CN117624744A - Novel hydrogel and preparation method and application thereof - Google Patents

Abstract

The invention discloses a novel hydrogel and a preparation method and application thereof, wherein the prepared synthesized hydrogel is a novel hydrogel with good adhesiveness, injectability, broad-spectrum antibacterial property and oxidation resistance, and the prepared gallic acid modified chitosan and the dynamic chemical crosslinking hydrogel of the aldehyde hyaluronic acid can load exosomes of stem cell sources in the hydrogel, so that the effect of slow release of the exosomes can be achieved; secondly, the hydrogel has superior pore structure and molecular characteristics, is favorable for cell migration and tissue regeneration, provides a new choice for enhancing cell functions, repairing wound surfaces and treating skin tissue remodeling, and simultaneously expands new possibilities for application of stem cell exosomes in tissue engineering.

Description

A new type of hydrogel and its preparation method and application

Technical field

The invention belongs to the technical field of hydrogel materials, and specifically relates to a new type of hydrogel and its preparation method and application.

Background technique

Hydrogel is a special polymer material with water-absorbing properties. It can absorb and retain large amounts of moisture, forming a gel-like or gel-like state when in contact with water or other liquids. It is a rapidly developing functional polymer material that is widely used in biomedicine, enzyme activity control, molecular separation and other fields. It especially plays a very important role in surgery, burns, chronic ulcers, and wound repair, because the wound surface Repair treatment has always been a major clinical challenge. Due to the limited effect of traditional treatment methods, pressure repair after suturing, skin flap transplantation, etc. can only be used for superficial wound repair, and there are certain limitations for deep wound repair. In order to meet clinical needs, new hydrogels that overcome these shortcomings will need to be developed to achieve better wound treatment effects.

In order to prevent wounds or wound infections, antibacterial dressings are indispensable; at the same time, adhesion is also very important for hydrogels. Good adhesion allows them to adhere to the surface of the patient's affected area and can be used for a long time. treatment; however, most hydrogels will oxidize and lose their original properties after being used for a long time, so there is still room for improvement in these aspects.

Contents of the invention

In order to solve the above technical problems, the present invention provides a new type of hydrogel and its preparation method and application, which can load stem cell-derived exosomes on gallic acid-modified chitosan (hereinafter referred to as CSGA) and aldehyde Dynamic chemical cross-linking hydrogel of hyaluronic acid (hereinafter referred to as HA-ALD) was used to prepare a multifunctional hydrogel dressing that can sustainably release exosomes. The hydrogel has a variety of excellent properties, including good With its mechanical properties, tissue adhesion, spectrum antibacterial activity and antioxidant capacity, it accelerates epidermal regeneration and dermal structure reconstruction. This multi-functional hydrogel dressing, hereinafter referred to as ECGH, provides a new option for wound repair treatment; at the same time It also expands new possibilities for the application of stem cell exosomes in tissue engineering.

In order to achieve the above technical effects, on the one hand, the present invention discloses a new type of hydrogel, including: a first component and a second component; the first component includes gallic acid-modified chitosan or its derivatives ; The second component includes aldehyde hyaluronic acid or its derivatives; the first component and the second component are chemically dynamically cross-linked, and the ratio of reaction cross-linking is between 1:1 and 1:2. between;

On the other hand, the present invention provides a method for preparing a novel hydrogel, which includes the following steps:

S1: Use 4-8M HCl to adjust the pH of chitosan to 4-6 and then dissolve it in deionized water to form a 1.5wt% chitosan solution;

S2: Heat the chitosan solution obtained in S1 to 50-70°C in a water bath, and use _N2 to deoxidize for 10 minutes, then add gallic acid to the chitosan solution for reaction;

S3: Dissolve EDC and NHS in a mixture of ethanol and water in a ratio of 1:1 to 1:2, and then add the mixture dropwise to the mixed solution obtained in S2, and keep the pH at 4-6 in a N2 environment Reaction 12-24h;

S4: Dialyze the solution obtained in S3 in acidified deionized water containing NaCl for 4-7 days to inhibit the oxidation of the catechol group; then freeze and dry to obtain gallic acid-modified chitosan CS-GA;

S5: Dissolve a certain amount of hyaluronic acid in deionized water, stir evenly, add a certain amount of sodium periodate and react for 3-5 hours under dark conditions;

S6: Add ethylene glycol to the solution reacted in S5 to terminate the reaction, and continue stirring for 2-4 hours; after halving, dialyze the resulting solution in deionized water for 4 days, and finally freeze and dry to obtain aldehyde. Hyaluronic acid HA-ALD;

S7: Add a certain amount of hUCMSCs-Exo to 4% HA-ALD, and mix evenly with ultrasonic; then, shake and mix the above solution with 3wt% CS-GA solution in a volume ratio of 1:1 to 1:2. ; After mixing evenly, an injectable Exo@CsGA-HA hydrogel is obtained.

In the third aspect, the present invention provides the application of a new type of hydrogel. Exosomes derived from stem cells are loaded into the hydrogel. Since CSGAHA can form a pore structure, the exosomes can be loaded into the hydrogel, and the preparation can be sustained-released. Multifunctional hydrogel dressing based on exosomes.

The beneficial effects of the present invention are:

The present invention prepares and synthesizes a new type of hydrogel with good adhesion, injectability, broad-spectrum antibacterial properties and antioxidant properties, and uses the prepared gallic acid-modified chitosan and aldehylated hyaluronic acid to The dynamic chemical cross-linking hydrogel of acid can load stem cell-derived exosomes in it, and can achieve the effect of slow release of exosomes; secondly, the hydrogel of the present invention has superior pore structure and molecular characteristics, and has It helps cell migration and tissue regeneration, provides new options for enhancing cell function and wound repair treatment, and also expands new possibilities for the application of stem cell exosomes in tissue engineering.

Description of drawings

In order to explain the technical solutions of the embodiments of the present invention more clearly, the drawings required for describing the embodiments will be briefly introduced below.

Figure 1 is a morphology diagram of the hydrogel after freeze-drying;

Figure 2 is a schematic diagram of the wave number and absorption intensity obtained after measurement by FTIR method;

Figure 3 is a diagram of measured zeta potential.

Detailed ways

Example 1

In this embodiment, a method for preparing a novel hydrogel is provided, which includes the following steps:

S1: Use 4-8M HCl to adjust the pH of chitosan to 4-6 and then dissolve it in deionized water to form a 1.5wt% chitosan solution;

S2: Heat the chitosan solution obtained in S1 to 50-70°C in a water bath, and use _N2 to deoxidize for 10 minutes, then add gallic acid to the chitosan solution for reaction; the mass of gallic acid added is 100-150mg between;

S3: Dissolve EDC and NHS in a mixture of ethanol and water with a ratio of 1:1 to 1:2, and then add the mixture dropwise to the mixed solution obtained in S2, and maintain the pH at 4-6 in a N2 environment React for 12-24h; the volume of mixed ethanol and water is 50-70ml.

S4: Dialyze the solution obtained in S3 in acidified deionized water containing NaCl for 4-7 days to inhibit the oxidation of the catechol group; then freeze and dry to obtain gallic acid-modified chitosan;

S5: Dissolve a certain amount of hyaluronic acid in deionized water, stir evenly, then add a certain amount of sodium periodate and react under light-proof conditions for 3-5 hours; the specific process is to dissolve 1g of hyaluronic acid ( HA) was dissolved in 120 mL of deionized water, stir evenly and then add 1 g of sodium periodate (NaIO4) to it, and react for 3-5 hours under dark conditions;

S6: Add ethylene glycol to the solution reacted in S5 to terminate the reaction, and continue stirring for 2-4 hours; after halving, dialyze the resulting solution in deionized water for 4 days, and finally freeze and dry to obtain aldehyde. Hyaluronic acid; the volume of ethylene glycol to terminate the reaction is between 3-5ml;

S7: 100ug hUCMSCs-Exo is added to 4% HA-ALD, and mixed evenly by ultrasonic; then, the above solution is shaken and mixed with 3wt% CS-GA solution at a volume ratio of 1:1 to 1:2; after mixing evenly, the product can be obtained Injection of Exo@CsGA-HA hydrogel.

Example 2

In this example, first, CS-GA was synthesized by the EDC/NHS method. Under the activation of EDC/NHS, the carboxyl group in gallic acid and the amino group in chitosan react to form an amide bond. Next, aldehyde-modified hyaluronic acid (HA-ALD) was synthesized by using sodium periodate to oxidize the hydroxyl groups on the hyaluronic acid chain. 100ug hUCMSCs-Exo was added to 4% HA-ALD, and mixed with ultrasonic ; Then, the above solution was mixed with 3wt% CS-GA solution at a volume ratio of 1:1 to 1:2 to obtain Exo@CsGA-HA hydrogel. As shown in Figure 2, the ECGH hydrogel showed characteristic absorption bands measured by FTIR, indicating that gallic acid was successfully conjugated to the chitosan backbone, and the gallic acid modification solved the problem of poor water solubility of chitosan. In addition, due to the polyphenol groups on gallic acid, the modified chitosan endows the hydrogel dressing with excellent hemostatic, tissue adhesion, antibacterial and antioxidant properties.

Example 3

In this embodiment, the application of Exo@CsGA-HA hydrogel is provided. Stem cell-derived exosomes are loaded into the hydrogel to prepare a multifunctional hydrogel dressing that can sustainably release exosomes. The multifunctional hydrogel dressing is attached to the surface of the skin wound for 2-3 days, and then replaced with a new hydrogel loaded with exosomes derived from stem cells. Repeat three times as a course of treatment. After two courses of treatment, the patient's wound skin has been significantly improved. At the same time, it will not affect the patient and is highly comfortable. To a certain extent, it provides a new treatment approach for patients with deep wounds.

The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementations described.

Claims (3)

1. A novel hydrogel, characterized in that it includes: a first component and a second component; the first component includes gallic acid-modified chitosan or its derivatives; the second component The components include aldehyde hyaluronic acid or its derivatives; the first component and the second component are chemically dynamically cross-linked, and the reaction cross-linking ratio is between 1:1 and 1:2. 2. The preparation method of a new type of hydrogel as claimed in claim 1, characterized in that it includes the following steps: S1: Use 4-8M HCl to adjust the pH of chitosan to 4-6 and then dissolve it in deionized water to form a 1.5wt% chitosan solution; S2: Heat the chitosan solution obtained in S1 to 50-70°C in a water bath, and use _N2 to deoxidize for 10 minutes, then add gallic acid to the chitosan solution for reaction; S3: Dissolve EDC and NHS in a mixture of ethanol and water in a ratio of 1:1 to 1:2, and then add the mixture dropwise to the mixed solution obtained in S2, and keep the pH at 4-6 in a N2 environment Reaction 12-24h; S4: Dialyze the solution obtained in S3 in acidified deionized water containing NaCl for 4-7 days to inhibit the oxidation of the catechol group; then freeze and dry to obtain gallic acid-modified chitosan CS-GA; S5: Dissolve a certain amount of hyaluronic acid in deionized water, stir evenly, add a certain amount of sodium periodate and react for 3-5 hours under dark conditions; S6: Add ethylene glycol to the solution reacted in S5 to terminate the reaction, and continue stirring for 2-4 hours; after halving, dialyze the resulting solution in deionized water for 4 days, and finally freeze and dry to obtain aldehyde. Hyaluronic acid HA-ALD; S7: Add a certain amount of hUCMSCs-Exo to 4% HA-ALD, and mix evenly with ultrasonic; then, shake and mix the above solution with 3wt% CS-GA solution at a volume ratio of 1:1 to 1:2. ; After mixing evenly, an injectable Exo@CsGA-HA hydrogel is obtained. 3. Application of the preparation method of a new hydrogel as claimed in claim 2 in tissue engineering, wound repair, skin tissue regeneration, and membrane auxiliary materials.