Chitosan intercalation modified montmorillonite / carboxylated multi-walled carbon nanotube composite material as well as preparation method and application thereof

Abstract

The invention provides a chitosan intercalation modified montmorillonite / carboxylated multi-walled carbon nanotube composite material as well as a preparation method and application thereof, and belongs to the technical field of electrochemical sensors. According to the invention, chitosan intercalation modified montmorillonite and carboxylated multi-walled carbon nanotubes are adopted for synthesis, so that the material has excellent conductivity and catalytic activity. A non-enzymatic glucose electrochemical sensor constructed by using the composite material shows a wide linear range (0.001 mM to 5.78 mM), a low detection limit (1.09 mu M) and high sensitivity (3.89 mu A / cm <-2 >) at a working potential of-0.40 V, and can realize efficient selective detection of glucose molecules. The application of the carbon nanomaterial in non-invasive glucose detection is expanded, and a new approach with high sensitivity, low cost and non-invasive detection is provided for diabetics.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electrochemical sensors, and particularly relates to a preparation method of a chitosan intercalation modified montmorillonite / carboxylated multi-walled carbon nanotube composite material and application of the chitosan intercalation modified montmorillonite / carboxylated multi-walled carbon nanotube composite material prepared by the method to glucose detection as electrode material. BACKGROUND

[0002] Diabetes is a common chronic metabolic disease, and timely and accurate blood glucose monitoring is crucial for diabetes management. However, the current commonly used blood glucose detection methods mostly rely on invasive operations, which have problems such as poor patient experience and high risk of infection. Therefore, it is of great significance to develop a convenient, non-invasive and high-sensitivity glucose detection method.

[0003] In recent years, electrochemical sensors have become an important tool for non-invasive blood glucose detection due to their high sensitivity, simple operation and low cost. Electrochemical sensors are mainly divided into two categories: enzyme-based sensors and non-enzyme-based sensors. The former has high specificity and sensitivity, but its application is limited due to the sensitivity of enzyme molecules to environmental conditions and the inherent instability. Non-enzyme type glucose electrochemical sensors are widely concerned due to their good stability, convenient operation and low cost, but their detection sensitivity and selectivity still need to be further improved. Therefore, researchers try to use new composite materials to optimize their performance. For example, the combination of non-noble metal nanomaterials with carbon materials, conductive polymers and other conductive nanomaterials can promote effective synergistic effects between different materials, thereby improving the conductivity and catalytic activity of non-noble metal nanomaterials, and ultimately improving the overall performance of non-enzyme glucose sensors.

[0004] Sodium montmorillonite (Na-MMT) is widely used in the field of electrochemistry due to its unique two-dimensional layered structure and excellent ion exchange performance. Researchers such as Ghosh have built a sodium montmorillonite coating layer on the surface of tin oxide-coated glass plates, glassy carbon electrodes and platinum electrodes, and for the first time, they have preliminarily explored the charge and mass transport mechanism in the clay coating layer by cyclic voltammetry. However, its intrinsic conductivity is insufficient and needs to be improved through organic intercalation modification. For example, Roxana-Mihaela Apetrei and other researchers prepared octadecyl dimethyl ammonium chloride (DDAC) modified montmorillonite, and used the composite material to build a current type enzyme glucose biosensor electrode, which confirmed that the modified montmorillonite can promote the directional arrangement of enzyme molecules, thereby enhancing and maintaining the function of the sensor. Although the modified montmorillonite material and its composite material exhibit good electrochemical performance, it is still difficult to fully meet the practical application requirements of the sensor, and its properties, structure and performance still need to be further optimized.

[0005] As a natural organic polysaccharide, carboxymethylated chitosan (CS) has good biocompatibility and functionalization potential, and is suitable for the modification of sodium-based montmorillonite. For example, Cihan Topcu et al. studied the cation exchange mechanism, and inserted the protonated chitosan molecules into the interlayer of montmorillonite in the form of a single layer, and the prepared composite material was successfully applied to the electroactive component of a polyvinyl chloride (PVC) membrane potential sensor, and the direct and high-selectivity determination of hydrogen phosphate ions was realized. Carboxylated multi-walled carbon nanotubes (MWCNTs-COOH) have excellent conductivity, and by intercalating and modifying montmorillonite (CS-MMT) with chitosan, the overall sensing performance can be significantly improved, and efficient detection of glucose molecules can be realized. SUMMARY

[0006] Therefore, in order to solve the technical problems of the existing non-enzyme glucose electrochemical sensor, such as insufficient sensitivity and selectivity, the present application provides a chitosan intercalated modified montmorillonite / carboxylated multi-walled carbon nanotube composite material and a preparation method thereof, and application of the composite material as an electrode material for glucose detection. The chitosan intercalated modified montmorillonite is combined with carboxylated multi-walled carbon nanotubes to form a composite material, which not only has good conductivity, but also can effectively improve the performance of non-enzyme glucose sensors, and provides a new type of high-sensitivity glucose electrochemical sensor.

[0007] In order to achieve the above-mentioned purpose, the present application provides the following technical scheme:

[0008] In a first aspect, the present application provides a preparation method of a chitosan intercalated modified montmorillonite / carboxylated multi-walled carbon nanotube composite material, which is synthesized by combining chitosan intercalated modified montmorillonite with carboxylated multi-walled carbon nanotubes.

[0009] Preferably, the chitosan intercalated modified montmorillonite and the carboxylated multi-walled carbon nanotubes are synthesized by a hydrothermal method.

[0010] Preferably, the hydrothermal method is as follows:

[0011] The chitosan intercalated modified montmorillonite sample with an intercalation ratio of 4:1 is used as a base material, mixed with the carboxylated multi-walled carbon nanotubes obtained by pretreatment, and a hydrothermal method is used to react at 160℃ for 4h. After reaction cooling, the sample is filtered and washed, and then freeze-dried for 12h to obtain the chitosan intercalated modified montmorillonite / carboxylated multi-walled carbon nanotube composite material.

[0012] Preferably, the preparation method of the chitosan intercalated modified montmorillonite is as follows:

[0013] The sodium-based montmorillonite is used as a base, and the carboxymethylated chitosan is used as a modifier. The mass ratio of glucosamine in the carboxymethylated chitosan to the cation exchange capacity in the sodium-based montmorillonite is controlled to be 0.1:1 to 5:1.

[0014] Preferably, the mass ratio of cation exchange capacity is 4:1.

[0015] Preferably, the preparation method of chitosan intercalation modified montmorillonite is as follows:

[0016] A 2% sodium montmorillonite suspension was prepared, and a carboxylated modified chitosan solution was prepared and the pH was adjusted to 4.9. The mixture of sodium montmorillonite suspension and carboxylated modified chitosan solution was magnetically stirred at 60°C for 24 h, centrifuged and washed to remove acetate, and dried at 60°C for 12 h to obtain the intercalation product chitosan-intercalated modified montmorillonite.

[0017] Preferably, the preparation method of carboxylated multi-walled carbon nanotubes is as follows:

[0018] Multi-walled carbon nanotubes were dispersed in an acidic solution for reaction. After the reaction was completed and cooled to room temperature, the solution was filtered and washed until it was neutral. Then, it was rapidly frozen and lyophilized to obtain carboxylated multi-walled carbon nanotubes.

[0019] Preferably, the acid solution is a mixed solution of nitric acid and concentrated sulfuric acid, with a volume ratio of nitric acid to concentrated sulfuric acid of 3:1.

[0020] Secondly, the present invention provides a chitosan-intercalated modified montmorillonite / carboxylated multi-walled carbon nanotube composite material, which is prepared by the above-described preparation method.

[0021] Thirdly, the present invention also provides the above-mentioned chitosan intercalated modified montmorillonite / carboxylated multi-walled carbon nanotube composite material as an electrode material for glucose detection.

[0022] This invention provides a chitosan-intercalated modified montmorillonite / carboxylated multi-walled carbon nanotube composite material, its preparation method, and its application as an electrode material for glucose detection. The composite material, formed by chitosan-intercalated modified montmorillonite and carboxylated multi-walled carbon nanotubes, not only possesses good electrical conductivity but also effectively synergistically enhances the performance of non-enzymatic glucose sensors, providing a novel high-sensitivity glucose electrochemical sensor. Compared to existing technologies, it has the following beneficial effects:

[0023] (1) Significant synergistic effect of materials: By combining carboxylated chitosan (CS) intercalated with modified montmorillonite (MMT) and carboxylated multi-walled carbon nanotubes (MWCNTs-COOH), a synergistic effect of "inorganic layered structure-organic conductive network" is achieved. The biocompatibility and adsorption capacity of CS provide binding sites for glucose, while the high conductivity of MWCNTs-COOH accelerates electron transfer. The two work synergistically to enhance catalytic activity (sensitivity reaches 3.89 μA·mM). -1 ·cm -2 ).

[0024] The preparation process is precise and controllable: it adopts a two-step method of "magnetic heating and stirring intercalation + hydrothermal composite".

[0025] During the intercalation stage, the mass ratio of CS to Na-MMT (optimal 4:1) and pH value (4.9) are controlled to achieve the ordered arrangement of CS between MMT layers (interlayer spacing up to 2.50 nm), thereby enhancing the stability of the material.

[0026] Hydrothermal reaction (160℃, 4h) promotes the exfoliation of MMT layered structure and uniform dispersion of MWCNTs-COOH, forming a multi-scale rough surface, increasing specific surface area and optimizing interfacial reactivity.

[0027] Excellent detection performance and applicable scenarios:

[0028] Outstanding electrochemical performance: wide linear range (0.001mM-5.78mM), low detection limit (1.09μM), and strong anti-interference ability (no response to uric acid, dopamine, etc.);

[0029] Non-invasive application: Suitable for saliva glucose testing, overcoming the problems of poor user experience and high risk of infection associated with traditional invasive testing, providing a low-cost and convenient solution for diabetes management. Attached Figure Description

[0030] Figure 1 The X-ray diffraction (XRD) patterns of CS-MMT samples (CS-MMT / 0.1:1, CS-MMT / 1:1, CS-MMT / 2:1, CS-MMT / 3:1, CS-MMT / 4:1, CS-MMT / 5:1) prepared under different intercalation ratios in Example 1 are shown.

[0031] Figure 2 The image shows a scanning electron microscope (SEM) image of CS-MMT / 4:1 prepared under the condition of CS to Na-MMT ratio of 4:1 in Example 1.

[0032] Figure 3 The images show the XRD patterns of the CS-MM / 4:1, MWCNTs-COOH, MMT / MWCNTs-COOH and CS-MM / MWCNTs-COOH composite materials prepared in Example 1.

[0033] Figure 4 The image shows a SEM image of the CS-MMT / MWCNTs-COOH prepared in Example 1.

[0034] Figure 5 The electrochemical performance test results are for the CS-MMT / MWCNTs-COOH / GCE electrode prepared in Test Example 1. Where a represents the electrode prepared with 5 mM [Fe(CN)6]. 3- / 4- Cyclic voltammetry (CV) curves were obtained from KCl solution. b shows the electrochemical impedance spectroscopy (EIS) results for the GCE, MWCNTs-COOH / GCE, MMT / MWCNTs-COOH / GCE, and CS-MMT / MWCNTs-COOH / GCE electrodes. c shows the CV tests performed in NaOH with or without glucose. d shows the linear sweep voltammetry curves.

[0035] Figure 6 The kinetic test results are shown for the CS-MMT / MWCNTs-COOH / GCE electrode prepared in Test Example 1. In this figure, a represents the CV response test graphs of CS-MMT / MWCNTs-COOH / GCE at different scan rates (10-100 mV / s). b represents the peak current (IC). p ) and the square root of the scan rate (v 1 / 2 The linear relationship between CS-MMT / MWCNTs-COOH / GCE is shown in c, which represents the CV response test plots for different glucose concentrations (1-8 mM) at a scan rate of 50 mV / s. -1 d is the peak current (I p ) and glucose concentration (C glucose The fitted calibration curve.

[0036] Figure 7 Performance tests of the CS-MMT / MWCNTs-COOH / GCE electrode prepared in Example 1 were conducted under different applied voltages. Specifically, a) shows the amperometric response of CS-MMT / MWCNTs-COOH / GCE to successive additions of glucose in 0.1M NaOH solution at different potentials (-0.30 to -0.45 V). b) shows the corresponding linear calibration curve. c) shows the sensor sensitivity at different potentials.

[0037] Figure 8 This section evaluates the sensing performance of the CS-MMT / MWCNTs-COOH / GCE electrode prepared in Test Example 1 under optimal conditions. In the figures, a shows the amperometric measurement curve of CS-MMT / MWCNTs-COOH / GCE at -0.40V as glucose is gradually added. b shows the amperometric measurement curve at low glucose concentration. c shows the oxidation current (I) versus glucose concentration (C). glucose The variation between ) is shown in d. d represents the glucose detection anti-interference performance test when 0.05 times the interfering agent and 100 μM glucose are added. Detailed Implementation

[0038] To facilitate a better understanding of the present invention, the following examples are provided to further illustrate the invention. These examples fall within the scope of protection of the present invention, but do not limit the scope of protection of the present invention.

[0039] Example 1

[0040] Different ratios of CS-MMT intercalation materials were prepared to obtain the optimal sample CS-MMT / 4:1. The specific steps are as follows: Na-MMT was weighed and prepared into a 2% clay suspension; six portions of CS (CS with glucosamine content MW = 161 g mol) were weighed. -1 The ratios of CS to Na-MMT were adjusted to 0.1:1, 1:1, 2:1, 3:1, 4:1, and 5:1. CS was dissolved in a 2% clay suspension to form mixed solutions, and the pH of the mixed solutions was adjusted to 4.9. The mixtures were then stirred at 60°C for 24 hours. After the reaction, the reaction products were centrifuged and washed until free of acetate. The precipitates obtained after drying at 60°C for 12 hours were designated as CS-MMT / 0.1:1, CS-MMT / 1:1, CS-MMT / 2:1, CS-MMT / 3:1, CS-MMT / 4:1, and CS-MMT / 5:1. CS-MMT / 4:1 was ultimately selected as the optimal sample for subsequent experiments.

[0041] MWCNTs-COOH was prepared by an acid pretreatment method. 1.0 g of MWCNTs was dispersed in a mixed solution containing 60 mL of concentrated HNO3 and 20 mL of concentrated H2SO4, and the mixture was stirred at 80 °C for 3 h. After the reaction was completed and cooled to room temperature, the resulting product was filtered, washed several times with ultrapure water until the filtrate was neutral, and then rapidly frozen and lyophilized in liquid nitrogen to obtain MWCNTs-COOH.

[0042] A novel CS-MMT / MWCNTs-COOH composite material was prepared by combining CS-MMT with MWCNTs-COOH via a hydrothermal method. The obtained CS-MMT and MWCNTs-COOH were mixed and dispersed in a solution. The mixture was then transferred to a stainless steel autoclave and reacted at 160℃ for 4 h. After the reaction was completed and cooled to room temperature, the mixture was filtered, washed, and freeze-dried for 12 h to obtain a black powder, which was the CS-MMT / MWCNTs-COOH electrode material. The obtained CS-MMT / MWCNTs-COOH composite material was used as a sensing material, and its detection performance for glucose molecules was verified at an operating potential of -0.40 V.

[0043] Comparative Example

[0044] Sensor type: MEMS-integrated PI flexible glucose enzyme sensor, which is widely used in existing technologies. This is taken as an example: (Research on the fabrication of a patterned flexible glucose sensor based on a platinum electrode MEMS platform).

[0045] Table 1. Performance comparison of the present invention and comparative sensor.

[0046]

[0047] This invention overcomes the performance limitations of existing MEMS flexible enzyme sensors that rely on biological enzymes through the design of a novel CS-MMT / MWCNTs-COOH composite material and an enzyme-free detection mechanism.

[0048] In terms of core detection indicators, it outperforms the comparative model in performance tests such as linear range and detection limit, especially solving the key issue of narrow detection range of enzyme sensors. In terms of practical performance, the enzyme-free design brings long-term stability, wide temperature range adaptability and anti-interference ability, making it more suitable for the detection needs of complex clinical samples (such as serum). In terms of material cost, it avoids the use of expensive glucose oxidase, and the glassy carbon electrode preparation process (drop coating method) is simpler than MEMS photolithography-sputtering process, reducing the cost of large-scale production by about 60%.

[0049] In summary, this invention is significantly superior to existing technologies in terms of detection performance, practical value, and cost control, and its technological advancements have clear innovativeness and clinical application value.

[0050] Test Example 1

[0051] 2.0 mg of catalyst was dispersed in 1 mL of isopropanol / water mixture (3:1 v / v), and then 30 μL of 5 wt% Nafion was added. The mixture was sonicated for 80 min to obtain a uniform black ink. 4 μL of the catalyst ink was then drop-coated onto the surface of a pretreated glassy carbon electrode (GCE) and air-dried to form a uniform catalyst film. All electrochemical experiments were performed at room temperature in 0.1 M NaOH aqueous solution (pH = 13). Cyclic voltammetry (CV) measurements were performed in the potential range of -0.6 to 0.2 V. Linear sweep voltammetry (LSV) measurements were performed in the potential range of -0.8 to 1.2 V. Chronoamperometry was performed with the operating potential fixed at -0.4 V. The catalyst was then placed in a solution containing 5 mM [Fe(CN)6]. 3- / 4- Electrochemical impedance spectroscopy (EIS) was recorded in a frequency range of 50 mV at an optimal application potential of -0.4 V in a 0.1 M KCl solution containing the redox probe.

[0052] The following is a detailed description of Embodiment 1 and Test Example 1 of the present invention with reference to the accompanying drawings:

[0053] Figure 1X-ray diffraction (XRD) patterns of CS-MMT samples (CS-MMT / 0.1:1, CS-MMT / 1:1, CS-MMT / 2:1, CS-MMT / 3:1, CS-MMT / 4:1, CS-MMT / 5:1) prepared under different intercalation ratios in Example 1. With increasing CS content, the interlayer spacing of the (001) crystal plane gradually increases, indicating that CS molecules have successfully intercalated into the silicate layer of montmorillonite (MMT). Under mild acidic conditions, the multi-cationic properties exhibited by CS allow for intercalation into the MMT interlayers via cation exchange. When the mass ratio of CS to MMT is 1:1, the interlayer spacing expands to 2.05 nm, indicating that CS is intercalated in a parallel monolayer manner. With further increases in CS content, the interlayer spacing continues to expand. At a mass ratio of 4:1, the interlayer spacing reaches 2.50 nm, suggesting the formation of a bilayer structure composed of two layers of CS molecules and intercalated acetate ions. The second layer is connected to the first layer via hydrogen bonds, and the negative charge of MMT originates from the -NH3 in the first layer CS. + Group neutralization. These -NH3 groups... + The group can also serve as an ion exchange binding site for glucose.

[0054] Figure 2 The image shows a scanning electron microscope (SEM) image of CS-MMT / 4:1 prepared in Example 1 with a CS to Na-MMT ratio of 4:1. After CS modification, the CS-MMT surface exhibits an irregular cluster structure and a significant increase in roughness, indicating that the introduction of organic molecules disrupts the original layered structure of MMT.

[0055] Figure 3 The images show the XRD patterns of the CS-MM / 4:1, MWCNTs-COOH, MMT / MWCNTs-COOH, and CS-MM / MWCNTs-COOH composites prepared in Example 1. In CS-MMT / 4:1, the increased interlayer spacing and its well-defined bilayer structure are beneficial for glucose adsorption and sensing performance, and therefore it was chosen as the basis for subsequent composite material preparation. MWCNTs-COOH exhibits a sharp and broad diffraction peak at approximately 26.0°, corresponding to the (002) crystal plane of graphitic carbon, showing good graphitic order. In CS-MMT / MWCNTs-COOH, the (001) basal plane diffraction peak of MMT is significantly weakened or even disappears, indicating that after CS intercalation and the introduction of MWCNTs-COOH, the layered structure of MMT has been exfoliated, forming a disordered hybrid nanostructure.

[0056] Figure 4The image shows a SEM image of the CS-MMT / MWCNTs-COOH prepared in Example 1. This composite material exhibits a distinct multi-scale layered morphology, consisting of an inorganic layered structure and an organic fiber network. The surface structure is the most complex and rough, which is beneficial for increasing the specific surface area and enhancing interfacial reactivity.

[0057] Figure 5 The electrochemical performance test results are for the CS-MMT / MWCNTs-COOH / GCE electrode prepared in Test Example 1. Figure 5 a represents the presence of 5 mM [Fe(CN)6] 3- / 4- Cyclic voltammetry (CV) curves were performed in KCl solution. Bare GCE exhibited clear redox peaks. The current responses of Na-MMT / GCE and CS-MMT / GCE were limited, indicating poor conductivity. Although CS-MMT / MWCNTs-COOH was slightly lower than MWCNTs-COOH, it was superior to MMT / MWCNTs-COOH, suggesting that CS helps to construct an interfacial environment conducive to electron transfer, possibly due to its increased density of catalytically active sites. Figure 5 b shows the electrochemical impedance spectroscopy (EIS) results for the GCE, MWCNTs-COOH / GCE, MMT / MWCNTs-COOH / GCE, and CS-MMT / MWCNTs-COOH / GCE electrodes, with charge transfer resistances (Rct) of 60.53, 2.36, 26.45, and 13.90 Ω, respectively, indicating that the introduction of CS significantly improves the charge transport characteristics. Figure 5 c represents the CV test performed in NaOH with or without glucose. The results show that only CS-MMT / MWCNTs-COOH showed a significant increase in current after the addition of glucose, which is attributed to the adsorption capacity of CS and the electrocatalytic effect of MWCNTs-COOH. Figure 5 The LSV curve in d shows that CS-MMT / MWCNTs-COOH has the highest current density in the potential range of -0.6 to 1.0V, indicating that it has better conductivity and electroactive surface area.

[0058] Figure 6 The kinetic test results are for the CS-MMT / MWCNTs-COOH / GCE electrode prepared in Test Example 1. The CV response of the CS-MMT / MWCNTs-COOH / GCE electrode was tested at different scan rates (10-100 mV / s) in 0.1 M NaOH containing 8 mM glucose. Figure 6 a). As the scan rate increases, the anode peak (I) pa Positive shift, cathode peak (I) pc Negative shift. Peak current (I) p ) and the square root of the scan rate (v1 / 2 There is a good linear relationship between them. Figure 6 b) shows that glucose oxidation on the CS-MMT / MWCNTs-COOH / GCE electrode is a diffusion-controlled electrochemical process. This indicates that the rate-limiting step is the diffusion of glucose to the electrode surface, while the electron transfer process is relatively rapid. Figure 6 cd showed that the oxidation current gradually increased within the 1-8 mM glucose concentration range, with a good linear correlation (Rc). 2 =0.987), proving that the composite material has excellent electrocatalytic activity over a wide concentration range.

[0059] Figure 7 The performance of the CS-MMT / MWCNTs-COOH / GCE electrode prepared in Test Example 1 was tested under different applied voltages. The amperometric response of CS-MMT / MWCNTs-COOH / GCE was tested under continuously added 100 μM glucose conditions at applied potentials ranging from -0.45 to -0.30 V. Figure 7 In step a, the current response increases with increasing potential, reaching a peak at -0.40V, and then decreases slightly. Figure 7 c), therefore, -0.40V was selected as the optimal operating voltage. Figure 7 b).

[0060] Figure 8 The sensing performance of the CS-MMT / MWCNTs-COOH / GCE electrode prepared in Test Example 1 was evaluated under optimal conditions. Figure 8 In step a, glucose was continuously added to 0.1M NaOH, and the amperometric curve showed a saturation trend. Figure 8 In section b, the amperometric it curve at low glucose concentrations. The linear detection range is 1.0 μM–0.67 mM and 0.67–5.78 mM, and the corresponding calibration equation is:

[0061] I(μA)=3.925C_glucose-2.963(R 2 =0.991) and I(μA) =0.275C_glucose-0.703

[0062] (R 2 =0.993)( Figure 8 c). The sensor's sensitivity is 3.89 μA·mM. -1 ·cm -2 The detection limit is as low as 1.09 μM (S / N = 3). Figure 8 In d, common interfering substances such as UA, DA, AA and H2O2 have almost no effect on the response, and only glucose causes a significant change in current, indicating that it has good anti-interference ability.

[0063] The above description is merely a preferred embodiment of the present invention. However, the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention should be covered within the scope of protection of the present invention.

Claims

1. A method for preparing a chitosan-intercalated modified montmorillonite / carboxylated multi-walled carbon nanotube composite material, characterized in that, The synthesis was achieved by chitosan intercalation-modified montmorillonite and carboxylated multi-walled carbon nanotubes.

2. The method for preparing a chitosan-intercalated modified montmorillonite / carboxylated multi-walled carbon nanotube composite material according to claim 1, characterized in that, Chitosan-intercalated modified montmorillonite and carboxylated multi-walled carbon nanotubes were synthesized via a hydrothermal method.

3. The method for preparing a chitosan-intercalated modified montmorillonite / carboxylated multi-walled carbon nanotube composite material according to claim 2, characterized in that, The hydrothermal method specifically refers to: A chitosan-intercalated modified montmorillonite sample with an intercalation ratio of 4:1 was selected as the matrix material and mixed with pretreated carboxylated multi-walled carbon nanotubes. The mixture was reacted at 160℃ for 4 hours using a hydrothermal method. After the reaction was cooled, the mixture was filtered, washed, and freeze-dried for 12 hours to obtain a chitosan-intercalated modified montmorillonite / carboxylated multi-walled carbon nanotube composite material.

4. The method for preparing a chitosan-intercalated modified montmorillonite / carboxylated multi-walled carbon nanotube composite material according to claim 1, characterized in that, The preparation method of chitosan intercalation modified montmorillonite is as follows: Using sodium montmorillonite as the matrix and carboxylated chitosan as the modifier, the mass ratio of glucosamine in carboxylated chitosan to cation exchange capacity in sodium montmorillonite was controlled to be 0.1:1 to 5:

1.

5. The method for preparing a chitosan-intercalated modified montmorillonite / carboxylated multi-walled carbon nanotube composite material according to claim 4, characterized in that, The mass ratio of cation exchange capacity is 4:

1.

6. The method for preparing a chitosan-intercalated modified montmorillonite / carboxylated multi-walled carbon nanotube composite material according to claim 4, characterized in that, The specific preparation method of chitosan intercalation modified montmorillonite is as follows: A 2% sodium montmorillonite suspension was prepared, and a carboxylated modified chitosan solution was prepared and the pH was adjusted to 4.

9. The mixture of sodium montmorillonite suspension and carboxylated modified chitosan solution was magnetically stirred at 60°C for 24 h, centrifuged and washed to remove acetate, and dried at 60°C for 12 h to obtain the intercalation product chitosan-intercalated modified montmorillonite.

7. A method for preparing a chitosan-intercalated modified montmorillonite / carboxylated multi-walled carbon nanotube composite material according to any one of claims 1-6, characterized in that, The preparation method of carboxylated multi-walled carbon nanotubes is as follows: Multi-walled carbon nanotubes were dispersed in an acidic solution for reaction. After the reaction was completed and cooled to room temperature, the solution was filtered and washed until it was neutral. Then, it was rapidly frozen and lyophilized to obtain carboxylated multi-walled carbon nanotubes.

8. The method for preparing a chitosan-intercalated modified montmorillonite / carboxylated multi-walled carbon nanotube composite material according to claim 7, characterized in that, The acid solution is a mixture of nitric acid and concentrated sulfuric acid, with a volume ratio of 3:

1.

9. A chitosan-intercalated modified montmorillonite / carboxylated multi-walled carbon nanotube composite material, characterized in that, It is prepared by any one of the preparation methods according to claims 1-8.

10. The chitosan intercalated modified montmorillonite / carboxylated multi-walled carbon nanotube composite material of claim 9 is used as an electrode material for glucose detection.

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