Cu(II) pair plays an essential role, which completes the charge transfer during the electrochemically catalyzed reaction. Two Cu(III) ions obtain two electrons from one molecule of glucose, which completes two electron transfers to produce one molecule of gluconic acid lactone. The results of the actual detection of Fetal Bovine Serum indicate that the CuO/NF electrode produced could be utilized for the determination of actual samples.

PH-sensitive fractal structured polyaniline in the honeycomb-patterned porous polymer film for the detection of dopamine and glucose

Using highly pH-sensitive fractal structured polyaniline (f-PANI) inducing conductivity change in the honeycomb-patterned (HCP) porous polymer film, we have applied for the detection of dopamine and glucose. Fractal-structured PANI in the HCP porous polymer film is formed by the same method recently reported using solid–liquid interfacial reaction. For the interfacial reaction, the HCP polystyrene (PS) porous film containing benzoyl peroxide (BPO) was immersed into the aniline aqueous solution under conditions of non-stirring for the growing of fractal structure instead of aggregated PANI. The pH sensitivity of the conductivity of the HCP film functionalized with fractal structured PANI was so high compared to the HCP film functionalized with simple aggregated PANI (a-PANI) under stirring conditions for the solid–liquid interfacial reaction. By using the high pH sensitive fractal structured PANI functionalized HCP film, dopamine, and glucose were selectively detected. The film acts as a micro reactor for the effective detection of dopamine and glucose.

The Fluorescent Detection of Glucose and Lactic Acid Based on Fluorescent Iron Nanoclusters.

In this paper, a novel fluorescent detection method for glucose and lactic acid was developed based on fluorescent iron nanoclusters (Fe NCs). The Fe NCs prepared using hemin as the main raw material exhibited excellent water solubility, bright red fluorescence, and super sensitive response to hydrogen peroxide (H2O2). This paper demonstrates that Fe NCs exhibit excellent peroxide-like activity, catalyzing H2O2 to produce hydroxyl radicals (•OH) that can quench the red fluorescence of Fe NCs. In this paper, a new type of glucose sensor was established by combining Fe NCs with glucose oxidase (GluOx). With the increase in glucose content, the fluorescence of Fe NCs decreases correspondingly, and the glucose content can be detected in the scope of 0-200 μmol·L-1 (μM). Similarly, the lactic acid sensor can also be established by combining Fe NCs with lactate oxidase (LacOx). With the increase in lactic acid concentration, the fluorescence of Fe NCs decreases correspondingly, and the lactic acid content can be detected in the range of 0-100 μM. Furthermore, Fe NCs were used in the preparation of gel test strip, which can be used to detect H2O2, glucose and lactic acid successfully by the changes of fluorescent intensity.

Glucose sensing performance of bimetallic MOFs CoFe-ZIF/CC for enzyme-free saliva sensor applications

Co-ZIF is widely believed as a promising material which shows potential in MOFs based enzyme-free sensors. However, the research of Co-ZIF in glucose sensor filed has been hampered, due to its poor electronic conductivity and slow ion diffusion caused by closed rhombohedral dodecahedron structure. In this work, the obtained Co0.95Fe0.05-ZIF presents highly opened nanosheet structure on CC, resulting in rich open active sites and ions moving channels. Compared with other reported ZIFs, the Co0.95Fe0.05-ZIF/CC exhibits excellent sensing performance with a high sensitivity of 3232.30 μA mM−1 cm−2 in the range of 0.20–1.00 mM and a low detection limit of less than 5 μM, due to its highly opened nanosheet structure. The Co0.95Fe0.05-ZIF/CC also shows excellent selectivity, repeatability and reproducibility for glucose detection. Furthermore, the variation trend of test results measured by this saliva sensor without any sample pre-treatment, is consistent with that of commercial blood glucose meter, indicating its potential in real applications. This synthesis strategy also provides a new direction of structure construction for high performance MOFs in enzyme-free glucose sensor field.

Polyaniline/titanium phosphate as a biosensor detection of glucose performance

In this study, we have prepared titanium phosphate (TiPO4) by photolysis-hydrothermal method, and then incorporated it with polyaniline (PANI) by oxidative polymerization method. FTIR, XRD and XPS confirmed the formation of nanocomposite. TGA analysis were also carried out for thermal stability characterization. The TiPO4/PANI nanocomposite has been employed as a biosensor for glucose disclosure via immobilization with glucose oxidase enzyme. Amperometry, cyclic voltammetry (CVs) and chemical impedance (EIS) were carried out for sensing of glucose. The linear range of glucose detection was noted from 20 to 100 μM by using amperometric analysis, and the LOD was found to be 5.44 μM.