Bacterial cellulose-based colorimetric sensing array as well as preparation method and application thereof
By using bacterial cellulose-based ZIF-67/BC composite materials in the colorimetric sensor, the problems of complex, high temperature and high cost in the ethylene gas detection methods in the prior art are solved, and the rapid and accurate detection of low-concentration ethylene gas is achieved, providing an efficient and portable gas detection solution.
Patent Information
- Application Number
- CN202510190150.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-20
- Publication Date
- 2025-05-30
AI Technical Summary
In the prior art, ethylene gas detection means usually require high temperature operations, complex operating procedures and are costly, making it difficult to achieve fast, portable and low-cost detection. Traditional colorimetric sensors have problems of adsorption instability and difficulty in identification in low-concentration gas detection.
Using a bacterial cellulose-based colorimetric sensing array, the performance of the colorimetric sensor is improved by combining ZIF-67 materials with high specific surface area and multi-active sites with BC as substrates. The array is prepared by ultrasonic treatment and magnetic stirring, and combined with a combination of colorimetric sensors of different colorimetric reactions to achieve rapid and accurate detection of ethylene gas.
The sensitivity and response speed of the colorimetric sensor to ethylene gas is significantly improved, and the rapid and accurate detection of trace ethylene gas is achieved. It overcomes the limitations of traditional colorimetric sensors in low-concentration gas detection, and provides an efficient, intuitive and convenient gas detection solution.
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Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of gas detection, and more particularly to a bacterial cellulose-based colorimetric sensing array, a preparation method thereof, and an application thereof. Background Art
[0002] Ethylene detection is of great significance in the fields of industry, agriculture, medicine, etc. Currently, most of the ethylene detections are based on electrical sensors, fluorescence sensors, and gas chromatography. However, these detection methods usually require a relatively high working temperature, are complex to operate, and have a high usage cost. Therefore, in the detection of ethylene gas, there is still an urgent need to find a fast, portable, and low-cost detection method.
[0003] Colorimetric sensors based on discoloring dyes for analyzing target substances through color changes have unique advantages in the long-term monitoring of gas components and concentrations due to their simple operation, low cost, intuitive result reflection, and high portability, and have great development potential. However, the discoloring dyes of traditional colorimetric sensors are relatively single, making it difficult to achieve specific recognition of trace gases and having poor color discrimination, which limits their development and application. To solve this problem, constructing a colorimetric sensing array based on a colorimetric sensor is an effective strategy to improve its specific recognition and color discrimination. The colorimetric sensing array is composed of an array of points formed by arranging multiple colorimetric sensors with different discoloration reactions. After the analyte adsorbs to the dyes at each array point, it will cause changes in the chemical or physical microenvironment at each sensitive point, resulting in color changes. Different analytes will cause different color changes, thus showing a strongly distinguishable color array distribution. Therefore, the composition of the analyte can be intuitively interpreted qualitatively and even quantitatively.
[0004] In the existing visual colorimetric sensing arrays, the target gas molecules are often adsorbed on the surface of the dye and directly respond to the dye. However, the dye has a weak adsorption to the gas, resulting in problems such as unstable adsorption and inability to collect and store the target gas. When the concentration of the target gas is low, the colorimetric sensing array is often difficult to identify.
[0005] Therefore, according to the application requirements of ethylene gas detection, developing a visual colorimetric sensing array with strong and sensitive color change response, high selectivity, and convenient use for special gases at room temperature is an urgent problem to be solved by those skilled in the art. Summary of the Invention
[0006] In view of this, to solve the above problems, the present invention provides a bacterial cellulose-based colorimetric sensing array, its preparation method and application. By compounding ZIF-67 material with high specific surface area and multiple active sites with BC as the substrate, the performance of the colorimetric sensor is effectively improved. This method is not only simple to operate and low in cost, but also improves the response speed and sensitivity of colorimetric sensing to ethylene gas, providing a new solution for gas detection technology.
[0007] To achieve the above object, the present invention adopts the following technical solutions:
[0008] First, the present invention provides a preparation method of a bacterial cellulose-based colorimetric sensing array, which specifically includes the following steps:
[0009] S1, Mix palladium chloride solution with an indicator, perform ultrasonic treatment, and then stir magnetically to obtain a PdCl 2 -indicator mixed solution;
[0010] S2, Immerse the ZIF-67 / BC composite material in the PdCl 2 -indicator mixed solution, and then take it out and dry it to obtain a colorimetric sensor;
[0011] S3, Combine multiple different colorimetric sensors to obtain a bacterial cellulose-based colorimetric sensing array.
[0012] The beneficial effects are as follows: By mixing the ZIF-67 / BC composite material with the dye, the performance of the colorimetric sensing array is effectively improved, the sensitivity of the colorimetric sensor to ethylene gas is enhanced, and the rapid and accurate detection of trace ethylene gas is realized.
[0013] At the same time, by combining multiple colorimetric sensors with different color change reactions into an array, each sensor reacts with ethylene gas molecules, resulting in color changes at each point of the array. This method significantly improves the specificity and sensitivity of ethylene gas detection. At the same time, the colorimetric array can achieve high selectivity and strong color change response at room temperature, overcoming the limitations of traditional colorimetric sensors in low-concentration gas detection, and providing an efficient, intuitive and convenient solution for gas detection.
[0014] In step S1, the concentration of the palladium chloride solution is 2-7 mg / mL; the volume ratio of the palladium chloride solution to the indicator is 1:3-9.
[0015] The indicator is methyl red indicator (MR), bromocresol green indicator (BG), thymol blue indicator (BB), methyl red and bromocresol green mixed indicator (MR+BG).
[0016] The methyl red indicator is 0.2 - 1.0 g / L; the bromocresol green indicator is 0.2 - 1.0 g / L; the thymol blue indicator is 0.1 - 0.5 g / L; the methyl red and bromocresol green mixed indicator is obtained by mixing the methyl red indicator and the bromocresol green indicator at a volume ratio of 1:2 - 5.
[0017] In step S1, the time for ultrasonic treatment is 10 - 30 min; the time for magnetic stirring is 4 - 6 h.
[0018] In step S2, the soaking time is 2 - 6 h; the drying is vacuum drying, the temperature is 60 °C, and the time is 6 - 12 h.
[0019] The preparation process of the ZIF-67 / BC composite material in step S2 is as follows:
[0020] S21, rinse the bacterial cellulose with a thickness of 3 - 10 mm in water for 24 h; then soak it in a 1 wt% sodium hydroxide solution at a temperature of 70 °C for 24 h; after soaking, wash it with water until neutral; then soak it in deionized water, change the water every 8 h, and change the water three times to obtain pretreated bacterial cellulose, and soak it in deionized water for standby.
[0021] S22, soak the pretreated bacterial cellulose in a methanol solution of 0.02 - 0.05 mol / L cobalt nitrate hexahydrate, stir for 1 - 3 h, and then perform ultrasonic treatment for 0.5 - 1 h to obtain a uniformly distributed BC-Co 2+ system.
[0022] S23, slowly drop a methanol solution of 0.1 - 0.3 mol / L 2-methylimidazole into the BC-Co 2+ system in S22, stir for 1 - 3 h, and then perform ultrasonic treatment for 0.5 - 1 h to obtain a mixed system.
[0023] S24, place the mixed system in S23 in a reaction kettle, react at a temperature of 70 - 120 °C for 12 - 36 h, after the reaction is completed, wash with methanol and deionized water to obtain the ZIF-67 / BC composite material.
[0024] Its beneficial effect lies in that by using bacterial cellulose (BC) as a flexible sensing substrate and combining the gas adsorption performance of metal-organic frameworks (MOFs), the performance of the colorimetric sensing array can be significantly improved.
[0025] Metal-organic framework (MOF) materials have received extensive attention due to their three-dimensional periodic porous structure and ultra-high specific surface area. The active adsorption sites in the pores of MOFs can effectively concentrate gases, which can be used as a gas adsorption layer, providing efficient adsorption and storage functions for the colorimetric sensing array, significantly improving the deficiency of dyes in adsorbing gases, and thus enhancing the detection sensitivity. Among them, ZIF-67 has the characteristics of high specific surface area and multiple active sites.
[0026] Bacterial cellulose (BC) has good flexibility and biocompatibility, which can meet the basic requirements of the substrate in gas detection, including: not reacting with the color-changing dye, the dye can be evenly dispersed, providing a white background, and having a high specific surface area which is beneficial to the adsorption and diffusion of the analyte, etc. BC also has a unique nanofiber network structure, high mechanical strength, high specific surface area and good processing performance, and can be in-situ grown and compounded with MOF powder to enhance the specific surface area and gas adsorption capacity of the substrate. At the same time, as a substrate, bacterial cellulose has the characteristics of good mechanical properties, being cheap and easily available, high yield, good biocompatibility, strong degradability, and being green and environmentally friendly, solving the problem that the high yield of bacterial cellulose cannot be applied with high quality.
[0027] The molar ratio of 2-methylimidazole and Co 2+ described in step S23 is 7-9:1.
[0028] The multiple different colorimetric sensors described in step S3 are 1-4.
[0029] In addition, the present invention also provides a bacterial cellulose-based colorimetric sensing array prepared by the method as described above.
[0030] In addition, the present invention also provides the application of the above-mentioned bacterial cellulose-based colorimetric sensing array in the detection of ethylene gas.
[0031] It can be seen from the above technical solutions that compared with the prior art, the present invention discloses a bacterial cellulose-based colorimetric sensing array, its preparation method and application, and its beneficial effects are as follows:
[0032] 1. By using a simple in-situ growth method to combine ZIF-67 with BC, the requirements of complex equipment or multiple steps are avoided. This method is green and environmentally friendly and meets the requirements of sustainable development. In addition, it solves the problem that the high yield of bacterial cellulose cannot be applied with high quality, which is beneficial to its popularization and application in the field of colorimetric sensing.
[0033] 2. By compounding ZIF-67 with high specific surface area and BC, the gas adsorption capacity of the sensor is significantly enhanced, the sensitivity and detection range of the colorimetric sensor are improved, and it performs more accurately especially in the detection of low-concentration ethylene gas.
[0034] 3. The colorimetric sensor of the invention has a compact structure, is easy to operate and has low cost. It has high stability and excellent response performance in practical applications. Its process flow has strong universality and is suitable for large-scale promotion in industrial production. Brief Description of the Drawings
[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.
[0036] Figure 1 Process flow chart of the present invention.
[0037] Figure 2 Performance comparison between BC-based and ZIF-67 / BC-based colorimetric sensing arrays
[0038] Figure 3 Electron micrographs of ZIF-67 and ZIF-67 / BC composites.
[0039] Figure 4 Physical diagram of the colorimetric sensor for detecting the ripeness of bananas.
[0040] Figure 5 RGB difference and Euclidean distance change diagram of the colorimetric sensor for detecting the ripeness of bananas. Detailed Description of the Invention
[0041] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.
[0042] Figure 1 The process flow chart of the present invention is as follows, and the specific preparation examples are as follows:
[0043] Example 1
[0044] Preparation of ZIF-67 / BC
[0045] 1. Rinse bacterial cellulose with a thickness of 3 mm in water for 24 h; then soak it in a 1 wt% sodium hydroxide solution at a temperature of 70 °C for 24 h; after soaking, wash it with water until neutral; then soak it in deionized water and change the water every 8 h. After changing the water three times, the pretreated bacterial cellulose is obtained and immersed in deionized water for standby.
[0046] 2. Immerse the pretreated bacterial cellulose in a methanol solution of 0.03 mol / L cobalt nitrate hexahydrate, stir for 2.5 h, and then perform ultrasonic treatment for 1 h to obtain BC-Co with uniform distribution. 2+ system.
[0047] 3. Slowly drip a methanol solution of 0.23 mol / L 2-methylimidazole into the BC-Co 2+ system, and require the molar ratio of 2-methylimidazole to Co 2+ to be 9:1, stir for 2 h, and then perform ultrasonic treatment for 0.5 h to obtain a mixed system.
[0048] 4. Place the mixed system in a reaction kettle, react at 70 °C for 12 h, after the reaction is completed, wash with methanol and deionized water to obtain the ZIF-67 / BC composite material.
[0049] Preparation of Bacterial Cellulose-based Colorimetric Sensing Array
[0050] 1. Respectively mix a palladium chloride solution with a concentration of 3 mg / mL with a methyl red indicator with a concentration of 0.5 g / L, a bromocresol green indicator with a concentration of 0.5 g / L, a thymol blue indicator with a concentration of 0.4 g / L, and a methyl red and bromocresol green mixed indicator obtained by a volume ratio of methyl red to bromocresol green of 1:2. Mix according to a volume ratio of palladium chloride to indicator of 1:3, perform ultrasonic treatment for 10 min, and then perform magnetic stirring for 4 h to obtain four PdCl 2 -indicator mixed solutions;
[0051] 2. Immerse the ZIF-67 / BC composite material in four PdCl 2 -indicator mixed solutions for 6 h, then take it out and dry it in vacuum at 60 °C for 12 h to obtain four colorimetric sensors;
[0052] 3. Combine the four colorimetric sensors to obtain a bacterial cellulose-based colorimetric sensing array.
[0053] Example 2
[0054] Preparation of ZIF-67 / BC
[0055] 1. Rinse the bacterial cellulose with a thickness of 5 mm in water for 24 h; then immerse it in a 1 wt% sodium hydroxide solution at a temperature of 70 °C for 24 h; after soaking, wash it with water until neutral; then immerse it in deionized water, change the water every 8 h, and change the water three times to obtain the pretreated bacterial cellulose, which is immersed in deionized water for standby.
[0056] 2. Immerse the pretreated bacterial cellulose in a methanol solution of 0.03 mol / L cobalt nitrate hexahydrate, stir for 2.5 h, and then ultrasonically treat for 1 h to obtain a BC-Co system with uniform distribution. 2+ system.
[0057] 3. Slowly drip a methanol solution of 0.18 mol / L 2-methylimidazole into the BC-Co 2+ system, requiring a molar ratio of 2-methylimidazole to Co 2+ of 7:1, stir for 2 h, and then ultrasonically treat for 1 h to obtain a mixed system.
[0058] 4. Place the mixed system in a reaction kettle, react at 90 °C for 24 h. After the reaction is completed, wash with methanol and deionized water to obtain the ZIF-67 / BC composite material.
[0059] Preparation of Bacterial Cellulose-Based Colorimetric Sensing Array
[0060] 1. Respectively mix a palladium chloride solution with a concentration of 3 mg / mL with a methyl red indicator with a concentration of 0.5 g / L, a bromocresol green indicator with a concentration of 0.5 g / L, a thymol blue indicator with a concentration of 0.4 g / L, and a methyl red and bromocresol green mixed indicator obtained by a volume ratio of methyl red to bromocresol green of 1:2. Mix according to a volume ratio of palladium chloride to the indicator of 1:3, ultrasonically treat for 10 min, and then magnetically stir for 4 h to obtain four PdCl 2 -indicator mixed solutions;
[0061] 2. Immerse the ZIF-67 / BC composite material in the four PdCl 2 -indicator mixed solutions for 6 h, then take it out and vacuum dry at 60 °C for 12 h to obtain four colorimetric sensors;
[0062] 3. Combine the four colorimetric sensors to obtain a bacterial cellulose-based colorimetric sensing array.
[0063] Example 3
[0064] Preparation of ZIF-67 / BC
[0065] 1. Rinse the bacterial cellulose with a thickness of 3 mm in water for 24 h; then immerse it in a 1 wt% sodium hydroxide solution at 70 °C for 24 h; after immersion, wash it with water until neutral; then immerse it in deionized water and change the water every 8 h. After changing the water three times, obtain the pretreated bacterial cellulose and immerse it in deionized water for standby.
[0066] 2. Immerse the pretreated bacterial cellulose in a methanol solution of 0.03 mol / L cobalt nitrate hexahydrate, stir for 2.5 h, and then ultrasonically treat for 1 h to obtain a BC-Co system with uniform distribution.2+ system
[0067] 3. Slowly drop the methanol solution of 0.23 mol / L 2-methylimidazole into the BC-Co 2+ system, requiring the molar ratio of 2-methylimidazole to Co 2+ to be 9:1, stir for 2 h, and then ultrasonically treat for 0.5 h to obtain a mixed system.
[0068] 4. Place the mixed system in a reaction kettle and react at 70 °C for 12 h. After the reaction is completed, wash with methanol and deionized water to obtain the ZIF-67 / BC composite material.
[0069] Preparation of Bacterial Cellulose-based Colorimetric Sensing Array
[0070] 1. Respectively mix the palladium chloride solution with a concentration of 5 mg / mL with methyl red indicator with a concentration of 0.25 g / L, bromocresol green indicator with a concentration of 0.25 g / L, thymol blue indicator with a concentration of 0.2 g / L, and a mixed indicator of methyl red and bromocresol green with a volume ratio of methyl red to bromocresol green of 1:3. Mix according to the volume ratio of palladium chloride to indicator of 1:9, ultrasonically treat for 10 min, and then magnetically stir for 4 h to obtain four PdCl 2 -indicator mixed solutions;
[0071] 2. Immerse the ZIF-67 / BC composite material in the four PdCl 2 -indicator mixed solutions for 6 h, then take it out and vacuum dry at 60 °C for 6 h to obtain four colorimetric sensors;
[0072] 3. Combine the four colorimetric sensors to obtain a bacterial cellulose-based colorimetric sensing array.
[0073] Comparative Example 1
[0074] Preparation of BC-based Colorimetric Sensing Array without Adding ZIF-67
[0075] Preparation of BC
[0076] 1. Rinse the bacterial cellulose with a thickness of 3 mm in water for 24 h; then immerse it in a 1 wt% sodium hydroxide solution at 70 °C for 24 h; after immersion, wash it with water until neutral; then immerse it in deionized water and change the water every 8 h. After changing the water three times, obtain the pretreated bacterial cellulose and immerse it in deionized water for standby.
[0077] Preparation of Bacterial Cellulose-based Colorimetric Sensing Array
[0078] 1. Prepare palladium chloride solutions with a concentration of 3 mg / mL and mix them with methyl red indicator with a concentration of 0.5 g / L, bromocresol green indicator with a concentration of 0.5 g / L, thymol blue indicator with a concentration of 0.4 g / L, and a methyl red and bromocresol green mixed indicator obtained by a volume ratio of 1:2 of methyl red to bromocresol green. Mix them according to a volume ratio of 1:3 of palladium chloride to the indicator, perform ultrasonic treatment for 10 min, and then magnetic stir for 4 h to obtain four PdCl 2 -indicator mixed solutions;
[0079] 2. Immerse BC materials in the four PdCl 2 -indicator mixed solutions for 6 h, then take them out and dry them in vacuum at 60 °C for 12 h to obtain four colorimetric sensors;
[0080] 3. Combine the four colorimetric sensors to obtain a bacterial cellulose-based colorimetric sensing array.
[0081] Performance comparison between BC-based and ZIF-67 / BC-based colorimetric sensing arrays
[0082] Figure 2 For the performance comparison between BC-based and ZIF-67 / BC-based colorimetric sensing arrays, it can be seen from the figure that under the condition of an ethylene concentration of 50 ppm, the change values of the Euclidean distances of the four color-changing dyes (methyl red MR, bromocresol green BG, thymol blue BB, and their combination MR+BG) of the ZIF-67 / BC-based colorimetric sensing array are all significantly greater than those of the BC-based array, indicating that the ZIF-67 / BC-based colorimetric sensing array shows better performance in ethylene color change response.
[0083] SEM characterization
[0084] Figure 3 For the electron micrographs of ZIF-67 and ZIF-67 / BC composites, it can be seen from the figure that the SEM image of ZIF-67 shows a regular dodecahedron shape. After it is compounded with bacterial cellulose (BC), it can be seen that a large number of regular dodecahedrons are tightly adhered to the cellulose network structure, indicating the successful preparation of the ZIF-67 / BC composite material.
[0085] Detection of banana ripeness by colorimetric sensors
[0086] Figure 4 For the physical map of the detection of banana ripeness by colorimetric sensors, since trace amounts of ethylene gas are released during banana ripening, unripe bananas are used as samples in the experiment. As time (1 day - 3 days) passes, obvious color changes occur in the colorimetric sensing array, proving that the colorimetric sensor has good responsiveness and sensitivity in the detection of low-concentration ethylene gas.
[0087] Figure 5It is a diagram showing the RGB differences and Euclidean distance changes in the detection of banana ripeness by a colorimetric sensor. After different discoloring dyes (such as methyl red MR, bromocresol green BG, thymol blue BB and their combination MR+BG) come into contact with ethylene gas, the color and Euclidean distance changes can be visually observed, further indicating that using discoloring dyes and composite materials to develop a colorimetric sensor is an effective method, especially suitable for the detection of low-concentration gases (such as ethylene).
[0088] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A method for preparing a bacterial cellulose-based colorimetric sensor array, characterized in that: The specific steps include: S1, mixing the palladium chloride solution and the indicator, ultrasonically treating, and then magnetically stirring to obtain a PdCl2-indicator mixed solution; S2, immersing the ZIF-67 / BC composite material in a PdCl2-indicator mixed solution, and then taking it out and drying it to obtain a colorimetric sensor; S3, combining a plurality of different colorimetric sensors to obtain a bacterial cellulose-based colorimetric sensor array.
2. The method for preparing a bacterial cellulose-based colorimetric sensor array according to claim 1, characterized in that: The concentration of the palladium chloride solution in step S1 is 2-7 mg / mL; the volume ratio of the palladium chloride solution to the indicator is 1:3-9. The indicator is a methyl red indicator, a bromocresol green indicator, a thymol blue indicator, or a mixed indicator of methyl red and bromocresol green.
3. The method for preparing a bacterial cellulose-based colorimetric sensor array according to claim 2, characterized in that: The methyl red indicator is 0.2-1.0 g / L; the bromocresol green indicator is 0.2-1.0 g / L; the thymol blue indicator is 0.1-0.5 g / L; the methyl red and bromocresol green mixed indicator is obtained by mixing the methyl red indicator and the bromocresol green indicator in a volume ratio of 1:2-5.
4. The method for preparing a bacterial cellulose-based colorimetric sensor array according to claim 1, characterized in that: The ultrasonic treatment time in step S1 is 10 to 30 minutes; the magnetic stirring time is 4 to 6 hours.
5. The method for preparing a bacterial cellulose-based colorimetric sensor array according to claim 1, characterized in that: The soaking time in step S2 is 2 to 6 hours; the drying is vacuum drying at a temperature of 60° C. for a time of 6 to 12 hours.
6. The method for preparing a bacterial cellulose-based colorimetric sensor array according to claim 1, characterized in that: The preparation process of the ZIF-67 / BC composite material in step S2 is as follows: S21, washing the bacterial cellulose with a thickness of 3 to 10 mm in water for 24 hours; then soaking it in a 1wt% sodium hydroxide solution at a temperature of 70°C for 24 hours; washing it with water until it is neutral after the soaking; then soaking it in deionized water, changing the water every 8 hours, and after changing the water three times, obtaining the pretreated bacterial cellulose, and soaking it in deionized water for standby use; S22, soaking the bacterial cellulose pretreated in S21 in a 0.02-0.05 mol / L methanol solution of cobalt nitrate hexahydrate, stirring for 1-3 h, and then ultrasonically treating for 0.5-1 h to obtain a uniformly distributed BC-Co 2+ system; S23, slowly add 0.1-0.3 mol / L 2-methylimidazole methanol solution to the BC-Co 2+ The system was stirred for 1 to 3 h, and then ultrasonically treated for 0.5 to 1 h to obtain a mixed system; S24, placing the mixed system in S23 in a reactor, reacting at a temperature of 70-120° C. for 12-36 hours, and after the reaction, washing with methanol and deionized water to obtain a ZIF-67 / BC composite material.
7. The method for preparing a bacterial cellulose-based colorimetric sensor array according to claim 6, characterized in that: In step S23, 2-methylimidazole and Co 2+ The molar ratio is 7 to 9:
1.
8. The method for preparing a bacterial cellulose-based colorimetric sensor array according to claim 1, characterized in that: The number of the multiple different colorimetric sensors in step S3 is 1 to 4.
9. A bacterial cellulose-based colorimetric sensor array prepared by the method according to any one of claims 1 to 8.
10. Use of a bacterial cellulose-based colorimetric sensor array prepared by the method according to any one of claims 1 to 8 or a bacterial cellulose-based colorimetric sensor array according to claim 9 in ethylene gas detection.