KR100765438B1 - Functional nanofibrous membrane based glucose biosensor and method for producing the same - Google Patents

Abstract

A functional nanofibrous membrane-based glucose biosensor and a method for producing the same biosensor are provided to eliminate use of enzyme and improve glucose-detection sensitivity and selectivity by increasing surface area produced through an electrospinning method. A functional nanofibrous membrane is produced by electrospinning a mixture containing poly(vinylidene fluoride) and poly(aminophenyl boronic acid) in a weight ratio of 95-99 : 5-1. A sensor electrode is produced by depositing the nanofibrous membrane on an ITO(indium tin oxide) plate. A glucose biosensor contains the sensor electrode using the functional nanofibrous membrane.

Description

Functional Nanofibrous Membrane Based Glucose Biosensor And Method for Producing the Same}

1 is a diagram showing a microstructure characteristic that provides a manufacturing process of PVdF / PAPBA-NFM electrode and a characteristic of sensing glucose by electrospinning.

2 is a photograph showing a FESEM image of PVdF / PAPBA-NFM.

3 is a graph showing the FT-IR spectra of electrospun PVdF / PAPBA-NFM (a) and PVdF (b).

4 shows a cyclic voltammogram plot of PVdF / PAPBA-NFM in 1M HCl at 50 mV / s scan rate.

FIG. 5 is a graph showing the amperometric response of PVdF / PAPBA-NFM with continuous addition of 1 mM glucose (electrolyte: phosphate buffer (pH = 7.5), voltage: 0.4 V), and the inserted figure shows glucose with current Figure shows the calibration of the concentration (1-15 mM).

6 is a graph showing the amperometric response of PVdF / PAPBA-NFM to glocose (a), uric acid (b), ascorbic acid (c) and acetoaminophene (d) (voltage: 0.4V, electrolyte: phosphate buffer) (pH = 7.5)

7 is a graph showing flow injection amperometric response of PVdF / PAPBA-NFM to increasing concentrations of (1-16 mM) glucose solution (operating voltage: 0.4 V, flow rate: 1.0 mL / min).

FIG. 8 is a graph showing the stability to storage of PVdF / PAPBA-NFM relative to glocose stored in phosphate buffer (pH = 7.5).

The present invention relates to a nanofiber membrane and a biosensor using the same. More specifically, the present invention relates to enzyme-free glucose sensors, comprising poly (vinlylidene fluoride), PVdF and poly (aminophenylboronic acid) And nanofiber membranes prepared from composites comprising PAPBA) and their application to sensors.

The present invention also relates to a method for producing a functional nanofiber membrane comprising electrospinning a composite comprising PVdF and PAPBA and a method for producing an electrode for a biosensor comprising collecting it on a plate.

Active research on the development of biosensors through current measurement has been continued. Glucose is a broad source of nutrition for most organisms and plays a fundamental role in energy supply, carbon storage, biosynthesis and carbon skeleton and cell wall formation. The development of glucose sensors through current measurement has been extensively studied for their importance in the treatment of diabetes (Taylor, 1999).

Most recent studies on glucose sensors have shown that glucose oxidase (Yu et al., 2003) or glucose dehydrogenase (Yamazaki et al.) Promotes the oxidation of glucose to gluconolactone. , 2000). The electrode surface to which the enzyme is immobilized is prepared to transfer electrons quickly and directly (Cu et al., 2001).

In addition, in most cases enzyme-based sensors require oxidase mediators (Forrow and Walters, 2004) to improve sensor sensitivity and selectivity. However, amperometric enzyme electrodes have some inherent problems, such as relatively low output current concentrations and gradual degradation of enzyme activity. In addition, the stability and toxicity of certain mediators limit their application in vivo . In addition, sensors based on enzyme immobilization are susceptible to denaturation. In other words, hydrogen peroxide produced as a by-product of the enzyme reaction caused enzyme degeneration.

There have been many attempts to develop enzyme-free glucose sensors. In one embodiment, glucose is platinum (Bae et al., 1991), gold (Adzic et al., 1989), copper (Yeo et al., 2000) and nickel (Yeo). et al., 2001) and electron-catalytic oxidation on metal surfaces.

However, metal electrodes quickly lose their activity by accumulation of chemisorbed intermediates that interfere with the electrocatalyst surface. Another disadvantage of these metal electrodes is their lack of selectivity for glucose, an essential requirement for sensors. Various organic materials are oxidized simultaneously with glucose on these electrode surfaces to indirect electrochemical signals.

Therefore, it is important to manufacture a robust and enzyme free glucose sensor. Boronic acid interacts with cyanide (Badugu et al., 2004), fluoride (Cesare and Lakowicz, 2002) and di-ols (Deore and Freund, 2003). It is known to work and has been used for sensor development. Today, much research is being reported on enzyme-free sensors based on boric acid. Fluorescence (Wang et al., 2005, Badugu et al., 2005), UV-Vis (Shinmori et al., 1995), near-IR (Pringsheim et al., 1999), surface plasmon resonance spectroscopy plasmon resonance spectroscopy (Gabai et al., 2001 and Lee et al., 2002), potentiometry (Shoji and Freund, 2001, Shoji and Freund, 2002) and quartz crystal microbalance measurements Other sensing methods are being developed, including (Gabai et al., 2001).

Recently, electrospinning has been used to produce polymeric nanofibers for application to sensing (Dai et al., 2004). Nanofibers made by electrospray have a high surface area and are looking for applications in sensors and catalysts. It has been reported that optical sensors based on electrospun nanofiber membranes have higher sensitivity and selectivity than film sensors for the detection of metal ions and nitro compounds (Lee et al., 2002, Wang et al. , 2002, Xianyan et al., 2002).

Therefore, the inventors of the present invention fabricated a new sensor electrode based on an electrospun nanofiber membrane of a composite of poly (vinylidene fluoride) and poly (aminophenylboronic acid) on an ITO glass plate and measured the glucose sensing ability of the nanofiber membrane. It was. As a result, it was confirmed that PVdF / PAPBA-NFM is not influenced by sensitivity and interference in the detection of glucose, and shows reproducible and storage stability.

Accordingly, an object of the present invention is to provide a functional nanofiber membrane and a biosensor using the same. More specifically, the present invention seeks to provide an enzyme-free amperometric glucose sensor.

Another object of the present invention is also nanofibers from a composite comprising poly (vinlylidene fluoride), PVdF) and poly (aminophenylboronic acid, PAPBA). It is intended to provide a method of making a membrane. More specifically, the present invention seeks to provide a method of making functional nanofiber membranes comprising electrospinning composites comprising PVdF and PAPBA.

In addition, another object of the present invention is to provide a glucose sensor which is PVDF / PAPBA-NFM produced by electrospinning and is not affected by sensitivity and interference, and exhibits reproducible and storage stability.

The present invention relates to a functional nanofiber membrane (nanofibrous membrane) and a biosensor using the same. More specifically, the present invention relates to enzyme-free glucose sensors, comprising poly (vinlylidene fluoride), PVdF and poly (aminophenylboronic acid) And nanofiber membranes prepared from composites comprising PAPBA) and their application to sensors.

The present invention further relates to a method for producing a functional nanofiber membrane comprising electrospinning a composite comprising PVdF and PAPBA and a method for producing an electrode for a biosensor comprising collecting it on a plate. .

Specifically, the present invention relates to a nanofiber membrane, which is prepared by electrospinning a mixture comprising poly (vinylidene fluoride) and poly (aminophenylboronic acid), preferably the poly (vinylidene fluoride) And poly (aminophenylboronic acid) at a ratio of 95 to 99 wt%: 5 to 1 wt%.

The present invention also relates to a sensor electrode characterized in that the nanofiber film is deposited on a plate. Preferably, the plate is characterized in that the indium tin oxide (ITO).

In addition, the present invention relates to a sensor comprising a sensor electrode in the biosensor through the current measurement, preferably characterized in that for detecting glucose.

The inventors of the present invention produced a nanofiber membrane (PVdF / PAPBA-NFM) of a composite including poly (vinylidene fluoride) and poly (aminophenylboronic acid) through a transfer spinning method. PVdF / PAPBA-NFM showed a good linear response in the detection of glucose in the 1-5 mM concentration range within a response time of less than 6 seconds. Glucose-sensing amperometric measurements of PVdF / PAPBA-NFM in the presence of common interferences such as uric acid, ascorbic acid and acetoaminophene Further experiments confirmed that these interferences do not overlap the current signal for glucose.

Therefore, PVdF / PAPBA-NFM was found to have a high selectivity for glucose. In addition, PVdF / PAPBA-NFM has high reproducibility and storage stability.

Hereinafter, a preferred embodiment of the present invention will be described in more detail.

Example

Example 1 Preparation of Reagents and Materials

3-aminophenylboronic acid, poly (vinylidene fluoride), glucose, acetaminophen, ascorbic acid and uric acid Analytical grades were used as received. Secondary distilled water was used for all experiments. Aqueous solutions of glucose were freshly prepared and used in phosphate buffer (pH = 7.5) when needed for the experiment. A glass plate coated with indium tin oxide (ITO) (specific surface resistance of about 10) was used to prepare the sensor electrode. Before each experiment, the ITO electrode was degreased with acetone and rinsed with distilled water.

Example 2 Fabrication of Sensor Electrode

Poly (aminophenylboronic acid) (PAPBA) was prepared by oxidative polymerization of 3-aminophenylboronic acid (50 mM in 1M HCl) with ammonium persulfate (0.1M in 1M HCl) at 5 ° C. The green precipitate, PAPABA, was filtered off, washed with 1M HCl and dried in a vacuum oven. Appropriate amounts of PVdF and PAPBA were dissolved in a DMF / acetone mixture (7: 3 v / v). Electrospinning of the mixed solution was performed at a flow rate of 10 mL / h with a voltage difference of 25 kV. The distance between the syringe tip and the collector was maintained at 15 cm. Mixed membranes were collected on an ITO glass plate (FIG. 1).

Example 3 Characterization

The shape of the sensor electrode (PVdF / PAPBA-NFM) was examined with a Field Radiation Scanning Electron Microscope (FESEM) Hitachi S-4300 with a field emission gun operated at 200 kV. Fourier transform infrared spectra were recorded using a Bruker IFS 66v FTIR spectrophotometer.

Example 4 Use of the Device

All electrochemical measurements were performed using the EG & G PAR 283 Electrochemical Analyzer. Electrocatalytic activity of the sensor electrode (PVdF / PAPBA-NFM) was measured using cyclic voltammetry in 1 M HCl with electrolyte. The amperometric response of the sensor electrode was recorded under steady-state conditions in phosphate buffer (pH = 7.5) by applying a constant voltage of 0.4 V to the working electrode. Amperometric experiments were performed in a standard single-compartment electrochemical cell comprising a sensor electrode, an SCE reference electrode and a platinum wire auxiliary electrode. When the ground current became stable, the glocose solution was injected into the electrolytic cell and its response was measured. For flow analysis, the relationship between current and time following the injection of various glucose concentrations at various concentrations in phosphate buffer (pH = 7.5) was recorded.

result

For sensors, sensitivity, selectivity and mechanical stability are essential. The inventors of the present invention produced a nanofiber PVdF / PAPBA membrane (PVdF / PAPBA-NFM) with a glucose biosensor. PVdF / PAPBA-NFM has a boronate group that senses glucose in PAPAB which is mechanically strongly immobilized into the PVdF matrix by electrospinning (FIG. 1).

1. Morphology and Microstructure of PVdF / PAPBA-NFM

FIG. 2 shows field emission scanning electron microscopy (FESEM) images of a nonwoven membrane of electrospinning of a PVdF / PAPBA composite membrane (FIG. 1) deposited on an ITO coated glass plate. Several interesting features have emerged in the form of electrospun PVdF / PAPBA composite membranes. FESEM images of PVdF / PAPBA complexes show that the complexes show nanofiber morphology. The fibers are almost uniform in shape with an average diameter of about 150 nm. Nanofibers are interconnected to form a network. The nanofiber surface of the composite is smooth. The morphological characteristics of PVdF / PAPBA-NFM differ significantly from electrospun PVdF membranes prepared under similar conditions.

The fibers of PVdF are stretched and straight and have an average diameter of about 450 nm (Kim et al., 2004). The average diameter of the PVdF membrane is much larger than the average diameter (about 150 nm) of the PVdF / PAPBA composite membrane. The small size of the nanofibers of PVdF / PAPBA provides a much larger surface area and allows the boronic acid groups present in PAPBA to act as nuclei for selecting and sensing glucose.

The interconnected network morphology of the PVdF / PAPBA complex results in intermolecular interactions between NH ₂ groups in PAPBA and CF groups in PVdF. The FT-IR spectrum of PVdF / PAPBA-NFM (FIG. 3, a) shows evidence of intermolecular interactions between PVdF and PAPBA. The FT-IR spectrum of PVdF / PAPBA-NFM shows characteristic bands corresponding to PVdF and PAPBA. Composite membranes are characterized by CF2 vibration (1410 cm ^-1 ), CF2 wagging (480 cm ^-1 ), BO stretching (1350 cm ^-1 ), BC stretching (1090 cm ^-1 ), and directional quinoid It has a spectral band corresponding to the CN stretch (1600 cm ^-1 ) of the imine (aromatic quiniod imine) Molecular interactions between PVdF and PAPBA can be clearly seen from shifts in CF2 stretch and CF2 shake band positions for each band in simple PVdF (FIG. 3, b). The presence of a band corresponding to quinoid imine stretch (about 1600 cm ⁻¹ ) in the FT-IR spectrum of PVdF / PAPBA-NFM indicates that PAPBA is in a self-doped state ( Deore and Freund, 2003).

2. Electrical Activity of PVdF / PAPBA-NFM

PVdF / PAPBA-NFM shows electrical activity. This cycles the potential between 0.0 V and 1.0 V versus a standard calomel electrode (SCE) at a scan rate of 50 mV / s, yielding a cyclic voltammogram (CV) of PVdF / PAPBA-NFM in 1 M HCl. The recorded record was confirmed through (Fig. 4). On the other hand, it should be noted that the electrospun PVdF film is insulated and does not exhibit any electrical activity.

The electrical activity of PVdF / PAPBA-NFM arises from the presence of PAPBA. During the anodic scan, the CV of PVdF / PAPBA-NFM shows two oxidation peaks at about 550 mV and 900 mV, in which the reduced aminophenyl boronic acid unit is the polaronic (benzene-based diamine) of PAPBA and Transformation into bipolaronic (quinone diimine) structures (Shoji and Freund, 2002).

During the reverse scan of the potential, the reduction peaks at 770 mV and 380 mV, corresponding to the transformation of bipolaronic to polaronic and to the reduced form of polaronic PAPBA, respectively, Was observed. PVdF / PAPBA-NFM thus shows the characteristics of a modified electrode with the ability to detect glucose.

3. Sensor Characteristics of PVdF / PAPBA-NFM

Sensitivity, selectivity and stability of PVdF / PAPBA-NFM as glucose sensors were established through successive electrochemical measurements.

3.1 Amperometric Response of PVdF / PAPBA-NFM

FIG. 5 shows the current-time profile obtained with PVdF / PAPBA-NFM vs. standard caramel electrode (SCE) during the continuous addition of 1 mM glucose in phosphate buffer (pH = 7.5) at an operating potential of 0.4V. Once the ground current became stable, glucose was added into the electrolyte (phosphate buffer) with stirring. During the first addition of 1 mM glucose to the electrolyte, a high peak current density (35 mA / cm ² ) was characteristic. The current response to the continuous addition of glucose was recorded. With each addition of glucose, the current at the fiber membrane electrode suddenly increases and reaches a stable value. Stable and fast amperometric response was observed with continuous infusion of glucose (FIG. 5). The time required to reach a stable response was less than 6 seconds, which is much lower than other types of glucose sensors (Kalayci et al., 2005, Kamenjicki and Asher, 2005). The inset of FIG. 5 shows the plot (response current versus concentration of glucose) during glucose detection.

A low detection limit of 0.01 mM glucose (signal-noise ratio S / N = 3) was noted. Thus, the fibrous membrane shows high sensitivity to glucose compared to other nanofiber glucose sensors (Yabuki et al., 2000 Chabuki et al., 2001, Yabuki and Mizutani, 2005, Yang et al., 2005).

3.2 Selectivity of PVdF / PAPBA-NFM

The selectivity to glucose of PVdF / PAPBA-NFM was tested by experimenting in the presence of a substance known as a glucose interference substance such as ascorbic acid (AA), acetoaminophene (AP) and uric acid (UA). UA and AA have been reported to interfere with electrochemical responses in the detection of glucose by enzyme-based and amperometric sensors (Park et al., 2003).

The amperometric current response of PVdF / PAPBA-NFM in a mixture with physiological levels of glucose, AA, AP and UA is shown (FIG. 6). To test the effect on the electrochemical reaction for glucose detection of the interfering substances, the concentration of glucose was kept at 5 mM and UA, AA and AP at 0.1 M each.

When UA, AA and AP solutions were added to the glucose solution, the interference in the current signal was negligible (FIG. 6). This indicates a high selectivity of PVdF / PAPBA-NFM.

The high selectivity for glucose is believed to be due to the possible complexation between glucose and boronic groups in PAPBA. Previous studies on potentiometric sugar sensors by PAPBA-based sensors showed that the complexation between boronic acid and diols in the presence of F ^- ions was remarkable, which led to high selectivity for sugars. (Shoji and Freund, 2002). F ⁻ ions lead to the formation of boron anions as intermediates. When the F ⁻ ions were bonded to the boron atom, the Sp ² hybrid boron was changed to the Sp ³ form, and the modified boron group could form a complex with the diol or saccharide.

In the present invention, no F ⁻ ions were added externally during the manufacture of the glucose sensor. Rather, there is a molecular level interaction between the CF group of PVdF and PAPBA in PVdF / PAPBA-NFM that ultimately leads to complex formation with glucose (FIG. 1). FT-IR spectra (FIG. 3) and FESEM analysis (FIG. 2) data are consistent with the intermolecular interactions between PVdF and PAPBA groups. The interconnected forms of PVdF / PAPBA-NFM are the result of molecular interactions (FIG. 2). FIG. 1 (Scheme 2) shows a possible complexation between boronic acid of PAPBA group and hydroxyl group of glucose. As apparent from the current response (FIG. 4), the high selectivity for glucose of PVdF / PAPBA-NFM is believed to be due mainly to this complexation.

3.3. Flow injection analysis

Flow injection analysis has been widely adopted in analytical chemistry due to features such as low sample consumption, reproducibility of results, high throughput and versatility. 7 shows the amperometric response of PVdF / PAPBA-NFM at increasing concentrations of glucose solution. The current response increases linearly with the concentration of glucose (Figure 7). It is shown that the response current corresponding to glucose detection increases proportionally with increasing glucose concentration. It is also evident that PVdF / PAPBA-NFM provides good reproducibility in the repeated detection of glucose.

Interestingly, there is no memory effect on increasing glucose concentration in the response. PVdF / PAPBA-NFM therefore has sufficient intra- and inter-electrode reproducibility for current signals.

Nanofibers are expected to have high surface areas. This offers the possibility for a large number of active sites in the present invention that can sense glucose. PVdF / PAPBA-NFM is suitable for dynamic and continuous monitoring compared to previously reported PAPBA based glucose sensors (Shoji and Freund, 2001, Shoji and Freund, 2002). For Freund's reported PAPBA-based glocose sensors (Shoji and Freund, 2002), sensitivity is caused by inclusion of F ^- ions into the PAPBA as inclusions. Under the dynamic conditions of detecting glucose, there is a possibility of removing F ^- ions from the PAPBA film, so the F ^- ions are leached from the sensor over long periods of use, which will significantly reduce the sensitivity of the glucose sensor.

In the case of the present invention, PVdF has a CF group and has a form connected to each other in the complex, so that the F ^- ion can be in close proximity to the boron atom to provide a bond with glucose. Therefore, there is no room for problems due to the loss of F ^- ions. Hydrodynamic experiments on the continuous flow of glucose showed that PVdF / PAPBA-NFM is ideally suited for the detection of glocose in continuous flow.

3.4. PVdF / PAPBA-NFM Stability

After storage of PVdF / PAPBA-NFM for 10 days in 298K air, the stability of PVdF / PAPBA-NFM was measured by measuring the steady-state current response of the sensor in phosphate buffer (pH = 7.5) containing 10 mM glocose. Tested (FIG. 8).

The sensor electrodes retained 90% of their initial activity after 10 days and showed a good response to glocose.

PVdF / PAPBA-NFM prepared by the electromagnetic radiation of the present invention and the sensor electrode using the same are not affected by sensitivity, interference, and reproducibility and storage stability in detecting glucose. The predominant performance of these nanofibrous membranes is due to their large area and active sites that can detect glocose.

In addition, the electron emission membrane glucose sensor of the present invention is ideal for detecting glucose in a moving flow. In addition, the electrospinning technology applied to the present invention may be used to manufacture other biosensors by loading a sensing medium in the fiber substrate.

references

Adzic, R. R., Hsiao, M. W., Yeager, E. B., 1989. Electrochemical oxidation of glucose on single crystal gold surfaces, J. Electroanal. Chem. 260, 475-485.

Bae, I. T., Yeager, E., Xing, X., Liu, C. C., 1991. In situ infrared studies of glucose oxidation on platinum in an alkaline medium. J. Electroanal. Chem. 309, 131-145.

Badugu, R .; Lakowicz, J. R .; Geddes, C. D. 2004. Noninvasive continuous monitoring of physiological glucose using a monosaccharide-sensing contact lens. Anal. Chem. 76, 610-618.

Badugu, R., Lakowicz, J. R., Geddes, C. D., 2005. Boronic acid fluorescent sensors for monosaccharide signaling based on the 6-methoxyquinolinium heterocyclic nucleus: progress toward noninvasive and continuous glucose monitoring, Bioorganic. Med. Chem. 13, 113-119.

Cesare, N. D., Lakowicz, J. R., 2002. New sensitive and selective fluorescent probes for fluoride using boronic acids. Anal. Biochem. 301, 111-116.

Cui, G., Yoo, J. H. l., Woo, B. W., Kim, S. S., Cha, G. S., Nam, H., 2001. Disposable amperometric glucose sensor electrode with enzyme-immobilized nitrocellulose strip, Talanta, 54, 1105-1111.

Dai, L. Reneker, D. H., In: Wang, Z. L., Editor, Nanowires and Nanobelts, Volume II Materials, Properties and Devices, Kluwer Academic Publishers, Dordrecht (2004).

Deore, B., Freund, M. S., 2003. Saccharide imprinting of poly (aniline boronic acid) in the presence of fluoride, Analyst, 128, 803806.

Forrow, N. J., Walters, S. J., 2004. Transition metal half-sandwich complexes as redox mediators to glucose oxidase. Biosens. Bioelectron. 19, 763-770.

Gabai, R., Sallacan, N., Chegel, V., Bourenko, T., Katz, E., Willner, I., 2001.Characterization of the swelling of acrylamidophenylboronic acid-acrylamide hydrogels upon interaction with glucose by faradaic impedance spectroscopy , chronopotentiometry, quartz-crystal microbalance (QCM), and surface plasmon resonance (SPR) experiments, J. Phys. Chem. B. 105, 8196-8202

Kalayci, S., Somer, G., Ekmekci, G., 2005. Preparation and application of a new glucose sensor based on iodide ion selective electrode, Talanta 65, 87-91.

Kamenjicki, M., Asher, S. A., 2005. Epoxide functionalized polymerized crystalline colloidal arrays. Sensors. Actuators B. 106, 373-377.

Kim, J. R., Choi, S. W., Jo, S. M., Lee, W. S., Kim, B. C., 2004. Electrospun PVdF-based fibrous polymer electrolytes for lithium ion polymer batteries, Electrochim. Acta 50, 69-75.

Lee, M., Kim, T., Kim, KH, Kim, JH, Choi, MS, Choi, HJ, Koh, K., 2002.Formation of a self-assembled phenylboronic acid monolayer and its application toward developing a surface plasmon resonance-based monosaccharide sensor, Anal. Biochem. 310, 163-170.

Lee, S. H., Ku, B. C., Wang, X., Samuelson, L.A., Kumar, J., 2002. Design, synthesis and electrospinning of a novel fluorescent polymer for optical sensor applications, Mater. Res. Soc. Sympo. Proceed. 708, 403-408.

Park, S., Chung, T. D., Kim, H. C., 2003. Nonenzymatic glucose detection using mesoporous polatinum, Anal. Chem. 75, 3046-3049.

Pringsheim, E., Terpetschnig, E., Piletsky, S. A., Wolfbeis, O. S., 1999. A polyaniline with near-infrared optical response to saccharides. Adv. Mater. 11, 865-868.

Shinmori, H., Takeuchi, M., Shinkai, S., 1995. Spectroscopic sugar sensing by a stilbene derivative with push (Me2N-)-pull ((HO) 2B-)-type substituents, Tetrhedron 51, 1893-1902.

Shoji, E., Freund, M. S., 2001. Potentiometric sensors based on the inductive effect on the pKa of poly (aniline): A nonenzymatic glucose sensor J. Am. Chem. Soc. 123, 3383-3384.

Shoji, E., Freund, M. S., 2002. Potentiometric saccharide detection based on the pKa changes of poly (aniline boronic acid), J. Am. Chem. Soc. 124, 12486-12493.

Taylor, S. I., 1999. Deconstructing type 2 diabetes. Cell 97, 9-12.

Wang, J., Jin, S., Wang, B., 2005. A new boronic acid fluorescent reporter that changes emission intensities at three wavelengths upon sugar binding. Tetrahedron Letters 46, 7003-7006.

Wang, X., Lee, S. H., Drew, C., Senecal, K. J., Kumar, J., Samuelson, L. A., 2002. A Highly sensitive optical sensors using electrospun polymeric nanofibrous membranes, Mater. Res. Soc. Sympo. Proceed. 708, 397-402.

Xianyan, W., Drew, C., Lee, S. H., Senecal, K. J., Kumar, J., Samuelson, L. A., 2002. Electrospun nanofibrous membranes for highly sensitive optical sensors Nano Lett. 2, 1273 -1275.

Yabuki. S., Mizutani, F., 2005. Preparation of amperometric glucose sensor based on electrochemically polymerized films of indole derivatives, Sensors. Actuators B. 108, 651-653.

Yabuki, S., Mizutani, F., Hirata, Y., 2000. Preparation of a glucose-sensing electrode based on glucose oxidase-attached polyion complex membrane containing microperoxidase and ferrocene. Electrochemistry 68, 853-855.

Yabuki, S., Mizutani, F., Hirata, Y., 2001. Glucose-sensing electrode based on glucose oxidase-attached polyion complex membrane containing peroxidase and ferrocene, Electroanalysis 13, 380-383.

Yamazaki, T., Kojima, K., Sode, K., 2000. Extended-range glucose sensor employing engineered glucose dehydrogenases, Anal. Chem. 72, 4689-4693.

Yang, H., Zhu, Y., 2006. Size dependence of SiO 2 particles enhanced glucose biosensor, Talanta 68, 569574.

Yeo, I. H., Johnson, D. C., 2000. Anodic response of glucose at copper-based alloy electrodes. J. Electroanal. Chem. 484, 157-163.

Yeo, I. H., Johnson, D. C., 2001. Electrochemical response of small organic molecules at nickelcopper alloy electrodes. J. Electroanal. Chem. 495, 110-119.

Yu, J., Liu, S., Ju, H., 2003. Glucose sensor for flow injection analysis of serum glucose based on immobilization of glucose oxidase in titania solgel membrane, Biosens. Bioelectron. 19, 401-409

Claims (6)

A nanofiber membrane, which is prepared by electrospinning a mixture comprising poly (vinylidene fluoride) and poly (aminophenylboronic acid). The nanofiber membrane of claim 1, wherein the poly (vinylidene fluoride) and the poly (aminophenylboronic acid) are included in a ratio of 95 to 99 wt%: 5 to 1 wt%. A sensor electrode, wherein the nanofiber film according to any one of claims 1 to 2 is deposited on a plate. 4. The sensor electrode according to claim 3, wherein the plate is indium tin oxide (ITO). A current measuring biosensor comprising a sensor electrode according to claim 3. 6. The sensor of claim 5, wherein said sensor senses glucose.

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