Performance Of Glucose Biosensor Research Articles

An Enhanced Performance of Glucose Biosensor based on TiO2 Nanorod Arrays Decorated with Ag Nanoparticles

An Enhanced Performance of Glucose Biosensor based on TiO2 Nanorod Arrays Decorated with Ag Nanoparticles

Progress of Enzymatic and Non-Enzymatic Electrochemical Glucose Biosensor Based on Nanomaterial-Modified Electrode.

This review covers the progress of nanomaterial-modified electrodes for enzymatic and non-enzymatic glucose biosensors. Fundamental insights into glucose biosensor components and the crucial factors controlling the electrochemical performance of glucose biosensors are discussed in detail. The metal, metal oxide, and hybrid/composite nanomaterial fabrication strategies for the modification of electrodes, mechanism of detection, and significance of the nanomaterials toward the electrochemical performance of enzymatic and non-enzymatic glucose biosensors are compared and comprehensively reviewed. This review aims to provide readers with an overview and underlying concept of producing a reliable, stable, cost-effective, and excellent electrochemical performance of a glucose biosensor.

A glucose biosensor based on glucose oxidase fused to a carbohydrate binding module family 2 tag that specifically binds to the cellulose-modified electrode

The method of immobilization of glucose oxidase (GOD) on electrodes is especially important for the fabrication and performance of glucose biosensors. In this study, a carbohydrate binding module family 2 (CBM2) was successfully fused to the C terminal of GOD with a natural linker (NL) in endo-β-xylanase by genetic recombination, and a fusion GOD (GOD-NL-CBM2) was obtained. The CBM2 was used as an affinity adsorption tag for immobilization of the GOD-NL-CBM2 on a cellulose modified electrode. The specific activity of GOD-NL-CBM2 was comparable to that of the wild type GOD. In addition, the CBM2 tag of fusion GOD almost maintained its highest binding capacity under optimal catalytic conditions (pH 5.0, 50 °C). The morphology and composition analysis of the cellulose film reacted with and without GOD or GOD-NL-CBM2 confirmed the immobilization of GOD-NL-CBM2. The electrochemical properties of the GOD-NL-CBM2/cellulose film bioelectrode, with a characteristic peak of H2O2 at +0.6 V in the presence of glucose, revealed the capability of the immobilized GOD-NL-CBM2 to efficiently catalyze glucose and produce H2O2. Additionally, the current signal response of the biosensor to glucose was linear in the concentration range from 1.25 to 40 mM (r2 ≥ 0.99). The sensitivity and detection limit of the GOD-NL-CBM2/cellulose film bioelectrode were 466.7 μA mol−1 L cm-2 and 0.475 mM (S/N = 3), respectively. Moreover, the glucose biosensor exhibited a rapid current change (< 5 s), high reproducibility (Relative standard deviation, RSD < 5%), substrate selectivity and stability, and retained about 80 % of the original current response after 2 months. The affinity adsorption-based immobilization strategy for GOD provides a promising approach to develop a high performance glucose biosensor.

Orientated Immobilization of FAD-Dependent Glucose Dehydrogenase on Electrode by Carbohydrate-Binding Module Fusion for Efficient Glucose Assay.

The discovery or engineering of fungus-derived FAD-dependent glucose 1-dehydrogenase (FAD-GDH) is especially important in the fabrication and performance of glucose biosensors. In this study, a novel FAD-GDH gene, phylogenetically distantly with other FAD-GDHs from Aspergillus species, was identified. Additionally, the wild-type GDH enzyme, and its fusion enzyme (GDH-NL-CBM2) with a carbohydrate binding module family 2 (CBM2) tag attached by a natural linker (NL), were successfully heterogeneously expressed. In addition, while the GDH was randomly immobilized on the electrode by conventional methods, the GDH-NL-CBM2 was orientationally immobilized on the nanocellulose-modified electrode by the CBM2 affinity adsorption tag through a simple one-step approach. A comparison of the performance of the two electrodes demonstrated that both electrodes responded linearly to glucose in the range of 0.12 to 40.7 mM with a coefficient of determination R2 > 0.999, but the sensitivity of immobilized GDH-NL-CBM2 (2.1362 × 10−2 A/(M*cm2)) was about 1-fold higher than that of GDH (1.2067 × 10−2 A/(M*cm2)). Moreover, a lower detection limit (51 µM), better reproducibility (<5%) and stability, and shorter response time (≈18 s) and activation time were observed for the GDH-NL-CBM2-modified electrode. This facile and easy immobilization approach used in the preparation of a GDH biosensor may open up new avenues in the development of high-performance amperometric biosensors.

The effect of montmorillonite functionalization on the performance of glucose biosensors based on composite montmorillonite/PAN nanofibers

Herein, composite electrospun nanofibers (NFs) based on polyacrylonitrile (PAN) and smectite clay, montmorillonite (Mt) were employed as matrices for the development of amperometric glucose biosensors. Clays are established as suitable immobilization platforms for biocatalysts and allow functionalization through intercalation with organic molecules. The present study was focused on utilization of functional Mt in biosensing by incorporation in nanocomposite NFs and cross-linking of model enzyme, glucose oxidase (GOx).The initial clay mineral utilized was industrial type Mt (K10) and a comparison between simple PAN and composite nanofibers PAN/Mt K10 as biosensing matrices was performed. Further on, the study focused on modification of Mt with dioctadecyl dimethyl ammonium chloride (DDAC), an ammonium salt with extended alkyl chain and methylene blue (MB) as a redox mediator. The functionalization of Mt with each molecule was assessed by infrared spectroscopy (FTIR), correlated with the morphology of the nanocomposite NFs, visualized by scanning electron microscopy (SEM) and with the efficiency in amperometric glucose detection.Ultimately, both incorporation and functionalization of Mt improved the performance of the constructed biosensors, increasing the linearity, which extended up to 15 ˟ 10−3 M within two linear ranges (1.0 ˟ 10−5 - 2.45 ˟ 10−3 M and 2.45 ˟ 10−3 -15 ˟ 10−3 M) and improving the sensitivity up to 52 and 25 mAM−1cm−2, respectively. The detection limits were also lowered from 4.2 to 2.4 μM and the operational stability was enhanced up to 85% as a result of incorporation of DDAC-Mt.

The effect of adjusting the stroke value of jet dispenser on the performance of glucose biosensor with gold-plated electrode.

This study investigates the effect of dispensing glucose oxidase enzyme onto the reaction zone of a golden electrode via a jetting dispenser. Each droplet of enzyme solution dispensed onto the reaction zone of golden electrode weighs exactly the same at around 0.4 mg. This study shows that the spring and needle assembly can be controlled by adjusting the stroke value of the stroke adjustment knob to generate different jet dispensing effects, thus affecting the change of droplets of glucose oxidase enzyme solution within the reaction zone of the golden electrode. This study performs experiments using three stroke values, which are 0.8, 1.2, and 1.6 mm. The experimental results show that adjusting the stroke value to change the droplet of the dispensing liquid will significantly affect the accuracy of the test strip reading value. When the stroke value is adjusted to 1.5 mm, the standard deviation of the test strip is 3.8 mg/dL and the coefficient of variation is 4.1%-6.1%. The study suggested that adjusting the stroke value can stabilize the dispensed droplet to increase the stability of test strip reading, improving the accuracy of the test strip reading. This adjustment method can also be applied to the process of other biochemical sensors.

Effects of the gold nanoparticles including different thiol functional groups on the performances of glucose-oxidase-based glucose sensing devices

Thiol-based self-assembled anchor linked to glucose oxidase (GOx) and gold nanoparticle (GNP) cluster is suggested to enhance the performance of glucose biosensor. By the adoption of thiol-based anchors, the activity of biocatalyst consisting of GOx, GNP, polyethyleneimine (PEI) and carbon nanotube (CNT) is improved because they play a crucial role in preventing the leaching out of GOx. They also promote electron collection and transfer, and this is due to a strong hydrophobic interaction between the active site of GOx and the aromatic ring of anchor, while the effect is optimized with the use of thiophenol anchor due to its simple configuration. Based on that, it is quantified that by the adoption of thiophenol as anchor, the current density of flavin adenine dinucleotide (FAD) redox reaction increases about 42%, electron transfer rate constant (ks) is 9.1±0.1 s−1 and the value is 26% higher than that of catalyst that does not use the anchor structure.

Influence of LiClO4 Concentration on 1-D Polypyrrole Nanofibers for Enhanced Performance of Glucose Biosensor

In the present work, a template-free single-step fabrication of Lithium perchlorate (LiClO4) doped 1-D Polypyrrole nanofibers network (PNN) (without using electrospinning) toward glucose biosensing application has been reported. The PNN with different concentrations of LiClO4 was grown over the Platinum coated glass substrate by electropolymerization method and utilized as a support matrix for immobilization of enzyme. The effect of LiClO4 concentration on glucose biosensor performance has been demonstrated for the first time. The modification in morphology and reduction in charge transfer resistance of PNNs by varying LiClO4 concentration were found to play a significant role in the improved figure of merits of the biosensor. Among all the types of as-fabricated PNN electrodes (prepared by using different concentrations of LiClO4 viz. 1, 10, 50, and 70 mM) the best response was obtained corresponding to highest LiClO4 concentration. The enzyme loading and charge transfer resistance were drastically improved by approximately three folds owing to the higher surface area and improved conductivity of PNN electrodes thereby resulting in ten-fold increment in sensitivity. The as-prepared biosensor showed the highest sensitivity of 4.34 mA-cm−2-M−1 and a linear range of 0.1–4.6 mM with good stability and high selectivity for glucose detection.

Synthesis and characterization of microparticles based on poly-methacrylic acid with glucose oxidase for biosensor applications

In the line of the applicability of biocompatible monomers pH and temperature dependent, we assayed poly-methacrylic acid (p-MAA) microparticles as immobilization system in the design of enzymatic biosensors. Glucose oxidase was used as enzyme model for the study of microparticles as immobilization matrices and as biological material in the performance of glucose biosensors. The enzyme immobilization method was optimized by investigating the influence of monomer concentration and cross-linker content (N′,N′-methylenebisacrylamide), used in the preparation of the microparticles in the response of the biosensors. The kinetics of the polymerization and the effects of the temperature were studied, also the conversion of the polymerization was determinates by a weight method. The structure of the obtained p-MAA microparticles were studied through scanning electron microscopy (SEM) and differential scanning microscopy (DSC). The particle size measurements were performed with a Galai-Cis 1 particle analyzer system. Furthermore, the influence of the swelling behavior of hydrogel matrix as a function of pH and temperature were studied. Analytical properties such as sensitivity, linear range, response time and detection limit were studied for the glucose biosensors. The sensitivity for glucose detection obtained with poly-methacrylic acid (p-MAA) microparticles was 11.98mAM−1cm−2 and 10μM of detection limit. A Nafion® layer was used to eliminate common interferents of the human serum such as uric and ascorbic acids. The biosensors were used to determine glucose in human serum samples with satisfactory results. When stored in a frozen phosphate buffer solution (pH 6.0) at −4°C, the useful lifetime of all biosensors was at least 550 days.

Evaluation of Immobilization Techniques for the Fabrication of Nanomaterial-Based Amperometric Glucose Biosensors

Eleven glucose biosensors were prepared by cross-linking, entrapment, and layer-by-layer assembly to investigate the influence of these immobilization methods on performance. The effects of separate nanozeolites combined with magnetic nanoparticles and multiwalled carbon nanotubes in the enzyme composition on the performance of glucose biosensors were compared. Cyclic voltammetric studies were carried out on the biosensors. Acrylonitrile copolymer/nanozeolite/carbon nanotube and acrylonitrile copolymer/nanozeolite/magnetic nanoparticle electrodes prepared by a cross-linking method showed the highest electroactivity. These results indicated that a synergistic effect occurred when multiwalled carbon nanotubes, magnetic nanoparticles, and nanozeolites were combined that greatly improved the electron transfer ability of the sensors. Amperometric measurements by the glucose oxidase electrodes were obtained that showed that the acrylonitrile copolymer/nanozeolite/carbon nanotube electrode was the most sensitive (10.959 microamperes per millimolar). The lowest detection limit for this biosensor was 0.02 millimolar glucose, with a linear dynamic range up to 3 millimolar. The response after thirty days was 81 percent of the initial current.

Preparation of gold nanowires and its application in glucose biosensing

In this paper, well-ordered gold nanowires were synthesized by utilizing anodic aluminium oxide (AAO) templates in combination with direct electrodeposition. The morphology and structure of AAO template and gold nanowires were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM) and X-ray diffraction, respectively. Glucose biosensors were fabricated by chemical cross linking method with glutaraldehyde in the absence and presence of gold nanowires. Cyclic voltammogram and amperometric mode were used to measure the performance of glucose biosensors. Lower detection limit of 5μM and wide linear range between 20μM and 2mM with fast response were achieved by glucose biosensor in the presence of gold nanowires.

Highly enhanced performance of glucose biosensor via in situ growth of oriented Au micro-cypress

High sensitivity and accuracy are strongly required for biosensors due to their special application in the life and health of humans. In order to greatly enhance the above two parameters of the prepared biosensor, the architectures of Prussian blue and Au were purposefully designed. A single layer of PB grid with tight nano-holes was constructed to serve as a mould for the constraint of further Au deposition. Based on the steric hindrance effect, the Au crystal can be pushed towards one direction to in situ form a shape of a micro-cypress. Under a very low operation potential, −0.05 V, this composite film has been confirmed to own excellent abilities of performance enhancement and anti-interference as a glucose biosensor. This synthesis strategy can be expected to provide inspiration for morphology control of materials and high performance development of biosensors.

Thermally stable improved first-generation glucose biosensors based on Nafion/glucose-oxidase modified heated electrodes

We illustrate how the use of heated electrodes enhances the performance of glucose biosensors based on amperometric detection of the glucose-oxidase generated hydrogen peroxide. Nafion is shown to be an excellent matrix to protect glucose-oxidase from thermal inactivation during the heating pulses. The influence of the electrode temperature upon the amperometric response is examined. Temperature pulse amperometry (TPA) has been used to obtain convenient peak-shaped analytical signals. Surprisingly, up to 67.5 °C, the activity of Nafion-entrapped glucose-oxidase is greatly enhanced (24-fold) by accelerated kinetics rather than decreased by thermal inactivation. Amperometric signals even at elevated temperatures are stable upon prolonged operation involving repetitive measurements. The linear calibration range is significantly extended.

Studies on the electrochemical performance of glucose biosensor based on ferrocene encapsulated ORMOSIL and glucose oxidase modified graphite paste electrode

The electrochemical performance of a new glucose biosensor is reported. The glucose biosensor is developed using glucose oxidase (GOD) and ferrocene encapsulated palladium (Pd)-linked organically modified sol–gel glass (ORMOSIL) material incorporated within graphite paste electrode. The ORMOSIL material incorporated within graphite paste electrode behaves as an excellent electrocatalyst for the oxidation of enzymatically reduced GOD. The electrochemical behavior of new glucose biosensor has been examined by cyclic volammetry and amperometric measurements. The bioelectrocatalysis of ORMOSIL embedded within graphite paste as a function of storage time and varying concentration of ORMOSIL is reported. The initial amperometric response on glucose sensing is recorded to be 145 μA at 15% (w/w) concentration of the ORMOSIL which is decreased to 20 μA at 5% of the same keeping GOD concentration constant. The variation of electrochemical behavior of the ORMOSIL embedded within graphite paste as a function of time has also been studied based on cyclic voltammetry. The voltammograms showing the reversible electrochemistry of ORMOSIL encapsulated ferrocene is changed into a plateau shape as a function of time, however, the electrocatalytic behavior is still retained. The practical usability of new glucose sensor has been compared with earlier developed glucose sensor. The sensitivity, response time and linearity of the new glucose biosensor are found to be excellent over earlier reported glucose biosensor. The amperometric response, calibration curve and practical applications of new glucose sensor are reported.

Performance of glucose biosensor based on oxygen electrode in physiological fluids and at body temperature

A potentially implantable glucose biosensor for continuous monitoring of glucose levels in diabetic patients has been developed. The glucose biosensor is based on an amperometric oxygen electrode and glucose oxidase immobilized on carbon powder held in the form of a liquid suspension. The enzyme material can be replaced (the sensor recharged) without sensor disassembly. Diffusion membranes made of silastic coatings over a microporous polycarbonate membrane are used. Calibration curves of the sensors in phosphate buffer solution and in undiluted blood plasma at body temperature have been obtained. The reproducibility of the sensor response in serum at body temperature is demonstrated. The sensors have a stable signal during storage and continuous operation at body temperature for a period of at least one month.