Detection Of Glucose In Urine Research Articles

Bimetal Thin Film, Semiconductors, and 2D Nanomaterials in SPR Biosensors: An Approach to Enhanced Urine Glucose Sensing.

This work introduces a systematic approach for the development of Kretschmann configuration-based biosensors designed for non-invasive urine glucose detection. The methodology encompasses the utilization of various semiconductors, including Silicon (Si), Germanium (Ge), Gallium Nitride (GaN), Aluminum Nitride (AlN), and Indium Nitride (InN), in combination with a bimetallic layer (comprising Au and Ag films of equal thickness) to enhance the biosensor sensitivity. Additionally, 2D nanomaterials, such as Black Phosphorus and Graphene, are integrated into the semiconductor layers to enhance performance further. These configurations are meticulously optimized through the application of the transfer matrix method (TMM), and the sensing parameters are assessed using the angular modulation method. Among the semiconductors, AlN and GaN exhibit superior results. On these substrates, Graphene and Black phosphorous (BP) layers are applied, resulting in four final structures (thicknesses in nm): BK7/Au(26)/Ag(26)/Si(6)/BP(0.53)/Biosample, BK7/Au(26)/Ag(26)/AlN(14)/BP(0.53)/Biosample, BK7/Au(26)/Ag(26)/GaN(12)/BP(0.53)/Biosample, and BK7/Au(26)/Ag(26)/GaN(12)/Graphene(0.34)/Biosample. These biosensors achieve Sensitivity(° /RIU) and Figure of Merit (FoM) (1/RIU) of 380, 360, 440, 400, and 58.5, 90, 90.65, and 82.4, respectively. Subsequently, these high-performing sensors undergo testing with actual urine glucose samples. Among them, two biosensors, BK7/Au(26)/Ag(26)/AlN(14)/BP (0.53)/Biosample and BK7/Au(26)/Ag(26)/GaN(14)/Graphene(0.34)/Biosample, exhibit outstanding performance, with sensitivities (° /RIU) and FoM (1/RIU) of 394.44 & 294.44, and 112.6 & 92.01 respectively. A comparison is also made with relevant previously published work, revealing improved performance in glucose detection.

Cotton threads encapsulated by thermal contraction tube for point-of-care diagnostics

Passive microfluidic devices based on capillary force are popular choices for point-of-care diagnostics. Paper, threads and cloth have been used to fabricate these microfluidic devices. Here, we introduced a novel method for packaging microfluidic thread-based analytical devices (μTADs) by encapsulating cotton threads in thermal contraction tubes. This package method can help to increase convenience during practice. At first, we investigate the influence of this package method on the capillary flow behavior and water absorption capacity of cotton threads. Then, we show the possibility of this package method in preparing μTADs with complex shapes. Lastly, we successfully use μTADs based on this package method for applications in point-of-care diagnostics including glucose detection in urine, fibrinogen detection in blood plasma, and plasma separation from whole blood samples and hematocrit (HCT) measurement. The package method is promising in expanding the applications of μTADs in point-of-care diagnostics.

Enhancing urine glucose sensing performance through the introduction of two dimensional-transition metal dichalcogenides and gold nanoparticles into silver/UiO-66 chip of surface plasmon resonance

This work presents a high-performance surface plasmon resonance (SPR)-based biosensor for glucose detection. While adding a metal–organic framework layer, UiO-66, to the biosensor improves selectivity and enables direct detection without additional receptors, it does not significantly enhance sensitivity. A SPR-based biosensor is proposed to overcome this limitation by introducing a layer of 2D-transition metal dichalcogenides (2D-TMD) and decorating the UiO-66 structure with gold nanoparticles (UiO-66AuNP). The optical properties of the biosensor for glucose detection in urine are investigated by employing the finite difference time domain (FDTD) method with Kretschmann configuration at a wavelength of 633 nm, and its performance is effectively improved by incorporating 2D-TMD and AuNP layers into the biosensor structure. Notably, the SPR-based biosensor with the decorated UiO-66 layer exhibits a further change in the SPR angle in the presence of glucose-containing urine. Using computational studies, various performance parameters, such as the biosensors’ signal-to-noise ratio and quality factor, are evaluated in addition to sensitivity. The maximum sensitivity achieved is 309.3°/RIU for the BK7/Ag/PtSe2/WSe2/MoS2/UiO-66AuNP/sensing medium structure. The exceptional performance of the proposed biosensor structure demonstrates its suitability for precise glucose detection in urine while also opening new avenues for developing bioreceptor-free SPR-based sensors.

Paper-based ratiometric fluorescent sensing platform based on mixed quantum dots for the detection of glucose in urine.

A paper-based ratiometric fluorescent sensing platform has been developed for glucose detection based on a dual-emission fluorescent probe consisting of carbon quantum dots (C QDs) and CdTe QDs. When the two kinds of QDs are mixed, the fluorescence of C QDs is reversibly quenched by CdTe QDs. However, in the presence of glucose, the fluorescence of CdTe QDs is quenched by H2O2 catalyzed by glucose oxidase (GOx), which restores the fluorescence of C QDs. The proposed paper-based ratiometric fluorescent sensing platform exhibited good sensitivity and selectivity towards glucose. The working linear range was 0.1 mM to 50 mM with a limit of detection (LOD) of 0.026 mM. Additionally, the proposed paper-based sensor possesses viability for the determination of glucose in actual urine samples.

Ag@AuNP-Functionalized Capillary-Based SERS Sensing Platform for Interference-Free Detection of Glucose in Urine Using SERS Tags with Built-In Nitrile Signal.

A Ag@AuNP-functionalized capillary-based surface-enhanced Raman scattering (SERS) sensing platform for the interference-free detection of glucose using SERS tags with a built-in nitrile signal has been proposed in this work. Capillary-based SERS capture substrates were prepared by connecting 4-mercaptophenylboronic acid (MBA) to the surface of the Ag@AuNP layer anchored on the inner wall of the capillaries. The SERS tags with a built-in interference-free signal could then be fixed onto the Ag@AuNP layer of the capillary-based capture substrate based on the distinguished feature of glucose, which can form a bidentate glucose-boronic complex. Thus, many "hot spots" were formed, which produced an improved SERS signal. The quantitative analysis of glucose levels was realized using the interference-free SERS intensity of nitrile at 2222 cm-1, with a detection limit of about 0.059 mM. Additionally, the capillary-based disposable SERS sensing platform was successfully employed to detect glucose in artificial urine, and the new strategy has great potential to be further applied in the diagnosis and control of diabetes.

Corrigendum: Effect of 2-D nanomaterials on sensitivity of plasmonic biosensor for efficient urine glucose detection

Corrigendum: Effect of 2-D nanomaterials on sensitivity of plasmonic biosensor for efficient urine glucose detection

Highly Sensitive Bimetallic-Metal Nitride SPR Biosensor for Urine Glucose Detection.

The present study introduces a highly sensitive bimetallic SPR biosensor based on metal nitride for efficient urine glucose detection. Using a BK-7 prism, Au (25 nm), Ag (25nm), AlN (15 nm), and a biosample (urine) layer, the proposed sensor comprises of five layers. The selection of the sequence and dimensions of both metal layers is based on their performance in a number of case studies including both monometallic and bimetallic layers. After optimizing the bimetallic layer as Au (25 nm) - Ag (25 nm), various nitride layers were used to further increase the sensitivity by utilizing the synergistic effect of the bimetallic and metal nitride layers through case studies of several urine samples, ranging from nondiabetic to severely diabetic patients. AlN is determined to be the best suited material, and its thickness is optimized to 15 nanometers. The performance of the structure has been evaluated using a visible wavelength, i.e., λ = 633 nm, in order to increase sensitivity while providing room for low-cost prototyping. With the layer parameters optimized, a significant sensitivity of 411°/RIU (Refractive Index Unit) and figure of merit (FoM) of 105.38 /RIU has been achieved. The computed resolution of the proposed sensor is 4.17e-06. This study's findings have also been compared to some recently reported results. The proposed structure would be useful for detecting glucose concentrations, with a rapid response as measured by a substantial shift in resonance angle in SPR curves.

Tablet-Based Sensor: A Stable and User-Friendly Tool for Point-of-Care Detection of Glucose in Urine.

The colorimetric detection of glucose in urine through enzymatic reactions offers a low-cost and non-invasive method to aid in diabetes management. Nonetheless, the vulnerability of enzymes to environmental conditions, particularly elevated temperatures, and their activity loss pose significant challenges for transportation and storage. In this work, we developed a stable and portable tablet sensor as a user-friendly platform for glucose monitoring. This innovative device encapsulates glucose oxidase and horseradish peroxidase enzymes with dextran, transforming them into solid tablets and ensuring enhanced stability and practicality. The enzymatic tablet-based sensor detected glucose in urine samples within 5 min, using 3,3',5,5'-tetramethylbenzidine (TMB) as the indicator. The tablet sensor exhibited responsive performance within the clinically relevant range of 0-6 mM glucose, with a limit of detection of 0.013 mM. Furthermore, the tablets detected glucose in spiked real human urine samples, without pre-processing, with high precision. Additionally, with regard to thermal stability, the enzyme tablets better maintained their activity at an elevated temperature as high as 60 °C compared to the solution-phase enzymes, demonstrating the enhanced stability of the enzymes under harsh conditions. The availability of these stable and portable tablet sensors will greatly ease the transportation and application of glucose sensors, enhancing the accessibility of glucose monitoring, particularly in resource-limited settings.

Dipstick Sensor Based on Molecularly Imprinted Polymer‐Coated Screen‐Printed Electrodes for the Single‐Shot Detection of Glucose in Urine Samples—From Fundamental Study toward Point‐of‐Care Application

AbstractGlucose biosensors play an extremely important role in health care systems worldwide. Therefore, the field continues to attract significant attention leading to the development of innovative technologies. Due to their characteristics, Molecularly Imprinted Polymers (MIPs) represent a promising alternative to commercial enzymatic sensors. In this work, a low‐cost, flexible MIP‐based platform for glucose sensing by integrating MIP particles directly into screen‐printed electrodes (SPEs) is realized. The sensor design allows the detection of glucose via two different transducer principles, the so‐called “heat‐transfer method” (HTM) and electrochemical impedance spectroscopy (EIS). The sensitivity and selectivity of the sensor are demonstrated by comparing the responses obtained toward three different saccharides. Furthermore, the application potential of the MIP‐SPE sensor is demonstrated by analyzing the response in urine samples, showing a linear range of 14.38–330 µm with HTM and 1.37–330 µm with EIS. To bring the sensor closer to a real life application, a handheld dipstick sensor is developed, allowing the single‐shot detection of glucose in urine using EIS. This study illustrates that the simplicity of the dipstick readout coupled with the straightforward manufacturing process opens up the possibility for mass production, making this platform a very attractive alternative to commercial glucose sensors.

Artificial intelligence-assisted colorimetry for urine glucose detection towards enhanced sensitivity, accuracy, resolution, and anti-illuminating capability

Artificial intelligence-assisted colorimetry for urine glucose detection towards enhanced sensitivity, accuracy, resolution, and anti-illuminating capability

Effect of 2-D nanomaterials on sensitivity of plasmonic biosensor for efficient urine glucose detection

This paper presents a multi-layered Kretschmann configuration-based Surface Plasmon Resonance (SPR) biosensor for the detection of urine glucose. The modelling, simulation, and analysis have been done by using Silver (Ag) and Gold (Au) layer on the low refractive index prism BK-7 separately, which created two structures: structure-I (BK7/Ag/Bio-sample) and structure-II (BK7/Au/Bio-sample). Urine samples from a non-diabetic person (0–15 mg/dL) and a diabetic person (.625 gm/dL, 1.25 gm/dL, 2.5 gm/dL, 5 gm/dL, and 10 gm/dL) with the corresponding refractive indices of 1.335, 1.336, 1.337, 1.338, 1.341, and 1.347, respectively, have been used as a bio-sample that has been put on the top layer of the sensor. An investigation was conducted to improve the performance parameters of the proposed plasmonic biosensor by layering different 2-D nanomaterials (graphene, BP) and TMDC materials (MoS2, MoSe2, WS2, and WSe2) over the silicon (Si) layer in both structures at a visible wavelength of 633 nm, using Transfer Matrix Method (TMM). With layer thickness optimization, Structure-I (BK7/Ag (56 nm/Si (3 nm)/WS2 (.8 nm)/Bio-sample) shows a sensitivity of 200 °/RIU which is enhanced up to 1.7 times that of the conventional biosensor (BK7/Ag/Bio-sample) and 1.3 times that of the BK7/Ag (56 nm)/Si (3 nm)/Bio-sample based biosensor. Whereas in Structure-II (BK7/Au (50 nm)/Si (3 nm)/BP (.53 nm)/Bio-sample) with optimised layer thickness, we obtained a sensitivity of 273.4°/RIU, which is enhanced up to 2.2 times that of the conventional biosensor (BK7/Au/Bio-sample) and 1.3 times that of the BK7/Au (50 nm)/Si (3 nm)/Bio-sample. Other performance parameters such as detection accuracy for Structure-I and Structure-II are .5617 degree−1 and .134 degree−1 respectively. The Figure of merit for Structure-I and Structure-II are 112.35/RIU and 36.89/RIU respectively. Therefore, we expect Structure-I (BK7/Ag (56 nm/Si (3 nm)/WS2 (.8 nm)/Bio-sample) and Structure-II (BK7/Au (50 nm)/Si (3 nm)/BP (.53 nm)/Bio-sample) have the potential to detect the glucose concentration with quick response and high sensitivity in terms of the resonance angle shift in SPR curves.

The chemistry of the Baeyer and Hoppe-Seyler test for glucose in urine

Glucose is an analyte and has drawn the attention of researchers for a long time. Baeyer accomplished several synthesis for indigo. The one under study was adapted by Hoppe-Seyler for detection of glucose in urine. The blue colour observed in the test is due to the formation of indigo. The reagent used in the test is o-nitrophenylpropiolic acid. However the route from the starting compound to indoxyl has not been cleared out. There are missing intermediates or inadequate ones have been proposed. In this communication we provide the route and the reaction mechanism involved in each step. This is in accordance with experimental data and the chemical deportment of the involved compounds.

A multi-calibration potentiometric sensing array based on diboronic acid-PtAu/CNTs nanozyme for home monitoring of urine glucose

All-solid-state potentiometric sensors that are easily miniaturized and arrayed are widely used in home diagnostics. However, changes in sample matrix compositions tend to affect the basic potential of the potentiometric sensor, and pH of sample could change the response slope, thus affecting the detection reliability. This study takes the detection of glucose in urine as a model to increase the reliability of potentiometric sensors in home detection. PtAu/CNTs nanozyme modified by diboronic acid has been designed, showing better catalytic selectivity for glucose by experiments and theoretical calculations. Moreover, glucose electrode group in a multi-calibration glucose potentiometric sensing array can realize the basic potential calibration of sensing channel by the calibration channel. Meanwhile, the pH electrode group can not only measure the urine pH, but also calibrate the response slope of the glucose electrode group, thus improving the reliability of home detection.

Microbe-Based Sensor for Long-Term Detection of Urine Glucose.

The development of a reusable and low-cost urine glucose sensor can benefit the screening and control of diabetes mellitus. This study focused on the feasibility of employing microbial fuel cells (MFC) as a selective glucose sensor for continuous monitoring of glucose levels in human urine. Using MFC technology, a novel cylinder sensor (CS) was developed. It had a quick response time (100 s), a large detection range (0.3–5 mM), and excellent accuracy. More importantly, the CS could last for up to 5 months. The selectivity of the CS was validated by both synthetic and actual diabetes-negative urine samples. It was found that the CS’s selectivity could be significantly enhanced by adjusting the concentration of the culture’s organic matter. The CS results were comparable to those of a commercial glucose meter (recovery ranged from 93.6% to 127.9%) when the diabetes-positive urine samples were tested. Due to the multiple advantages of high stability, low cost, and high sensitivity over urine test strips, the CS provides a novel and reliable approach for continuous monitoring of urine glucose, which will benefit diabetes assessment and control.

Nanomaterial-based optical- and electrochemical-biosensors for urine glucose detection: A comprehensive review

Urine glucose detection is an important diagnostic tool for screening and early diagnosis of diabetes mellitus. Detection of urine glucose has many advantages over blood glucose, such as non-invasive, easy-to-detect, simple sampling and being well accepted by patients. Therefore, it is commonly used to monitor diabetes progression, assist in therapeutic intervention as well as in point-of-care testing (POCT). In recent years, with the development of material science, electrochemistry and miniaturization technology, novel applications of natural enzymes, nanozymes as well as nanomaterials, such as metal (Au, Pt, Ni, Co, etc.), alloy, grapheme, in the analysis of urine glucose level have been increasing sharply. In particular, different types of nanozymes-based biosensors, inspired by natural enzymes, have been developed with improved characteristics of being low-cost, stable, and mass-produced. On the other hand, making use of portable devices, such as smartphones and microfluidic paper-based analytical devices, has facilitated on site accurate urine glucose monitoring in real time. All these rapid advancements in nanotechnologies and devices have contributed greatly to the development of cost effective, highly sensitive, user friendly urine glucose biosensors. This review summarizes the most recent improvements in two major types of urine glucose biosensors: the optical- and electrochemical-biosensors. We also discuss the limitations, challenges and perspectives of these biosensors. Finally, we propose future research directions, development trends and potential clinical applications of nanomaterial-based biosensors developed for urine glucose detection.

Artificial Intelligence-Assisted Colorimetry for Urine Glucose Detection Towards Enhanced Sensitivity, Accuracy, Resolution and Anti-Illuminating Capability

Artificial Intelligence-Assisted Colorimetry for Urine Glucose Detection Towards Enhanced Sensitivity, Accuracy, Resolution and Anti-Illuminating Capability

Highly sensitive urine glucose detection with graphene field-effect transistors functionalized with electropolymerized nanofilms

Graphene field-effect transistors are able to successfully monitor glucose in urine samples, showing their potential towards the fabrication of point-of-care glucose testing devices.

Sensitivity enhancement of a plasmonic biosensor for urine glucose detection by employing black phosphorous

A novel, to the best of our knowledge, optimized structure is proposed to enhance the sensitivity of a surface plasmon resonance (SPR)-based biosensor for urine glucose detection by adding a few layers of black phosphorous (BP) (two-dimensional material) over the zinc oxide (ZnO) sandwiched in between gold (Au) and silver (Ag) bimetallic layers. Results show that with an optimized thickness of 42 nm/Au, 12 nm/ZnO, .05 nm/Ag, and 2.65 nm/BP, the sensitivity of 289°/RIU can be achieved at a 633 nm operating wavelength. This is enhanced up to 1.5 times from the conventional biosensor. It is further enhanced up to 3 times with the addition of five numbers of BP sheet layers (each sheet has a thickness of 0.53 nm) over the Au/ZnO/Ag layers, as BP possesses a high absorption coefficient at the incident wavelength of 633 nm. This biosensor is rather efficient at responding to the minute change of 0.001 in the refractive index of urine samples for non-diabetic persons (0–15 mg/dL) and diabetic persons (0.625 gm/dL, 1.25 gm/dL, 2.5 gm/dL, 5 gm/dL, and 10 gm/dL) with the corresponding refractive indices of 1.335, 1.336, 1.337, 1.338, 1.341, and 1.347. It provides significant resonance shift and higher sensitivity in terms of changes in the resonance angle shift. This proposed work has the potential to detect glucose concentration levels with higher accuracy and with faster sensor responses.

Thermal Detection of Glucose in Urine Using a Molecularly Imprinted Polymer as a Recognition Element.

Glucose bio-sensing technologies have received increasing attention in the last few decades, primarily due to the fundamental role that glucose metabolism plays in diseases (e.g., diabetes). Molecularly imprinted polymers (MIPs) could offer an alternative means of analysis to a field that is traditionally dominated by enzyme-based devices, posing superior chemical stability, cost-effectiveness, and ease of fabrication. Their integration into sensing devices as recognition elements has been extensively studied with different readout methods such as quartz-crystal microbalance or impedance spectroscopy. In this work, a dummy imprinting approach is introduced, describing the synthesis and optimization of a MIP toward the sensing of glucose. Integration of this polymer into a thermally conductive receptor layer was achieved by micro-contact deposition. In essence, the MIP particles are pressed into a polyvinyl chloride adhesive layer using a polydimethylsiloxane stamp. The prepared layer is then evaluated with the so-called heat-transfer method, allowing the determination of the specificity and the sensitivity of the receptor layer. Furthermore, the selectivity was assessed by analyzing the thermal response after infusion with increasing concentrations of different saccharide analogues in phosphate-buffered saline (PBS). The obtained results show a linear range of the sensor of 0.0194–0.3300 mM for the detection of glucose in PBS. Finally, a potential application of the sensor was demonstrated by exposing the receptor layer to increasing concentrations of glucose in human urine samples, demonstrating a linear range of 0.0444–0.3300 mM. The results obtained in this paper highlight the applicability of the sensor both in terms of non-invasive glucose monitoring and for the analysis of food samples.

An Electrochemical Nonenzymatic Microsensor Modified by Nickel Cobaltate Nanospheres for Glucose Sensing in Urine

Diabetes is a common chronic disease, so it is particularly important to develop a convenient, fast, and highly sensitive non-enzymatic glucose sensor. In this work, a high sensitivity, low cost sensor was prepared on the substrate of printed circuit board. The nickel cobaltate (NiCo <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> ) spherical nanomaterials were synthesized by facile hydrothermal and calcining methods. The working electrode was modified by NiCo <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> nanospheres and the cation exchange resin in turn. Nafion cation exchange film can help to reduce the interference caused by surface-active compounds cyclic voltammetry- amperometric method was used to study the electrocatalytic performance of the sensor at room temperature. The sensor modified by NiCo <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> nanospheres showed good sensor performance for glucose, including excellent sensitivity (3449.14 μA mM <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1 </sup> cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> ), wide linear range ( 1 μM to 100 mM), and low detection limit ( 0.376 μM). In addition, it has high selectivity, repeatability and stability. The sensor proposed in this work has been successfully applied to the detection of glucose in urine, and the results are consistent with the actual glucose concentration in urine.