CN113433190B

CN113433190B - Biological conductive composite film and application thereof in detecting glucose

Info

Publication number: CN113433190B
Application number: CN202110539923.4A
Authority: CN
Inventors: 臧广超; 张玉婵; 杨博翔; 隋玖锡; 朱姝
Original assignee: Chongqing Medical University
Current assignee: Chongqing Medical University
Priority date: 2021-05-18
Filing date: 2021-05-18
Publication date: 2023-05-30
Anticipated expiration: 2041-05-18
Also published as: CN113433190A

Abstract

The invention belongs to the field of materials, and particularly relates to a biological conductive composite membrane and application thereof in detecting glucose. The invention improves the material of the SS/DHMC film to obtain good electrochemical performance, and is used for manufacturing a sensor to detect glucose in sweat. The biological conductive composite membrane SS/DHMC/10% AuNPs-AMWCNTs has good electrochemical stability and temperature stability, can be directly used as a flexible electrode of a glucose detector, and can generate electrochemical response by catalyzing glucose to generate electrochemical change values to detect the concentration of the glucose.

Description

Biological conductive composite film and application thereof in detecting glucose

Technical Field

The invention relates to the field of materials, in particular to a biological conductive composite membrane and application thereof in detecting glucose.

Background

Diabetes is an incurable disease at present, and the blood sugar level of a diabetic patient is monitored in real time, so that the serious illness state and the damage of cardiovascular and cerebrovascular diseases can be avoided. Therefore, accurate monitoring of blood glucose has important scientific and technical significance in clinical diagnosis of controlling diabetes. In addition, rapid, sensitive and reliable glucose sensing is also important for environmental pollution control, biotechnology and analytical applications in the food industry. Plasma glucose is the main source of glucose in sweat, which can reflect the human blood glucose state: 300mg/dL glucose in blood corresponds to 0.3mM glucose in sweat (normal range is 0.1-50 mg/dL).

Blood glucose is monitored clinically, typically using a blood glucose meter. Blood glucose meters fall into two categories: photoelectric type and electrode type; the latter is widely studied because of its more scientific testing principle. Thus, electrochemical-based electrode-type blood glucose meters represent 85% of the commercial hand-held biosensor market. Because blood glucose meters rely on invasive blood tests, this type of test is often accompanied by pain and discomfort associated with repeated blood draws. With the development of technology, the miniature, portable, stable and noninvasive flexible test equipment can better meet the demands of people. While the research on glucose sensors also goes from the first generation of enzyme sensors to the fourth generation of non-enzyme glucose sensors; continuous research is being conducted to realize glucose sensing technology with high sensitivity, high selectivity, low detection limit, convenience and low cost. Despite many research efforts in the field of non-enzymatic glucose detection, monitoring glucose under physiological conditions remains a great challenge, limiting their clinical applicability. On the one hand, when certain noble metal materials interact with glucose, the physical and chemical properties of the noble metal materials change to generate an electron transfer process on the surface of the electrode, so that the electrode generates electrochemical response to the glucose to realize the detection of the glucose. For example, pt and Pb materials exhibit high catalytic performance on glucose molecules in neutral buffers, and the current is varied by catalytic oxidation of glucose to form gluconolactone to produce electrode-to-metal electron transfer. However, cl in the neutral buffer during the catalytic oxidation of glucose ^- And the intermediate product can be adsorbed on the surface of the electrode, resulting in poor sensitivity and stability, which are unfavorable for the electrochemical reaction of the sensing interface. Although inexpensive copper-based hybrid materials have also been developed that have high glucose sensing performance under neutral conditions, detection in sweat is still not achievable due to their limit of detection. In addition, the preparation process of the hybrid nanomaterial is more complex and time consuming than the preparation process of a single metal.

Therefore, innovation of materials is needed to overcome the above technical problems, so that a glucose sensor with high sensitivity, strong stability and low manufacturing cost is manufactured, the cross section of the SS/DHMC film is of a porous structure, the surface is smooth, the potential of good mechanical property and water absorption property can be shown, the potential of effective electron transfer is provided, but the conductivity is poor, and the material improvement of the SS/DHMC film is needed to obtain good electrochemical property for manufacturing the sensor.

Disclosure of Invention

The invention aims to solve the problems, and provides a biological conductive composite membrane, which can be directly used as a flexible electrode to prepare a sensor for detecting glucose by utilizing the catalytic performance and good electrochemical performance of the biological conductive composite membrane on glucose.

The invention aims to provide a biological conductive composite film which has good catalytic performance on glucose.

A bioelectrical conductive composite membrane consisting of sericin (SS), dialdehyde Hydroxypropyl Methylcellulose (DHMC), auNPs and aminated multiwall carbon nanotubes (AMWCNTs).

Specifically, the mass ratio of the gold nanoparticle modified aminated multi-wall carbon nanotubes (AuNPs-AMWCNTs) in the composite film is 10%.

The electrochemical response of the composite membrane with 10% of gold nanoparticle modified amino carbon nanotube content in PBS environment with pH=7.4 is maximum, and the composite membrane has great potential for detecting glucose, good selectivity and good temperature stability.

The second purpose of the invention is to protect the glucose sensor prepared by the biological conductive composite film in the technical scheme.

Specifically, the flexible electrode of the glucose sensor is SS/DHMC/10% AuNPs-AMWCNTs.

The invention further aims to provide a method for detecting that the upper limit of glucose reaches 14mM by using the biological conductive composite membrane in the scheme, and the specific technical scheme is that the mass ratio of AuNPs-AMWCNTs is 10%.

The fourth object of the present invention is to provide a method for detecting glucose by using the biological conductive composite membrane described in the above technical solution, which comprises the following specific technical solutions:

according to the method for detecting glucose by using the biological conductive composite membrane in the technical scheme, the biological conductive composite membrane catalyzes glucose to generate electrochemical response, and the glucose concentration is obtained according to the electrochemical change value generated by the electrochemical response.

Specifically, the mass ratio of the AuNPs-AMWCNTs is 10%.

Specifically, the electrochemical change value is a current change value or a voltage change value.

Specifically, the detection temperature is 20-40 ℃.

Specifically, the detection environment Ph value is 7-7.4.

The fifth purpose of the invention is to utilize the biological conductive composite film in the technical proposal to detect glucose from sweat interfering substances, and the specific technical proposal is as follows:

the method for detecting glucose from sweat interfering substances by using the biological conductive composite membrane in the technical scheme comprises the steps of catalyzing glucose to generate electrochemical response, and measuring an electrochemical change value generated by the electrochemical response by using a voltammetry to obtain glucose concentration; the biological conductive composite film is SS/DHMC/10% AuNPs-AMWCNTs; the sweat interfering substance is ascorbic acid and/or NaCl and/or KCl and/or urea and/or dopamine.

In particular, the method may also detect glucose from other sugars, including sucrose and fructose.

Specifically, the temperature of the biological conductive composite film in the glucose detection process is 20-40 ℃, and the detection Ph value is 7.4.

Specifically, the voltammetry includes a DPV method and a CV method.

Specifically, when the voltammetry is a CV method, the upper limit concentration of glucose detected by the method is 14mM.

The invention has the advantages that:

(1) The biological conductive composite membrane SS/DHMC/10% AuNPs-AMWCNTs has good electrochemical stability and temperature stability, can be directly used as a flexible electrode of a glucose detector, and can generate electrochemical response by catalyzing glucose to generate electrochemical change values to detect the concentration of the glucose.

(2) The SS/DHMC/10% AuNPs-AMWCNTs composite membrane has extremely high sensitivity, can be used for detecting trace glucose in sweat, and has the upper limit of 14mM for detecting glucose.

(3) The conductive composite film also has good selectivity to glucose, can resist the interference of ascorbic acid, naCl, KCl, urea and dopamine in sweat, and can resist the interference of other substances such as sucrose and fructose.

Drawings

FIG. 1 is an SEM characterization of an SS/DHMC composite membrane, an SS/DHMC/10% AMWCNTs composite membrane, an SS/DHMC/10% AuNPs-AMWCNTs composite membrane

FIG. 2 is a Fourier infrared plot of composite membranes of SS, SS/DHMC/10% AMWCNTs, SS/DHMC/10% AuNPs-AMWCNTs

FIG. 3 is a CV diagram of AuNPs-AMWCNTs quality optimization

FIG. 4 is a DPV chart of AuNPs-AMWCNTs quality optimization

FIG. 5 is a pH-optimized DPV graph of SS/DHMC/10% AuNPs-AMWCNTs composite Membrane

FIG. 6 is a graph of DPV peak voltage at different pH

FIG. 7 is a graph of DPV peak current for different pH values

FIG. 8 is a CV diagram of scan rate optimization

FIG. 9 is a current linear graph of redox peaks in sweep rate optimization

FIG. 10 is a graph showing CV characterization of different composite membranes

FIG. 11 is a CV diagram of SS/DHMC/10% AuNPs-AMWCNTs composite Membrane

FIG. 12 is a linear plot of redox peaks in CV

FIG. 13 is a DPV graph of an SS/DHMC/10% AuNPs-AMWCNTs composite Membrane

FIG. 14 is a DPV linear graph

FIG. 15 is a graph showing the selectivity of SS/DHMC/10% AuNPs-AMWCNTs composite membranes

FIG. 16 is a graph of interference immunity of SS/DHMC/10% AuNPs-AMWCNTs composite membranes

FIG. 17 is a graph showing the reproducibility of SS/DHMC/10% AuNPs-AMWCNTs composite membranes

FIG. 18 is a reproduction of an SS/DHMC/10% AuNPs-AMWCNTs composite film

FIG. 19 is a graph showing the folding stability of SS/DHMC/10% AuNPs-AMWCNTs composite membranes

FIG. 20 is a graph showing the temperature stability of SS/DHMC/10% AuNPs-AMWCNTs composite membranes

Detailed Description

The present invention will be further described in detail by the following examples, it being understood that the specific examples described herein are intended to be illustrative only and not to be limiting of the invention, and it will be understood by those skilled in the art that the details and forms of the technical solution of the present invention may be modified or substituted without departing from the structural spirit and scope of the invention, but that the modifications and substitutions fall within the scope of the invention.

Example 1 Material analysis

Characterization analysis of materials

As shown in fig. 1 (a, b), at 5kV, the cross section of the SS/DHMC film is porous, has a smooth surface, can exhibit good mechanical properties and the potential of water absorption, and has the potential of effectively transferring electrons. FIG. 1 (c, d, e, f) shows the cross-section and surface of SS/DHMC/AMWCNTs and SS/DHMC/10% AuNPs-AMWCNTs films, on which gold nanoparticles are embedded in the pores of the films, which greatly improves the conductivity of the films. Gold nanoparticles exposed on the surface of the membrane have the potential to have a better catalytic effect on glucose. In addition, both surfaces were rougher than the SS/DHMC film, and the SS/DHMC/10% aunps-AMWCNTs film had distinct gold nanoparticles on the surface.

Fourier transform infrared spectroscopy

As shown in FIG. 2, 5 peaks appear in the FT-IR spectrum, corresponding to A, B, I, II and III, respectively, of sericin amide. Corresponding peaks are 3277, 3080, 1620, 1515 and 1240cm respectively ^-1 . As can be seen from FT-IR spectral comparison of sericin and SS/DHMC film, 1620cm of sericin after crosslinking with DHMC ^-1 (amide I)、1515cm ^-1 (amide II) and 1240cm ^-1 The peak of (amide III) was at 1619cm ^-1 、1519cm ^-1 And 1243cm ^-1 And (5) moving. At 1620cm ^-1 Peak change at 1515cm is related to c=o stretching vibration (amide I) ^-1 The peak change at this point is usually related to the N-H bending vibration (amide II) and is 1397cm due to C-N stretching ^-1 1402cm to ^-1 And (5) moving. 1240cm of C-N bond and N-H bond induced by stretching ^-1 Variation of peak at (amide III), additionally 1732cm for SS/DHMC membranes ^-1 The peak change at this point demonstrates the disappearance of the aldehyde groups. And 1732cm ^-1 The cross-linking reaction of the sericin with DHMC occurred in the composite film compared to the sericin peak at the place, however, we did not find the frequency band of c=n (schiff base) vibration at 1660cm "1. This is probably because it is masked by the amide I of the sericin. FT-IR spectrum for SS/DHMC/10% AMWCNTs film was found at 1732cm ^-1 The peak at the rise, indicating that the composite membrane after addition of AMWCNTs has more aldehyde groups distribution. Since the infrared absorption cross section of the aminated carbon nanotube is much smaller than that of sericin and DHMC, we did not observe peaks of the aminated carbon nanotube. Furthermore, the peak wavenumbers of the corresponding amidi, II, III sericin were slightly increased in the FT-IR spectrum of SS/DHMC/10% AMWCNTs film, and the change in these peaks confirmed that incorporation of AMWCNTs slightly shifted from random coil to α -helix structure and did not cause shift of sericin secondary structure. Meanwhile, for the FT-IR of the SS/DHMC/10% AuNPs-AMWCNTs film, the wave number is slightly reduced compared with that of the SS/DHMC film, and the influence on the secondary structure of the sericin is small.

Example 2 electrochemical Properties of bioconducting composite films

Optimization of conductive materials

First, we optimized the content of the aminated carbon nanotubes modified by adding gold nanoparticles with different contents. As shown in FIG. 3, by performing cyclic voltammetry under PBS condition with pH=7.4, it can be found that with the addition of AuNPS-AMWCNTs conductive material, which has good conductivity due to AMWCNTs (oriented multi-wall nanotubes) and AuNPs, with the increase of material quality, the oxidation peak of cyclic voltammogram increases, the reduction peak decreases, the oxidation peak is about 0.04V, the reduction peak is about-0.3V, and the oxidation and reduction peaks of the content ratio of four different conductive materials are very similar, which indicates that electrochemical response is continuously increased, but in the composite film with 20% contentThe reaction is minimal. Furthermore, the optimal electrochemical response is a composite membrane with a content of 10% aunps-AMWCNTs. These results indicate that the addition of an appropriate conductive material can improve the electrochemical response of the composite membrane to some extent, enhance the conductivity of the composite membrane, and enhance the application of glucose detection. Meanwhile, as shown in FIG. 4, the current peak of the composite film with 10% gold nanoparticle modified aminated carbon nanotube content is maximum, about 1.2e, by further analyzing the contents of different conductive substances by differential pulse voltammetry ^-5 The peak voltage of the composite film with the four different conductive material contents is the same and is about-0.1V. From the data graph curves obtained in the optimization of the two different methods of CV and DPV, we can infer that the electrochemical response of the composite membrane with 10% gold nanoparticle modified carbon nanotube content is maximum in PBS environment with ph=7.4, and has great potential for detecting glucose.

pH optimization

After optimizing the content of the conductive material to obtain the optimal flexible electrode, the pH optimization research is carried out. The optimal pH detection environment is observed by examining the electrochemical response at different pH values. The pH of the PBS was adjusted to 6.2,6.6,7.0 and 7.4. From fig. 5-7 we can find that: as the pH increases, the peak potential gradually shifts to a negative potential, and the change in voltage value decreases linearly, indicating the presence of hydrogen ion transfer in the electrochemical reaction. For this phenomenon of change in peak potential, we can analyze on the basis of Mauro Pasta et al, and we speculate that in PBS, au (OH) ads and hydrogen ions may be formed on the surface of gold nanoparticles by a simple dehydrogenation reaction, and the substance to be tested is further oxidized to form glucolactone, similar to the reaction of Pt.

The main reaction equation is as follows:

meanwhile, the composite film had the highest current at ph=7.0, and the peak current was 1.6e ^-5 About A. Since human sweat is almost neutral, ph=7 is considered to be the optimal pH environment at which subsequent experiments were conducted.

Sweep rate optimization

We scanned SS/DHMC/10% AuNPs-AMWCNTs films by CV method at a scan rate of 50-500 mV/s. It can be found in fig. 8 that as the scanning rate increases, the current response of the conductive composite film increases, and a pair of redox peaks occur. This is an effective electron transfer effect of AuNPs-AMWCNTs. However, as the scan rate increases, the redox peak position gradually changes. This proved to be a quasi-reversible process. The regression curve function between the square root of the scan rate and the redox peak current is plotted, and the anodic peak R is shown in FIG. 9 ² =0.97, cathode peak R ² =0.97. It was demonstrated that the electrode reaction was not a single diffusion-controlled process, which could be explained by glucose being adsorbed after diffusion to the electrode surface.

Glucose detection

The electrocatalytic activity of SS/DHMC/AuNPs-AMWCNTs composite membranes on glucose oxidation was examined by using a three electrode system with a scan rate of 100mV/s in PBS at ph=7.4. FIG. 10 is a Cyclic Voltammogram (CVs) of an SS/DHMC film, an SS/DHMC/10% AMWCNTs film, and an SS/DHMC/10% AuNPs-AMWCNTs film, respectively, with no 2mM glucose concentration added to 0.1M PBS, at a potential ranging from-0.55V to 0.65V. All three composite membranes showed a pair of redox peaks. The oxidation-reduction peaks are about 0.1V and-0.4V, respectively.

By adding 2mM glucose concentration before and after the SS/DHMC/10% AMWCNTs film and the SS/DHMC film in 0.1M PBS, the oxidation peak and the reduction peak of CV did not change with the increase of glucose concentration, as can be seen in FIG. 10. And for the SS/DHMC/10% AuNPs-AMWCNTs composite membrane, when the concentration of 2mmol glucose is added, the response of an oxidation peak and a reduction peak is obviously enhanced, which shows that the composite membrane has good catalytic performance on glucose.

In addition, as the electrochemical response of the three composite films can be analyzed through the area size of the cyclic voltammogram, the composite films with the electrochemical response from large to small can be respectively an SS/DHMC film, a film added with 10% of AMWCNT content and a film added with 10% of AuNPs-AMWCNT content by comparing the detection effects of the three films on glucose, and the film with 10% of AuNPs-AMWCNT content can be obtained to have excellent electrochemical performance and glucose detection capability.

FIGS. 11 and 12 are CV values of SS/DHMC/10% AuNPs-AMWCNTs membranes at different glucose concentrations from 0mM to 14mM, with a linear increase in oxidation peak current and a linear decrease in reduction peak current with a linear increase in glucose concentration. The oxidation peak was 0.1V, and the reduction peak was about-0.3V. The current linearly increasing R-square values for the oxidation and reduction peaks were 0.992 and 0.999, respectively. Increasing the glucose concentration did not improve the peak current response of CV when the glucose concentration was measured at 14mM. As can be seen, the upper limit of detection of glucose by SS/DHMC/10% AuNPs-AMWCNTs membrane was 14mM.

In addition, fig. 13 and 14 show the linear effect of the composite membrane on the DPV method for detecting glucose. By analyzing the current value of the peak DPV, two different linear relations were obtained, a larger slope (r2=0.989) in the range 25 μm to 100 μm and a smaller slope (r2=0.9995) in the range 100 μm to 400 μm. There are two linearities in some of the previous work, which may be due to the ability of gold nanoparticles in the composite membrane to adsorb glucose molecules. In the detection of low concentration glucose, only a small amount of glucose can be adsorbed on the surface of gold nanoparticles, but a large number of sites make it highly sensitive. In the detection of high-concentration glucose, a large amount of glucose molecules are adsorbed on the surfaces of the gold nanoparticles, so that the active sites of the gold nanoparticles are reduced and the sensitivity of the gold nanoparticles is reduced.

We examined the linearity of glucose by DPV and CV methods, respectively. Since DPV is more sensitive than CV, it can provide good glucose linearity detection at lower concentrations, while CV method can detect higher concentrations of analyte and can perform linearity detection. The CV test resulted in a greater linearity of the glucose range than the DPV test.

Selectivity and interference resistance

Sweat contains very little glucose, about 1% to 2% of blood glucose levels, and human sweat contains sodium chloride and urea, which interfere with the detection of glucose. Thus, the selectivity and tamper resistance of sweat sensors to glucose sweat sensors to other disturbances is a very important property. A good method of detecting the glucose content in sweat is to use a sweat glucose sensor that reacts more strongly to glucose than other common interferents. The concentration of other interferents in sweat was much higher than the actual interferent concentration, with other interferents in sweat being lower than glucose. The selectivity of SS/DHMC/10% AuNPs-AMWCNTs membrane for glucose was further determined by high concentration interference detection.

10% SS/DHMC/AuNPs-AMWCNTs films were tested with DPV and 2mM (ascorbic acid, naCl, KCl, urea and dopamine) and 0.2mM glucose were added, respectively. As shown in the results of FIG. 15, the electrochemical response of the SS/DHMC/10% AuNPs-AMWCNTs membrane was higher after the addition of 0.2mM glucose than after the addition of 2mM interferents. The composite membrane has better selectivity to glucose, probably due to the good catalytic effect of the nano gold on glucose. In addition to detecting interfering substances in sweat, we tested for sugars other than glucose, such as sucrose and fructose. Their electrochemical reaction is much smaller than glucose. The electrochemical responses of the high concentration substances are smaller than those of low concentration glucose, and the SS/DHMC/10% AuNPs-AMWCNTs composite membrane has good selectivity on glucose.

The anti-interference can be detected by adding glucose and anti-interference substances at the same time. The current difference after addition of the interferents together with glucose is not much different from that when glucose was added alone as shown in FIG. 16.

Stability and reproduction form

Has important significance on the stability and repeatability of the sensor. Stability studies were performed weekly for one month. In the case of detecting the peak currents of 5 times without 0.2mmol glucose and without 0.2mmol glucose in PBS (ph=7.0) of ph=7.0 with DPV as shown in fig. 17, it was found that the peak currents of 0mmol and 0.2mmol were different by not more than 10% in the case of 5 times. Experiments prove that the composite membrane has good electrochemical stability in a long time of one month.

While at the same time for the purpose of synthesizing film repeatability. 8 identical SS/DHMC/10% AuNPs-AMWCNTs films with an area of 1cm x 1cm were prepared, and the peak currents of these composite films in the voltage range of-0.6V to 0.6V were obtained by DPV electrochemical method. DPV was performed on 8 composite films by constructing 0mmol and 0.2mmol glucose solutions, respectively, and the current values of the DPV peaks were recorded, as shown in FIG. 18, with peak currents differing by no more than 5%. Experiments prove that the composite membrane has good reproducibility in glucose detection.

Furthermore, we have performed bending of the membrane and tested its electrochemical stability. The composite membrane was folded into u-shape with forceps and was subjected to electrochemical detection by DPV method for 0, 50, 100, 150 and 200 times, respectively. As can be seen from fig. 19, the peak current hardly changed in the DPV detection of different folding times. The folding effect of the nano-gold modified amino carbon nano-tube composite film on the current conduction is not great. This is because the nanogold-modified amino carbon nanotubes can be well fixed in the composite film and do not vary with the number of film folds. Therefore, the composite membrane has good electrochemical stability and can be directly used as a flexible electrode.

Furthermore, we have studied the effect of different temperatures on the composite membrane. Since the composite membrane is mainly composed of protein and cellulose, excessive temperature may cause the composite membrane to decompose. Therefore, we studied the temperature stability of composite films with temperatures between 20 and 40 using the DPV method. As shown in fig. 20, the peak current of the composite film does not change much with increasing temperature, which proves that the electrochemical detection has good stability in a certain temperature range, in part, due to good thermal conductivity of the carbon nanotubes. The excellent stability at different temperatures demonstrates the good temperature stability of the material.

The foregoing description of the preferred embodiments of the invention is not intended to limit the invention to the precise form disclosed, and any such modifications, equivalents, and alternatives falling within the spirit and scope of the invention are intended to be included within the scope of the invention.

Claims

1. The bioelectric composite membrane is characterized by comprising sericin SS, dialdehyde hydroxypropyl methylcellulose DHMC, auNPs and AMWCNTs.

2. The glucose sensor prepared by the biological conductive composite membrane of claim 1.

3. The method for detecting glucose with the biological conductive composite membrane reaching the upper limit of 14mM according to claim 1, wherein the mass ratio of AuNPs-AMWCNTs in the composite membrane is 10%.

4. The method for detecting glucose by using the biological conductive composite membrane according to claim 1, wherein the biological conductive composite membrane catalyzes the electrochemical response of glucose, and the glucose concentration is calculated according to the electrochemical change value generated by the electrochemical response.

5. The method of claim 4, wherein the electrochemical change is a current change or a voltage change.

6. The method for detecting glucose from sweat interfering substances by using the bioelectric conductive composite membrane according to claim 1, wherein the bioelectric conductive composite membrane catalyzes glucose to generate electrochemical response, and electrochemical change value generated by the electrochemical response is measured by using voltammetry to obtain glucose concentration; the biological conductive composite film is SS/DHMC/10% AuNPs-AMWCNTs; the sweat interfering substance is ascorbic acid and/or NaCl and/or KCl and/or urea and/or dopamine.

7. The method of claim 6, wherein the method further detects glucose from other sugars, including sucrose and fructose.

8. The method of claim 6, wherein the temperature during glucose detection by the bioconducting composite membrane is between 20 ℃ and 40 ℃.

9. The method of claim 6, wherein the voltammetry comprises a DPV method and a CV method.

10. The method of claim 9, wherein when the voltammetry is CV, the method detects glucose at an upper concentration of 14mM.