Covalent bond-induced gluten-pectin hydrogel and preparation method and application thereof

Abstract

The present application relates to a kind of covalent bond induced gluten-pectin hydrogel and its preparation method and application, the preparation method specifically is: after reducing treatment to gluten, obtain the reduced gluten solution;Again, with sulfhydryl pectin solution is fully mixed to be uniform;Then, dialysis is carried out in weak alkaline buffer solution, and gluten-pectin hydrogel is obtained.The preparation method of the present application is simple, the operation time is short, does not need oxidant, and the rheological property of the obtained hydrogel enhances pectin gel, and the responsiveness is enhanced.

Description

Technical Field

[0001] This invention belongs to the field of biomaterials technology, specifically relating to a covalently induced gluten-pectin hydrogel and its preparation method. Background Technology

[0002] Pectin is a complex and functionally diverse natural plant polysaccharide. It is a common soluble dietary fiber in plants and a major component of plant cell walls. Pectin is classified into high-methoxyl pectin and low-methoxyl pectin based on its degree of esterification. Pectin gels have a wide range of applications, but they also have some inherent drawbacks. For example, high-methoxyl pectin requires high-sugar and high-acid conditions to form a gel, which limits its application in neutral and alkaline environments. Furthermore, physically cross-linked pectin hydrogels exhibit low strength and weak responsiveness.

[0003] Thiol-modified polymers have attracted widespread attention due to their versatility. Because of their thiol groups, these polymers can form disulfide bonds with cysteine-rich proteins, thus achieving strong adhesion to many organisms. Furthermore, these thiol groups also facilitate the formation of stable three-dimensional hydrophilic networks within their own structures via disulfide crosslinking. High-methoxyl pectin can introduce free thiol groups by linking L-cysteine ​​through amide bonds in the presence of EDC / NHS.

[0004] Glutenin is a heterogeneous macromolecular polymer composed of polypeptide chains linked by intermolecular disulfide bonds. Because glutenin has a large number of disulfide bonds, reducing these bonds induces the formation of gluten-thiolized pectin hydrogels through covalent bonding, thereby improving the strength and responsiveness of the pectin gel. Summary of the Invention

[0005] The present invention aims to provide a method for preparing covalently induced glutenin-pectin hydrogel; wherein, glutenin is reduced to obtain a reduced glutenin solution; then it is thoroughly mixed with a thiolated pectin solution until homogeneous; and then dialyzed in a weakly alkaline buffer to obtain glutenin-pectin hydrogel.

[0006] Specifically, the preparation method includes: modifying pectin with thiol groups to obtain thiolized pectin; reducing glutenin to obtain glutenin with more free thiol groups; mixing the thiolized pectin and the reduced glutenin evenly; and under dialysis, the thiolized pectin and glutenin crosslink through disulfide bonds to form a hydrogel. The principle is as follows: Figure 1 As shown.

[0007] The preparation method of this invention is simple, has a short operation time, does not require an oxidant, and the resulting hydrogel enhances the compressibility of pectin gel and improves responsiveness.

[0008] The method for preparing the thiolized pectin is as follows:

[0009] Dissolve pectin powder in water to allow it to fully absorb water; then adjust the pH to 4-4.5, add EDC and NHS to make the final concentration 0.05M (mol / L); then add L-cysteine ​​and adjust the pH to 5-6 to carry out the reaction.

[0010] The mass ratio of L-cysteine ​​to pectin is 1 to 5:1.

[0011] Preferably, the reaction is adjusted in two steps: after adding L-cysteine, the pH is first adjusted to 5.0 and stirred in the dark for about 3 hours; then it is adjusted to 6.0 and stirred for about 30 minutes to complete the reaction.

[0012] After the reaction was complete, the mixture was dialyzed in the dark and then freeze-dried to obtain thiolated pectin.

[0013] The thiolized pectin is preferably prepared by the following method:

[0014] 1) Dissolve pectin powder in deionized water to obtain a 1% (w / v) pectin solution, and stir overnight to ensure full water absorption.

[0015] 2) Adjust the pH of the pectin solution to 4.5 with 1M NaOH, add EDC and NHS to make the final concentration 0.05M, and mix and stir for 15 minutes.

[0016] 3) Add L-cysteine ​​at a mass ratio of 1:1 to 5:1 to pectin, adjust the pH to 5.0, and stir for 3 hours in the dark.

[0017] 4) Adjust the pH to 6.0, stir for 30 min to complete the reaction, dialyze in the dark for 40 h, freeze dry to obtain thiolized pectin.

[0018] Preferably, the mass ratio of L-cysteine ​​to pectin is 3:1.

[0019] The ratio of free thiol groups in the reduced glutenin solution to the thiolized pectin solution is 9:1 to 4:6.

[0020] Preferably, when the ratio of free thiol groups in the reduced glutenin solution and the thiolated pectin solution is different, the resulting hydrogel will exhibit different performance states. Preferably, when the ratio of free thiol groups in the reduced glutenin solution to the thiolated pectin solution is 4-5:5-6, the hydrogel has a dense structure, strong mechanical properties, and excellent rheological properties; especially when the ratio is 4:6, the overall performance is the strongest.

[0021] Preferably, the concentration of the thiolized pectin solution is 6.0–90 mg / mL; in practical applications, the solution concentration is adjusted based on the thiol ratio.

[0022] The reduced gluten solution is prepared by the following method: gluten is reduced using any one of DTT, β-mercaptoethanol, Na2SO3 or NaHSO3.

[0023] Preferably, the concentration of the reducing agent is 0.05M to 0.5M.

[0024] The reduction treatment is carried out at a temperature of 40–60°C for 1–3 hours.

[0025] The buffer solution is PBS buffer with a pH of 7.0–8.0.

[0026] Preferably, the molecular weight of the dialysis bag is 10-100 kDa;

[0027] Preferably, the dialysis time is 40 min to 2 h, the dialysis is performed 1 to 2 times, and the dialysis temperature is 20 to 30 °C.

[0028] This invention provides a preferred embodiment in which the glutenin-pectin hydrogel is prepared by the following method:

[0029] 1) Dissolve gluten in a 0.05M to 0.5M reducing agent solution and reduce it for 1 to 3 hours at a temperature of 40 to 60°C to obtain a reduced gluten solution;

[0030] 2) Mix the reduced gluten solution and the thiolated pectin solution thoroughly until homogeneous; wherein the ratio of free thiol groups in the reduced gluten solution to the thiolated pectin solution is 4-5:5-6;

[0031] 3) Then, dialyze the solution in a buffer solution with a pH of 7.0–8.0 to obtain gluten-pectin hydrogel.

[0032] The present invention provides another preferred embodiment, wherein the glutenin-pectin hydrogel is prepared by the following method:

[0033] 1) Dissolve pectin powder in water to allow it to fully absorb water; then adjust the pH to 4-4.5, add EDC and NHS to make the final concentration 0.05M; then add L-cysteine, first adjust the pH to 5.0, stir in the dark for about 3 hours; then adjust to 6.0, stir for about 30 minutes to complete the reaction and obtain thiolated pectin.

[0034] The mass ratio of L-cysteine ​​to pectin is 3:1.

[0035] 2) Dissolve gluten in a 0.05M to 0.5M reducing agent solution and reduce it for 1 to 3 hours at a temperature of 40 to 60°C to obtain a reduced gluten solution;

[0036] 3) Prepare a solution of the thiolated pectin obtained in step 1) and mix it thoroughly with the reduced gluten solution until homogeneous; wherein the ratio of free thiol groups in the reduced gluten solution to that in the thiolated pectin solution is 4:6.

[0037] 4) Then dialyze the solution in a buffer solution with a pH of 7.0 to 8.0 to obtain gluten-pectin hydrogel.

[0038] Another object of the present invention is to provide a glutenin-pectin hydrogel prepared by any of the above preparation methods.

[0039] The glutenin-pectin hydrogel obtained by this invention is easy to store and convenient to use. In practical applications, the hydrogel needs to be dissociated. This dissociation is achieved by using a reducing agent to break disulfide bonds.

[0040] The reducing agent is selected from one of DTT, reduced glutathione, and β-mercaptoethanol.

[0041] Preferably, the concentration of the reducing agent is 50–100 mM.

[0042] A third objective of this invention is to provide the application of the above-mentioned gluten-pectin hydrogel in the preparation of drug release carriers and cell scaffolds.

[0043] This invention provides a method for preparing and dissociating covalently induced glutenin-pectin hydrogels. The method involves thiolation modification of pectin to introduce free thiol groups, while simultaneously reducing glutenin to expose free thiol groups. By adding a reduced glutenin solution to a thiolated pectin solution and dialysis to remove the reducing agent, the thiolated pectin molecules can crosslink with glutenin through disulfide bonds to form a hydrogel. The use of a reducing agent to disrupt the disulfide bonds in the hydrogel results in a hydrogel with reversible controllability, enabling the slow release of active substances. Compared to current pectin gels, this invention utilizes proteins and pectin prepared under mild conditions, expanding the application of pectin gels in neutral and alkaline conditions, and exhibiting good biocompatibility and responsiveness. Attached Figure Description

[0044] Figure 1 This is a schematic diagram illustrating the experimental principle for preparing glutenin-pectin hydrogel according to the present invention.

[0045] Figure 2The images show the detection results of the thiolated pectin prepared in Examples 1 to 5; where (A) is the free thiol group content of the thiolated pectin prepared in Examples 1 to 5; and (B) is the infrared spectrum of the thiolated pectin prepared in Example 1.

[0046] Figure 3 The frequency scan diagrams are of the gluten-pectin hydrogels prepared in Examples 6, 9-13.

[0047] Figure 4 The elastic modulus comparison diagrams of the gluten-pectin hydrogels prepared in Examples 6, 9-13 are shown (n=3).

[0048] Figure 5 This is a frequency scan comparison of the gluten-pectin hydrogels prepared in Example 6 and Example 8.

[0049] Figure 6 Comparison of the compression modulus of glutenin-pectin hydrogels prepared in Examples 6, 9-13 (n=3).

[0050] Figure 7 This is a comparison of the results of CCK-8 assays performed on GES-1 cells after incubation with the gluten-pectin hydrogel prepared in Example 13 for different time periods. (n=4) Detailed Implementation

[0051] The following examples are used to illustrate the present invention, but are not intended to limit the scope of the invention.

[0052] Example 1

[0053] This embodiment provides a method for preparing thiolized pectin, as detailed below:

[0054] 1) Dissolve pectin powder in deionized water to obtain a 1% (w / v) pectin solution, and stir overnight to ensure full water absorption.

[0055] 2) Adjust the pH of the pectin solution to 4.5 with 1M NaOH, add EDC and NHS to make the final concentration 0.05M, and mix and stir for 15 minutes.

[0056] 3) Add L-cysteine, adjust the pH to 5.0, and stir in the dark for 3 hours. The mass ratio of L-cysteine ​​to pectin is 5:1.

[0057] 4) Adjust the pH to 6.0, stir for 30 min to complete the reaction, dialyze in the dark for 40 h, freeze dry to obtain thiolated pectin; determine the thiol content in the thiolated pectin using the Ellman method; it is 545.60±11.67 μmol / g, and characterize the thiolated pectin using infrared spectroscopy.

[0058] Examples 2-5

[0059] This embodiment provides a method for preparing thiolated pectin, which differs from Example 1 only in the mass ratio of L-cysteine ​​to pectin.

[0060] The ratios are 1:1, 2:1, 3:1, and 4:1.

[0061] The hydrogels in Examples 6-13 below were prepared using thiolized pectin obtained in Example 1.

[0062] Example 6

[0063] This embodiment provides a method for preparing covalently induced glutenin-pectin hydrogel, as detailed below:

[0064] 1) Weigh 1g of gluten and dissolve it in 25mL of urea solution (8M urea, 0.2M SDS, 0.5M β-mercaptoethanol). Incubate in a water bath at 50℃ for 2 hours. After centrifugation, discard the precipitate.

[0065] The final reducing agent concentration (the concentration of reducing agent in the urea solution) is 0.05M; the reduction in reducing agent concentration here is to lay the foundation for the subsequent application of the hydrogel.

[0066] 2) Place the reduced gluten solution in a dialysis bag and dialyze it in 0.05M β-mercaptoethanol solution at room temperature for 24 hours with stirring. Centrifuge the dialyzed solution in a centrifuge tube to remove the precipitate and obtain the gluten solution.

[0067] 3) Dissolve the thiolated pectin in deionized water to prepare a thiolated pectin solution with a concentration of 26 mg / mL.

[0068] 4) Adjust the pH of the pectin solution to 7 with 1M NaOH, add 500μL of gluten solution, where the ratio of free thiol groups in the gluten solution to the thiolated pectin solution is 7:3, and stir evenly for a period of time. Dialyze in 50mM PBS buffer (pH 7.4) for 2 hours. After dialysis, place in a beaker or EP tube and wait for the gluten-pectin hydrogel to form.

[0069] Example 7

[0070] This embodiment provides a method for preparing covalently induced glutenin-pectin hydrogels.

[0071] The preparation method of gluten-pectin hydrogel in this embodiment is the same as that in Example 1, except that the pH of the 50mM PBS buffer is 8.0 in step (4).

[0072] Example 8

[0073] This embodiment provides a method for preparing covalently induced glutenin-pectin hydrogels.

[0074] The preparation method of gluten-pectin hydrogel in this embodiment is the same as that in Example 1, except that the dialysis time in step (4) is 40 min.

[0075] Example 9

[0076] This embodiment provides a method for preparing covalently induced glutenin-pectin hydrogels.

[0077] The preparation method of gluten-pectin hydrogel in this embodiment is the same as in Example 1, except that the concentration of thiolated pectin is 6 mg / mL in step (3) and the molar ratio of free thiol groups in gluten solution to thiolated pectin solution is 9:1.

[0078] Example 10

[0079] This embodiment provides a method for preparing covalently induced glutenin-pectin hydrogels.

[0080] The preparation method of gluten-pectin hydrogel in this embodiment is the same as that in Example 1, except that the concentration of thiolated pectin is 15 mg / mL in step (3) and the molar ratio of free thiol groups in gluten solution to thiolated pectin solution is 8:2.

[0081] Example 11

[0082] This embodiment provides a method for preparing covalently induced glutenin-pectin hydrogels.

[0083] The preparation method of gluten-pectin hydrogel in this embodiment is the same as that in Example 1, except that the concentration of thiolated pectin is 40 mg / mL in step (3) and the molar ratio of free thiol groups in gluten solution to thiolated pectin solution is 6:4.

[0084] Example 12

[0085] This embodiment provides a method for preparing covalently induced glutenin-pectin hydrogels.

[0086] The preparation method of gluten-pectin hydrogel in this embodiment is the same as in Example 1, except that the concentration of thiolated pectin is 60 mg / mL in step (3) and the molar ratio of free thiol groups in gluten solution to thiolated pectin solution is 5:5.

[0087] Example 13

[0088] This embodiment provides a method for preparing covalently induced glutenin-pectin hydrogels.

[0089] The preparation method of gluten-pectin hydrogel in this embodiment is the same as that in Example 1, except that the concentration of thiolated pectin is 91 mg / mL in step (3) and the molar ratio of free thiol groups in gluten solution to thiolated pectin solution is 4:6.

[0090] Example 14

[0091] This embodiment provides a method for the dissociation of covalently induced glutenin-pectin hydrogels.

[0092] The gluten-pectin hydrogel was prepared in Example 1. The prepared hydrogel was immersed in 100 mM GSH solution for 12 h at a temperature of 25 °C, and the gluten-pectin hydrogel dissociated.

[0093] Comparative Example 1

[0094] A method for preparing gluten-pectin hydrogel, the preparation method is the same as in Example 1, except that: in step (4), no dialysis is performed, and the gel is left to stand at 25°C for 12 hours.

[0095] Experimental Example 1

[0096] Table 1 shows the formation of gluten-pectin hydrogels in Examples 1-7 and Comparative Example 1.

[0097]

[0098]

[0099] Experimental Example 2

[0100] 1. Detect the thiol content in the thiolized pectin obtained in Examples 1-5.

[0101] 1.1 Ellman's Method

[0102] After adding 2 mL of DTNB solution (0.03%, 0.5 M, pH 8.0 PBS buffer), 0.2 mL of thiolated pectin aqueous solution (5.00 mg / mL) was mixed with 1.8 mL of PBS buffer (0.5 M, pH 8.0). The mixture was allowed to stand in the dark at room temperature for 2 hours. Then, the mixture was centrifuged at 10000 rpm for 5 min, and the absorbance of the resulting supernatant was recorded at 412 nm using a visible spectrophotometer. The thiol content (μmol / g) was calculated using a standard curve of cysteine ​​standards.

[0103] 1.2 Fourier Transform Infrared Spectroscopy

[0104] Fourier transform infrared spectroscopy: Thiol-modified pectin freeze-dried powder, pectin powder, and dried potassium bromide were mixed and ground under an infrared lamp, then pressed into transparent and uniform thin sheets using a tablet press. These sheets were placed in the instrument and spectroscopy was performed at 4000–400 cm⁻¹.-1 Scanning within the area. 32 scans were performed, with a resolution of 4 cm. -1 .

[0105] 1.3 Experimental Results

[0106] Experimental results are as follows Figure 2 As shown, thiolated pectin was prepared at L-cysteine ​​to pectin mass ratios ranging from 1:1 to 5:1. After freeze-drying, the free thiol content was determined using the Ellman method. Comparison revealed that when the L-cysteine ​​to thiolated pectin mass ratio was 3:1, as... Figure 2 As shown in Figure A, the free thiol content was the highest, at 545.60 ± 11.67 μmol / g. Fourier transform infrared spectroscopy characterization revealed that, compared to pectin, thiolized pectin retained all the typical peaks of natural pectin, but with different intensities.

[0107] In addition, such as Figure 2 In the B-wavelength analysis, three newly derived peaks or shoulders were observed in the thiolated pectin. Among them, the peak at 2560 cm⁻¹... -1 The peak value is the stretching vibration peak of the thiol group, while the other two peak values ​​are at 1527 cm⁻¹. -1 and 1331cm -1 The NH stretching and CN amide III bands of the amide group were observed separately. The presence of the SH stretching and NH stretching vibrations confirms that the cysteine ​​moiety was successfully bound to the pectin via the amide bond.

[0108] 2. Mechanical characterization of the glutenin-pectin hydrogels prepared in Examples 6, 9-13.

[0109] 2.1 Rheological Analysis

[0110] The viscoelasticity of the hydrogel was determined using a rotational rheometer. At 25°C, the sample was dynamically oscillated using the rotational rheometer in the range of 0.01–10 Hz, yielding curves showing the storage modulus and loss modulus of the sample as a function of angular frequency.

[0111] 2.2 Texture Analysis

[0112] A cylindrical hydrogel sample (20 mm in diameter × 10 mm in height) was prepared. Then, the texture analyzer was switched to compression measurement mode, and the test was performed at a speed of 30 mm / min under 40% strain.

[0113] 2.3 Experimental Results

[0114] Dynamic scanning can detect the trends of storage modulus (G') and loss modulus (G”) of hydrogels with angular frequency, thereby further evaluating the physical properties of hydrogels.

[0115] The modulus of the hydrogels in Examples 6, 9, 10, 11, 12, and 13 are as follows: Figures 3-4 As shown.

[0116] Under 1% strain, the storage modulus of the six gels in the 0.01-10Hz range was consistently greater than the loss modulus, indicating that the gluten-pectin hydrogel possesses the characteristics of a solid gel. With increasing frequency, G' remained stable, while G” initially decreased and then increased, remaining essentially stable, indicating that the hydrogel exhibits a certain degree of stability.

[0117] From Figure 3 It was found that as the content of thiolated pectin increased, the G' of the hydrogel gradually increased, the hydrogel structure became more compact, and the hydrogel mechanical properties were stronger. The hydrogel achieved the best rheological properties when the ratio of gluten to thiolated pectin thiol groups was 4:6 (hydrogel prepared in Example 13).

[0118] The frequency scans of the glutenin-pectin hydrogels prepared in Examples 6 and 8 were compared; for example... Figure 5 As shown, the gel formation time of hydrogels with a dialysis time of 2 hours is shorter than that of hydrogels with a dialysis time of 40 minutes; the gels have larger G' and G" values ​​in the frequency scan, indicating more stable gel properties. This demonstrates that the longer the dialysis time, the faster the gel formation time.

[0119] The compressive modulus of the hydrogel was analyzed using a texture analyzer. The experimental results are as follows: Figure 6 As shown, with the increase of thiolated pectin content, the compressive modulus of glutenin-pectin hydrogel gradually increases, and the structure becomes more compact. However, for thiolated pectin gels, excessively high concentrations will make the gel brittle, reduce the compressive modulus, and exhibit lower resilience. Figure 6 It can be seen that the addition of gluten improves the compressibility of the gel. When the ratio of gluten to thiolated pectin thiol is 4:6, the compressibility is optimal. Subsequent experiments using this gel show that Example 13 has the best compressibility.

[0120] 3. Testing the biocompatibility of gluten-pectin hydrogel in Example 13

[0121] 3.1 Cytotoxicity test

[0122] Cytotoxicity was detected using the CCK-8 assay. 100 μL of a 1×10⁻⁶ ppm solution was used. 5GES-1 cell suspensions of [number] cells / mL were placed in 96-well plates and incubated at 37°C for 24 h in a 5% CO2 incubator. Subsequently, 10 μL of glutenin-pectin gel was added to each well, and the plates were incubated for 12 and 24 h, respectively. After incubation, 10 μL of CCK-8 solution was added to each well, and the plates were incubated at 37°C for 2 h in a 5% CO2 incubator. Cell viability was determined by measuring absorbance at 450 nm using a microplate reader.

[0123] 3.2 Experimental Results

[0124] GES-1 cells were selected for cytotoxicity assays. After incubating GES-1 cells with gluten-pectin hydrogels for different times, the number of viable cells was detected using a CCK-8 assay kit. Figure 7 As shown, the gluten-pectin hydrogel did not produce cytotoxicity and effectively promoted cell proliferation after 24 hours of incubation with cells.

[0125] Although the present invention has been described in detail above with general descriptions, specific embodiments, and experiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A method for preparing a covalently induced glutenin-pectin hydrogel, characterized in that, After reducing gluten, a reduced gluten solution was obtained; then it was thoroughly mixed with a thiolated pectin solution until homogeneous; then, it was dialyzed in a weakly alkaline buffer to obtain a gluten-pectin hydrogel. The reduced gluten solution was prepared by the following method: gluten was reduced using any one of the reducing agents, DTT, β-mercaptoethanol, Na2SO3 or NaHSO3. The thiolized pectin was prepared by the following method: Dissolve pectin powder in water to allow it to fully absorb water; then adjust the pH to 4-4.5, add EDC and NHS to make the final concentration 0.05 M; then add L-cysteine ​​and adjust the pH to 5-6 to carry out the reaction.

2. The preparation method according to claim 1, characterized in that, The ratio of free thiol groups in the reduced glutenin solution to the thiolized pectin solution is 9:1 to 4:

6.

3. The preparation method according to claim 1, characterized in that, The ratio of free thiol groups in the reduced glutenin solution to the thiolized pectin solution is 4~5:5~6.

4. The preparation method according to any one of claims 1 to 3, characterized in that, The concentration of the reducing agent is 0.05 M to 0.5 M.

5. The preparation method according to claim 4, characterized in that, The reduction treatment is performed at a temperature of 40-60°C for 1-3 hours.

6. The preparation method according to any one of claims 1 to 3, characterized in that, The mass ratio of L-cysteine ​​to pectin is 1~5:

1.

7. The preparation method according to any one of claims 1 to 3, characterized in that, The reaction was controlled in two steps: after adding L-cysteine, the pH was first adjusted to 5.0 and stirred in the dark for about 3 hours; then it was adjusted to 6.0 and stirred for about 30 minutes to complete the reaction.

8. The preparation method according to claim 1, characterized in that, The buffer solution is PBS buffer with a pH of 7.0 to 8.

0.

9. The preparation method according to claim 1 or 8, characterized in that, The molecular weight of the dialysis bag used in the dialysis is 10~100 KD.

10. The preparation method according to claim 9, characterized in that, The dialysis time is 40 min to 2 h, and the dialysis is performed 1 to 2 times. The dialysis temperature is 20 to 30℃.

11. The preparation method according to claim 1, characterized in that, Includes the following steps: 1) Dissolve gluten in a 0.05 M to 0.5 M reducing agent solution and reduce it for 1 to 3 h at a temperature of 40 to 60 °C to obtain a reduced gluten solution; 2) Mix the reduced gluten solution and the thiolated pectin solution thoroughly until homogeneous; wherein the ratio of free thiol groups in the reduced gluten solution to the thiolated pectin solution is 4~5:5~6; 3) Then dialyze the solution in a buffer solution with a pH of 7.0~8.0 to obtain gluten-pectin hydrogel.

12. The preparation method according to claim 11, characterized in that, The specific preparation method is as follows: 1) Dissolve pectin powder in water to allow it to fully absorb water; then adjust the pH to 4-4.5, add EDC and NHS to make the final concentration 0.05 M; then add L-cysteine, first adjust the pH to 5.0, stir in the dark for about 3 hours; then adjust to 6.0, stir for about 30 minutes to complete the reaction, dialyze and freeze dry to obtain thiolated pectin; The mass ratio of L-cysteine ​​to pectin is 3:

1. 2) Dissolve gluten in a 0.05 M to 0.5 M reducing agent solution and reduce it for 1 to 3 h at a temperature of 40 to 60 °C to obtain a reduced gluten solution; 3) Prepare a solution of the thiolated pectin obtained in step 1), and mix it thoroughly with the reduced gluten solution until homogeneous; wherein the ratio of free thiol groups in the reduced gluten solution to that in the thiolated pectin solution is 4:6; 4) Then, dialyze the solution in a buffer with a pH of 7.0~8.0 to obtain gluten-pectin hydrogel.

13. The gluten-pectin hydrogel prepared by the preparation method according to any one of claims 1 to 12.

14. The application of the gluten-pectin hydrogel according to claim 13 in the preparation of drug release carriers and cell scaffolds.

15. The application according to claim 14, characterized in that, Application of dissociated glutenin-pectin hydrogel in the preparation of drug delivery carriers and cell scaffolds; wherein, the glutenin-pectin hydrogel achieves gel dissociation by breaking disulfide bonds with a reducing agent.

16. The application according to claim 15, characterized in that, The reducing agent is selected from one of DTT, reduced glutathione, and β-mercaptoethanol.

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