Core-sheath glucose sensing fiber and method of making the same
By using a core-sheath structure for preparing glucose sensing fibers, the colorimetric agent is encapsulated and protected by a sensitizer, which solves the problem of inaccurate colorimetric reactions and achieves highly sensitive and accurate glucose detection.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- WUHAN TEXTILE UNIV
- Filing Date
- 2026-02-11
- Publication Date
- 2026-06-05
AI Technical Summary
In existing glucose sensors, the accuracy of colorimetric reactions is not high, and they are easily affected by changes in enzyme activity and other chemical components, leading to false positive or false negative results.
A method for preparing core-sheath structure glucose sensing fibers was adopted. By preparing a dispersion of chromogenic functional material and a dispersion of composite enzyme, and mixing them with a polymer solution, a core layer and a sheath spinning solution were obtained. The spinning solution was obtained by coaxial wet spinning and freeze drying. The chromogenic agent was encapsulated by a sensitizer to protect it from direct contact with the external environment. The chromogenic functional material, as the core layer, avoids false negatives or false positives.
It improves the sensitivity and accuracy of colorimetric reactions, making it suitable for detecting glucose in bodily fluids and reducing false positive and false negative results.
Smart Images
Figure CN122147575A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of wearable colorimetric sensing technology, specifically to a core-sheath structure glucose sensing fiber and its preparation method. Background Technology
[0002] In the field of glucose sensing, enzyme colorimetry is one of the oldest and most mature detection methods for glucose. It couples the glucose oxidation process with a colorimetric reaction, converting a colorless substrate into a colored product, thereby indirectly quantifying glucose concentration through color changes or optical density.
[0003] However, biological samples (blood, urine, saliva) contain a variety of chemical components, creating a complex environment that can interfere with the accuracy of colorimetric reactions. The intensity of an enzyme-catalyzed colorimetric reaction directly depends on the activity of the enzyme. If enzyme activity decreases (due to changes in temperature or pH), the colorimetric reaction will become weaker. Furthermore, substances such as uric acid, bilirubin, and hemoglobin can react with the colorimetric reagent, producing false positives or false negatives, which limits its further biomedical and clinical applications. Summary of the Invention
[0004] In view of the technical problems existing in the background art, this application provides a core-sheath structure glucose sensing fiber and its preparation method, aiming to solve the problem of low accuracy of colorimetric reaction in existing glucose sensors.
[0005] In a first aspect, this application provides a method for preparing a core-sheath structured glucose sensing fiber, comprising the following steps: S1. Disperse the sensitizer and color developer in a solvent to obtain a dispersion of color-developing functional material; S2. Disperse the complex enzyme in a solvent to obtain a complex enzyme dispersion; S3. Prepare a polymer solution, and then mix it with the color-developing functional material dispersion and the composite enzyme dispersion respectively to obtain the core spinning solution and the skin spinning solution respectively; S4. The core spinning solution and the sheath spinning solution are coaxially wet-spun to obtain a core-sheath structure glucose sensing fiber precursor. S5. The core-sheath structure glucose sensing fiber precursor is freeze-dried to obtain the core-sheath structure glucose sensing fiber.
[0006] In the technical solution of this application embodiment, a chromogenic functional material dispersion and a composite enzyme dispersion are first prepared, and then mixed with a polymer solution to obtain a core spinning solution and a sheath spinning solution. These are then produced by coaxial wet spinning and freeze-drying to obtain a core-sheath structured glucose sensing fiber. By blending the chromogenic agent with a sensitizer, the hydrophobic core of the chromogenic agent is encapsulated by the sensitizer, and the entire outer surface of the composite is covered by the hydrophilic groups of the sensitizer. This increases the solubility of the chromogenic agent, thereby improving its dispersibility. Simultaneously, the reactive central groups on the surface of the chromogenic agent are protected, preventing direct contact with the external environment and thus avoiding false negatives or false positives. Furthermore, the chromogenic functional material as the core layer further avoids false negatives or false positives. The use of a specific polymer as the spinning substrate for both the sheath and core layers allows for rapid chromogenic reaction and improves sensitivity.
[0007] The prepared core-skin structure glucose sensing fiber can be used for glucose detection in biological fluids (blood, sweat, urine, tissue fluid).
[0008] In some embodiments, in step S1, the mass-volume concentration of the sensitizer is 0.1-20%, and the sensitizer is one or more of β-cyclodextrin, γ-cyclodextrin, hydroxypropyl-β-cyclodextrin, sulfobutyl ether-β-cyclodextrin, methylated-β-cyclodextrin, nonionic surfactant, anionic surfactant, cationic surfactant, and amphoteric surfactant.
[0009] In this embodiment, the sensitizer can coat the colorimetric agent, which not only solves the problem of the colorimetric agent being difficult to disperse evenly in the aqueous solvent, but also protects it from direct contact with the external environment, thus preventing false negatives or false positives.
[0010] In some embodiments, in step S1, the mass-volume concentration of the colorimetric agent is 0.1-20%, and the colorimetric agent is one or more of the following: 3,3',5,5'-tetramethylbenzidine, 3,3'-diaminobenzidine, 4-aminoantipyrine, phenol, resorcinol, N-ethyl-N-(2-hydroxy-3-sulfopropyl)-3-methylaniline, N,N-dimethylaniline, catechol, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, 3,3'-diethylthiacarbocyanine iodide, methylene blue, neutral red, rhodamine B, Prussian blue, tannic acid, and alizarin red S.
[0011] In this embodiment, the colorimetric agent can be directly catalyzed and oxidized by a complex enzyme or undergo a condensation reaction after catalysis to change color, thereby achieving the colorimetric effect.
[0012] In some embodiments, during steps S1 and S2, the stirring speed is 100-2000 rpm and the dispersion temperature is 0-60°C.
[0013] In this embodiment, by fully dispersing the sensitizer and the color developer in the solution under special stirring conditions, the sensitizer fully coats the color developer during the stirring process, solving the problem that the color developer is difficult to disperse evenly in the aqueous solvent, and also protecting it to prevent it from directly contacting the external environment, which could lead to false negatives or false positives.
[0014] In this embodiment, specific dispersion conditions are used to ensure that the complex enzyme is fully dissolved in the solvent without damaging the enzyme's performance.
[0015] In some embodiments, in step S2, the mass-volume concentration of the composite enzyme is 0.1-20%; the composite enzyme is one or more of the following: natural enzyme, metal oxide / hydroxide nanozyme, metal sulfide nanozyme, bimetallic / multi-metallic composite nanozyme, metal-organic framework nanozyme, and carbon-based nanozyme.
[0016] In this embodiment, the complex enzyme is used to catalyze the oxidation of the chromogenic agent to change color.
[0017] In some embodiments, in step S3, the mass-volume concentration of the polymer solution is 0.1-20%; the polymer in the polymer solution is one or more of mushroom fiber, sodium alginate, agarose, carrageenan, gelatin, chitosan, xanthan gum / guar gum, polyvinyl alcohol, polyethylene glycol derivatives, polyacrylamide, and cellulose derivatives; the solvent in the polymer solution is one or more of deionized water, PBS buffer solution, physiological saline, ethanol, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, chloromethane, and ionic liquids.
[0018] In this embodiment, specific polymers are selected as spinning substrates for the sheath and core layers, resulting in a uniform fiber structure that is not prone to delamination, good interfacial compatibility, and improved overall mechanical properties of the fiber.
[0019] In some embodiments, in step S3, the volume ratio of the polymer solution in the core spinning solution and the skin spinning solution is 1:(0.5~5).
[0020] In this embodiment, a fiber spinning solution with clear and uniform color development can be prepared by mixing the polymer solution with the color-developing functional material dispersion and the composite enzyme dispersion in a specific ratio.
[0021] In some embodiments, in step S1, the solvent is one or more of deionized water, PBS buffer solution, physiological saline, ethanol, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, chloromethane, dichloromethane, trichloromethane, and tetrachloromethane.
[0022] In this embodiment, the solvent can effectively dissolve the sensitizer and the color developer.
[0023] In some embodiments, in step S5, the freeze-drying temperature is -10°C to -80°C.
[0024] In this embodiment, freeze-drying creates a porous structure inside the fiber, increasing the fiber's specific surface area and raising the detection limit of the sensing fiber.
[0025] Secondly, this application provides a core-sheath structure glucose sensing fiber, which is prepared using the above-mentioned method for preparing core-sheath structure glucose sensing fibers.
[0026] In the technical solution of this application embodiment, the prepared core-sheath structure glucose sensing fiber has high reaction sensitivity and colorimetric reaction accuracy.
[0027] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description
[0028] To more clearly illustrate the technical solutions of this application, the accompanying drawings used in this application will be briefly described below. Obviously, the drawings described below are merely some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without any creative effort.
[0029] Figure 1 A 3D depth-of-field digital microscope image of the core-sheath structure glucose sensing fiber prepared in Example 1.
[0030] Figure 2 The image shows a SEM image of the core-sheath structure glucose sensing fiber prepared in Example 1; where a is a radial SEM image and b is a cross-sectional SEM image.
[0031] Figure 3 The images show the color change of the core-sheath structure glucose sensing fiber prepared in Example 1 in (a) artificial sweat solvent, (b) 0.5 mM glucose solution, (c) 1 mM glucose solution, and (d) 2 mM glucose solution.
[0032] Figure 4 The images show a comparison of (a) toughness and (b) breaking strength of the core-sheath structure glucose sensing fibers prepared in Examples 1-4.
[0033] Figure 5 The graph shows the sensing performance of the core-sheath structure glucose sensing fibers prepared in Examples 1-4.
[0034] Figure 6This is a diagram showing the color change effect of the core-sheath structure glucose sensing fiber prepared in Comparative Example 3 in a glucose solution. Detailed Implementation
[0035] The embodiments of the technical solution of this application are described in detail below. These embodiments are only used to more clearly illustrate the technical solution of this application, and are therefore merely examples and should not be used to limit the scope of protection of this application.
[0036] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.
[0037] To address the issue of low accuracy in colorimetric reactions in existing glucose sensors, this application provides a core-sheath structured glucose sensing fiber and its preparation method. First, a dispersion of a colorimetric functional material and a dispersion of a composite enzyme are prepared. These are then mixed with a polymer solution to obtain a core-layer spinning solution and a sheath-layer spinning solution. The resulting fiber is obtained through coaxial wet spinning and freeze-drying. By blending a colorimetric agent with a sensitizer, the hydrophobic core of the colorimetric agent is encapsulated by the sensitizer, and the entire outer surface of the composite is covered by the hydrophilic groups of the sensitizer. This increases the solubility of the colorimetric agent, thereby improving its dispersibility. Simultaneously, the reactive central groups on the surface of the colorimetric agent are protected, preventing direct contact with the external environment and thus avoiding false negatives or false positives. Furthermore, the colorimetric functional material as the core layer further avoids false negatives or false positives. The use of a specific polymer as the spinning substrate for both the sheath and core layers allows for rapid colorimetric reactions, improving sensitivity.
[0038] The prepared core-skin structure glucose sensing fiber can be used for glucose detection in biological fluids (blood, sweat, urine, tissue fluid).
[0039] On the one hand, this application provides a method for preparing a core-sheath structured glucose sensing fiber, comprising the following steps: S1. Disperse the sensitizer and color developer in a solvent to obtain a dispersion of color-developing functional material; S2. Disperse the complex enzyme in a solvent to obtain a complex enzyme dispersion; S3. Prepare a polymer solution, and then mix it with the color-developing functional material dispersion and the composite enzyme dispersion respectively to obtain the core spinning solution and the skin spinning solution respectively; S4. The core spinning solution and the sheath spinning solution are used to prepare a core-sheath structure glucose sensing fiber precursor by wet spinning technology. S5. The core-sheath structure glucose sensing fiber precursor is freeze-dried to obtain the core-sheath structure glucose sensing fiber.
[0040] In the technical solution of this application embodiment, a chromogenic functional material dispersion and a composite enzyme dispersion are first prepared, and then mixed with a polymer solution to obtain a core spinning solution and a sheath spinning solution. These are then produced by coaxial wet spinning and freeze-drying to obtain a core-sheath structure glucose sensing fiber. The chromogenic agent is blended with a sensitizer, and the hydrophobic core of the chromogenic agent is encapsulated by the sensitizer. The entire outer surface of the composite is covered by the hydrophilic groups of the sensitizer, which increases the solubility of the chromogenic agent, thereby improving its dispersibility. Simultaneously, the reactive central groups on the surface of the chromogenic agent are protected, preventing direct contact with the external environment and thus avoiding false negatives or false positives. The chromogenic functional material, as the core layer, further avoids false negatives or false positives. The sheath and core layers use a specific polymer as the spinning substrate, enabling rapid chromogenic reactions and improving sensitivity. The core-sheath structure glucose sensing fiber can be used for glucose detection in bodily fluids (blood, sweat, urine, tissue fluid).
[0041] Further, in some embodiments, in step S1, the mass-volume concentration of the sensitizer is 0.1-20%, and the sensitizer is one or more of β-cyclodextrin, γ-cyclodextrin, hydroxypropyl-β-cyclodextrin, sulfobutyl ether-β-cyclodextrin, methylated-β-cyclodextrin, nonionic surfactant, anionic surfactant, cationic surfactant, and amphoteric surfactant.
[0042] In the technical solution of this application embodiment, the sensitizer can coat the colorimetric agent, which not only solves the problem that the colorimetric agent is difficult to disperse evenly in the aqueous solvent, but also protects it from direct contact with the external environment, thus preventing false negatives or false positives.
[0043] Further, in some embodiments, in step S1, the mass-volume concentration of the colorimetric agent is 0.1-20%, and the colorimetric agent is one or more of 3,3',5,5'-tetramethylbenzidine, 3,3'-diaminobenzidine, 4-aminoantipyrine, phenol, resorcinol, N-ethyl-N-(2-hydroxy-3-sulfopropyl)-3-methylaniline, N,N-dimethylaniline, catechol, 2,2'-azidobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, 3,3'-diethylthiacarbocyanine iodide, methylene blue, neutral red, rhodamine B, Prussian blue, tannic acid, and alizarin red S.
[0044] In the technical solution of this application embodiment, the color developer can be directly catalyzed by the complex enzyme for oxidation or undergo a condensation reaction after catalysis to change color, thereby achieving the color development effect.
[0045] Furthermore, in some embodiments, in step S1, the stirring speed for dispersion is 100~2000 rpm, and the dispersion temperature is 0~60℃.
[0046] In the technical solution of this application embodiment, by fully dispersing the sensitizer and the color developer in the solution under special stirring conditions, the sensitizer fully coats the color developer during the stirring process, which solves the problem that the color developer is difficult to disperse evenly in the aqueous solvent, and also protects it to prevent it from directly contacting the external environment, thus preventing false negatives or false positives.
[0047] Furthermore, in some embodiments, in step S2, the mass-volume concentration of the composite enzyme is 0.1-20%; the composite enzyme is one or more of the following: natural enzyme, metal oxide / hydroxide nanozyme, metal sulfide nanozyme, bimetallic / multi-metallic composite nanozyme, metal-organic framework nanozyme, and carbon-based nanozyme.
[0048] In the technical solution of this application embodiment, the complex enzyme is used to catalyze the oxidation of the chromogenic agent to change color.
[0049] Further, in some embodiments, in step S3, the mass-volume concentration of the polymer solution is 0.1-20%; the polymer in the polymer solution is one or more of mushroom fiber, sodium alginate, agarose, carrageenan, gelatin, chitosan, xanthan gum / guar gum, polyvinyl alcohol, polyethylene glycol derivatives, polyacrylamide, and cellulose derivatives; the solvent in the polymer solution is one or more of deionized water, PBS buffer solution, physiological saline, ethanol, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, chloromethane, and ionic liquids. In the technical solution of this application embodiment, specific polymers are selected as spinning substrates for the skin layer and core layer, which makes the fiber structure uniform, not easy to delaminate, has good interfacial compatibility, and improves the overall mechanical properties of the fiber.
[0050] Furthermore, in some embodiments, in step S4, the volume ratio of the polymer solution in the core spinning solution and the skin spinning solution is 1:(0.5~5).
[0051] In the technical solution of this application embodiment, a fiber spinning solution with clear and uniform color development can be prepared by mixing the polymer solution with the color-developing functional material dispersion and the composite enzyme dispersion in a specific ratio.
[0052] Furthermore, in some embodiments, in step S3, the mixing speed is 100~2000 rpm, and the mixing time is 1~12h.
[0053] Furthermore, in some embodiments, in step S1, the solvent is one or more of deionized water, PBS buffer solution, physiological saline, ethanol, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, chloromethane, dichloromethane, trichloromethane, and tetrachloromethane.
[0054] In the technical solution of this application embodiment, the solvent can effectively dissolve the sensitizer and the color developer.
[0055] Furthermore, in some embodiments, in step S2, the solvent is one or more of deionized water, PBS buffer solution, physiological saline, ethanol, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, chloromethane, dichloromethane, trichloromethane, and tetrachloromethane.
[0056] Furthermore, in some embodiments, in step S2, the stirring speed for dispersion is 100~2000 rpm, and the dispersion temperature is 0~60℃.
[0057] In the technical solution of this application embodiment, the complex enzyme is fully dissolved in the solvent under specific dispersion conditions without damaging the enzyme's performance.
[0058] Further, in some embodiments, step S3, the wet spinning process specifically includes the following steps: extruding the core spinning solution and the sheath spinning solution from the needle into a coagulation bath to solidify and form a shape, placing them in an oven to dry, and winding them up to obtain a core-sheath structure glucose sensing fiber precursor; wherein, the extrusion rate ratio of the core spinning solution and the sheath spinning solution is 1:0.5~10, and the coagulation bath is a 1% calcium chloride solution.
[0059] Furthermore, in some embodiments, in step S4, the freeze-drying temperature is -10°C to -80°C.
[0060] In the technical solution of this application embodiment, freeze drying is used to create a porous structure inside the fiber, thereby increasing the specific surface area of the fiber and improving the detection limit of the sensing fiber.
[0061] Secondly, this application provides a core-sheath structure glucose sensing fiber, which is prepared using the above-mentioned method for preparing core-sheath structure glucose sensing fibers.
[0062] In the technical solution of this application embodiment, the glucose sensing fiber with a core-sheath structure has high reaction sensitivity and accurate colorimetric reaction.
[0063] The following are some specific embodiments. It should be noted that the embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application. Where specific techniques or conditions are not specified in the embodiments, they shall be performed in accordance with the techniques or conditions described in the literature in this field or according to the product instructions. Reagents or instruments whose manufacturers are not specified are all conventional products that can be obtained commercially.
[0064] Example 1 This embodiment provides a method for preparing a core-sheath structured glucose sensing fiber, which specifically includes the following steps: (1) Weigh 50 mg of β-cyclodextrin and 50 mg of 3,3',5,5'-tetramethylbenzidine, and stir thoroughly at 25°C and 200 rpm to dissolve them in 5 mL of PBS buffer solution to obtain a colorimetric functional material dispersion. (2) Weigh 25 mg of glucose oxidase and 12.5 mg of horseradish peroxidase, and dissolve them in 2 mL of PBS buffer solution at 25 °C and 200 rpm to obtain a composite enzyme dispersion. (3) Weigh 2g of sodium alginate into 18g of PBS buffer solution and stir thoroughly at 25℃ and 200rpm to dissolve it, so as to obtain a polymer solution with a mass concentration of 8%. Mix the polymer solution with the colorimetric functional material dispersion at a volume ratio of 1:2 and the polymer solution with the composite enzyme dispersion at a volume ratio of 1:4. Stir thoroughly at 200rpm for 10h to obtain the core spinning solution and the skin spinning solution respectively. The volume ratio of polymer solution in the core spinning solution and the skin spinning solution is 1:2. (4) The obtained core spinning solution and sheath spinning solution are placed on a spinning device. The core spinning solution and sheath spinning solution are extruded from the needle into a 1% calcium chloride solution coagulation bath at extrusion rates of 6 mL / h and 0.6 mL / h, respectively, by coaxial wet spinning technology. The solution is then dried in an oven and wound up to obtain a core-sheath structure glucose sensing fiber precursor. (5) The core-shell structure glucose sensing fiber precursor was freeze-dried at -10℃ to obtain the core-shell structure glucose sensing fiber.
[0065] A physical image of the core-sheath structure glucose sensing fiber prepared in this embodiment is shown below. Figure 1 As shown.
[0066] Depend on Figure 1 It can be seen that the obtained glucose sensing fiber has a distinct core-sheath structure.
[0067] SEM images of the radial and cross-sectional areas of the core-sheath structure glucose sensing fiber prepared in this embodiment are shown below. Figure 2As shown, the obtained glucose sensing fiber has a smooth surface, and the core layer is completely encapsulated in the skin layer, proving that the core-skin structure glucose sensing fiber was successfully prepared.
[0068] Figure 3 The images show the color change of the core-shell structured glucose sensing fiber in artificial sweat and glucose solutions of different concentrations. As can be seen, the color of the core layer of the glucose sensing fiber gradually deepens with increasing glucose solution concentration, indicating the excellent sensing performance of the glucose sensing fiber.
[0069] Examples 2-4 and Comparative Examples 1-2 Examples 2-4 and Comparative Examples 1-2 respectively provide a method for preparing a core-sheath structure glucose sensing fiber. The difference from Example 1 is that the volume ratio of the polymer solution in the core spinning solution and the sheath spinning solution is different, as shown in Table 1. The other steps are roughly the same as in Example 1, and will not be repeated here.
[0070] Table 1 Experiments show that core-sheath structured glucose sensing fibers can be successfully prepared in Examples 1-4.
[0071] The relevant mechanical properties of the core-sheath structure glucose sensing fibers prepared in Examples 1-4 are as follows: Figure 4 As shown, the sensing performance is as follows Figure 5 As shown.
[0072] Depend on Figure 4 , Figure 5 It can be seen that when the volume ratio of the core polymer to the sheath polymer is in the range of 1:(0.5~5), as the volume ratio of the sheath polymer to the core polymer increases, the fiber strain and toughness first increase and then decrease, and the sensing color development rate also first increases and then decreases, but overall it remains at a good level.
[0073] When the volume ratio of the core polymer to the sheath polymer is less than 1:5, the sheath is too thick, making it difficult for sweat to penetrate and reach the core, thus hindering the color development of the core polymer. This results in poor sensing performance of the core-sheath structure glucose sensing fiber. When the volume ratio of the core polymer to the sheath polymer is greater than 1:0.5, the sheath cannot completely encapsulate the core, leaving part of the core exposed to the air. This causes the color developer to oxidize and develop color, affecting the sensing accuracy of the core-sheath structure glucose sensing fiber.
[0074] Comparative Example 3 This comparative example provides a method for preparing a core-sheath structure glucose sensing fiber. The difference from Example 1 is that the sensitizer β-cyclodextrin was not added. The other steps are roughly the same as in Example 1, and will not be repeated here.
[0075] The color change pattern of the sensor fiber prepared in this comparative example in glucose solution is shown in the following figure. Figure 6 As shown.
[0076] Depend on Figure 6 It can be seen that the color developer was not evenly dispersed when no sensitizer (β-cyclodextrin) was added.
[0077] Comparative Example 4 This comparative example provides a method for preparing a core-sheath structured glucose sensing fiber. The difference from Example 1 is that the sheath spinning solution and the core spinning solution are exchanged. The other steps are roughly the same as in Example 1 and will not be repeated here.
[0078] Experiments show that when the spinning solution of the cortex and the spinning solution of the core are exchanged, the color developer is exposed to the air and oxidized by the air, affecting the accuracy of the sensing.
[0079] It should be noted that the sensitizer can be one or more of the following: β-cyclodextrin, γ-cyclodextrin, hydroxypropyl-β-cyclodextrin, sulfobutyl ether-β-cyclodextrin, methylated-β-cyclodextrin, nonionic surfactant, anionic surfactant, cationic surfactant, and amphoteric surfactant.
[0080] The colorimetric reagent can be one or more of the following: 3,3',5,5'-tetramethylbenzidine, 3,3'-diaminobenzidine, 4-aminoantipyrine, phenol, resorcinol, N-ethyl-N-(2-hydroxy-3-sulfopropyl)-3-methylaniline, N,N-dimethylaniline, catechol, 2,2'-azidobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, 3,3'-diethylthiacarbocyanine iodide, methylene blue, neutral red, rhodamine B, Prussian blue, tannic acid, and alizarin red S.
[0081] In summary, this application provides a core-sheath structure glucose sensing fiber and its preparation method. First, a chromogenic functional material dispersion and a composite enzyme dispersion are prepared, then mixed with a polymer solution to obtain a core spinning solution and a sheath spinning solution. These are then spun coaxially using a wet spinning method and freeze-dried to obtain the core-sheath structure glucose sensing fiber. By blending a chromogenic agent with a sensitizer, the hydrophobic core of the chromogenic agent is encapsulated by the sensitizer, and the entire outer surface of the composite is covered by the hydrophilic groups of the sensitizer. This increases the solubility of the chromogenic agent, thereby improving its dispersibility. Simultaneously, the reactive central groups on the surface of the chromogenic agent are protected, preventing direct contact with the external environment and thus avoiding false negatives or false positives. The chromogenic functional material, as the core layer, further avoids false negatives or false positives. The sheath and core layers use a specific polymer as the spinning substrate, enabling rapid chromogenic reactions and improving sensitivity. The core-sheath structure glucose sensing fiber can be used for glucose detection in bodily fluids (blood, sweat, urine, tissue fluid).
[0082] It should be noted that this application is not limited to the above-described embodiments. The above embodiments are merely examples, and any embodiments with the same structure and effect as the technical concept within the scope of this application are included in the technical scope of this application. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments, and other ways of constructing by combining some of the constituent elements of the embodiments, without departing from the spirit of this application, are also included in the scope of this application.
Claims
1. A method for preparing a core-sheath structured glucose-sensing fiber, characterized in that, Includes the following steps: S1. Disperse the sensitizer and color developer in a solvent to obtain a dispersion of color-developing functional material; S2. Disperse the complex enzyme in a solvent to obtain a complex enzyme dispersion; S3. Prepare a polymer solution, and then mix it with the color-developing functional material dispersion and the composite enzyme dispersion respectively to obtain the core spinning solution and the skin spinning solution respectively; S4. The core spinning solution and the sheath spinning solution are coaxially wet-spun to obtain a core-sheath structure glucose sensing fiber precursor. S5. The core-sheath structure glucose sensing fiber precursor is freeze-dried to obtain the core-sheath structure glucose sensing fiber.
2. The method for preparing the core-sheath structure glucose sensing fiber according to claim 1, characterized in that, In step S1, the mass-volume concentration of the sensitizer is 0.1-20%, and the sensitizer is one or more of the following: β-cyclodextrin, γ-cyclodextrin, hydroxypropyl-β-cyclodextrin, sulfobutyl ether-β-cyclodextrin, methylated-β-cyclodextrin, nonionic surfactant, anionic surfactant, cationic surfactant, and amphoteric surfactant.
3. The method for preparing the core-sheath structure glucose sensing fiber according to claim 1, characterized in that, In step S1, the mass-volume concentration of the colorimetric reagent is 0.1-20%, and the colorimetric reagent is one or more of the following: 3,3',5,5'-tetramethylbenzidine, 3,3'-diaminobenzidine, 4-aminoantipyrine, phenol, resorcinol, N-ethyl-N-(2-hydroxy-3-sulfopropyl)-3-methylaniline, N,N-dimethylaniline, catechol, 2,2'-azidobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, 3,3'-diethylthiacarbocyanine iodide, methylene blue, neutral red, rhodamine B, Prussian blue, tannic acid, and alizarin red S.
4. The method for preparing the core-sheath structure glucose sensing fiber according to claim 1, characterized in that, In steps S1 and S2, during the dispersion process, the stirring speed is 100~2000 rpm and the temperature is 0~60℃.
5. The method for preparing the core-sheath structure glucose sensing fiber according to claim 1, characterized in that, In step S2, the mass-volume concentration of the composite enzyme is 0.1-20%; the composite enzyme is one or more of the following: natural enzyme, metal oxide / hydroxide nanozyme, metal sulfide nanozyme, bimetallic / multi-metallic composite nanozyme, metal-organic framework nanozyme, and carbon-based nanozyme.
6. The method for preparing the core-sheath structure glucose sensing fiber according to claim 1, characterized in that, In step S3, the mass-volume concentration of the polymer solution is 0.1-20%; the polymer in the polymer solution is one or more of mushroom fiber, sodium alginate, agarose, carrageenan, gelatin, chitosan, xanthan gum / guar gum, polyvinyl alcohol, polyethylene glycol derivatives, polyacrylamide, and cellulose derivatives; the solvent in the polymer solution is one or more of deionized water, PBS buffer solution, physiological saline, ethanol, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, chloromethane, and ionic liquids.
7. The method for preparing the core-sheath structure glucose sensing fiber according to claim 1, characterized in that, In step S3, the volume ratio of the polymer solution in the core spinning solution and the skin spinning solution is 1:(0.5~5).
8. The method for preparing the core-sheath structure glucose sensing fiber according to claim 1, characterized in that, In step S1, the solvent is one or more of the following: deionized water, PBS buffer solution, physiological saline, ethanol, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, chloromethane, dichloromethane, trichloromethane, and tetrachloromethane.
9. The method for preparing the core-sheath structure glucose sensing fiber according to claim 1, characterized in that, In step S5, the freeze-drying temperature is -10℃ to -80℃.
10. A core-sheath structure glucose sensing fiber, characterized in that, The glucose sensing fiber with a core-shell structure as described in any one of claims 1 to 9 was prepared.