CN110812253A - Hyaluronic acid gel for water light injection and use method thereof - Google Patents

Abstract

The invention discloses a hyaluronic acid gel for water light injection, wherein the hyaluronic acid gel is disulfide-bond cross-linked hyaluronic acid, and the content of hyaluronic acid in the gel is not more than 10 mg/mL. The cross-linked hyaluronic acid gel has unique advantages when being used for hydro-optic injection, is easy to inject through a micro needle head of a hydro-optic needle, can realize good uniform distribution on a subcutaneous superficial layer, and does not generate a bulge phenomenon; meanwhile, the skin moisturizing cream has a moisturizing effect for a longer time than that of uncrosslinked hyaluronic acid, and can effectively improve skin quality.

Description

A kind of hyaluronic acid gel for water light injection and using method thereof

technical field

The invention relates to the field of biomedicine, in particular to a hyaluronic acid gel for hydrophoto injection, and a method for using the hyaluronic acid gel for hydrophoto injection.

Background technique

In recent years, the medical beauty industry at home and abroad has developed rapidly, and various emerging beauty technologies have been developed. Shuiguang injection is one of the most widely carried out medical beauty projects at home and abroad. It can effectively solve the problem that skin care products used on the body surface are not easily absorbed through the epidermal barrier, and can quickly and effectively replenish the skin. Therefore, it can effectively improve skin quality and delay senescence. Water light injection originated from the mesotherapy (Mesotherapy) proposed by French doctor Michal Pistor in 1952. The idea is to inject tiny amounts of therapeutic substances in the local superficial area; after decades of hard work, the current water light acupuncture technology was developed. Water light injection uses negative pressure technology to accurately pierce several extremely thin needles into the subcutaneous place about 1-2 mm, and directly transport repair substances into the epidermis and the dermis or the dermis through the epidermis layer, which solves the problem of active ingredients in skin care products. The problem of inability to effectively penetrate the epidermal barrier.

Hyaluronic acid, also known as hyaluronic acid, is an inherent acidic mucopolysaccharide in the human body and is widely used in various skin care products. The moisture level of the skin is closely related to the content and molecular weight of hyaluronic acid, and high molecular weight hyaluronic acid has stronger water retention properties. With the increase of age and the destruction of daily active oxygen free radicals, the endogenous hyaluronic acid in the skin is continuously degraded and lost, and the water retention function is gradually weakened, which leads to various skin aging symptoms, such as dryness, roughness, dullness , laxity, wrinkles, etc. (Stern et al, Clinics in Dermatology 2008, 26: 106-122; Papakonstantinou et al, Dermatoendocrinol 2012, 4: 253-258).

Supplementing exogenous hyaluronic acid is an important measure to improve skin texture, delay aging symptoms and restore youthfulness. However, due to the existence of the epidermal barrier, the hyaluronic acid applied on the skin surface is difficult to be effectively absorbed, especially the high molecular weight hyaluronic acid with super moisturizing ability. The water-light injection of hyaluronic acid can directly penetrate the epidermal barrier, and can immediately replenish hyaluronic acid in the superficial layer of the skin to achieve the effect of quick hydration and moisturization and achieve the ultimate goal of improving skin quality. At present, water-light injection mainly supplements exogenous hyaluronic acid by superficial injection, and also contains other repairing nutrients appropriately. CN106074213A discloses a hyaluronic acid gel for water-light injection, the composition of which includes 10-30 parts of sodium hyaluronate, 0.5-3 parts of glycerin, 0.5-1.5 parts of mannitol, 1-9 parts of pH regulator and 25-45 parts of isotonicity regulator. CN 105233270A discloses a pharmaceutical composition for water and light therapy and its application. The composition comprises: 0.01-0.5wt% of high molecular weight sodium hyaluronate, 0.01-0.3wt% of medium molecular weight sodium hyaluronate, 0.01-1wt% % low molecular weight sodium hyaluronate, 0.01-1wt% sodium oligomeric hyaluronate, 0.01-5wt% collagen, 0.05-1.8wt% adjuvant, recombinant human epidermal growth factor, the balance is water, reconstituted The concentration of human epidermal growth factor is 0.5~10μg/ml; the molecular weight of high molecular weight sodium hyaluronate is 1.3~2 million daltons, the molecular weight of medium molecular weight sodium hyaluronate is 50~1 million daltons, and the low molecular weight transparent The molecular weight of sodium humate is 50,000-300,000 daltons, and the molecular weight of oligomeric sodium hyaluronate is 3,000-8,000 daltons.

However, under the action of hyaluronidase in the body, hyaluronic acid is rapidly degraded into small molecular fragments, which enter the body fluid circulation and are absorbed and metabolized, losing the function of local moisturizing and moisturizing in the skin; in the skin, the half-life of hyaluronic acid is less than 1 days (Laurent et al., Exp Physiol 1991, 76:695-703). Therefore, although water-light injection can quickly replenish hyaluronic acid locally, it can only replenish moisture in a short period of time, and it is difficult to achieve longer-term effects such as improving skin quality, delaying aging and restoring youthfulness. For example, the research results of Amin et al. (Dermatol Surg 2006, 32: 1467-1472) and El-Domyati et al. (International Journal of Dermatology 2012, 51: 913-919) indicated that the efficacy of hyaluronic acid hydrophoto injection needs to be further improved.

等)在皮下的降解吸收时间可长达6个月以上，被广泛用于皱纹注射填充。然而，当前交联透明质酸凝胶产品的含量很高(通常不小于20mg/mL)(Edsman等，Dermatol Surg 2012,38:1170-1179)，亦即含水量通常不大于98％(交联透明质酸自身重量约49倍的含水量)，补水保湿性能较差；并且，该等交联透明质酸凝胶产品还具有较大的凝胶强度，需粉碎为颗粒状后才能使用，且推挤力较大，很难通过水光针极细针头进行浅表层注射；此外，该等交联透明质酸凝胶产品的流动性差，无法在水光注射的浅表层均匀分布，且容易形成鼓包且在短期内无法降解消失。因此，当前交联透明质酸凝胶产品用于水光注射用途存在诸多局限性。Cross-linking modification can delay the degradation and absorption of hyaluronic acid in the body, such as 1,4-butanediol diglycidyl ether (BDDE) cross-linked hyaluronic acid gel (

etc.) The degradation and absorption time under the skin can be as long as more than 6 months, and it is widely used for wrinkle injection filling. However, current cross-linked hyaluronic acid gel products have a high content (usually not less than 20 mg/mL) (Edsman et al., Dermatol Surg 2012, 38: 1170-1179), i.e. the water content is usually not more than 98% (cross-linked The water content of hyaluronic acid is about 49 times of its own weight), and the moisturizing and moisturizing performance is poor; and, these cross-linked hyaluronic acid gel products also have relatively large gel strength, and can only be used after being pulverized into granules, and The pushing force is large, and it is difficult to perform superficial injection through the ultra-fine needle of the water light needle; in addition, these cross-linked hyaluronic acid gel products have poor fluidity and cannot be evenly distributed in the superficial layer of water light injection, and are easy to form It is bulging and cannot be degraded and disappeared in a short time. Therefore, the current cross-linked hyaluronic acid gel products have many limitations in the application of water-light injection.

SUMMARY OF THE INVENTION

In order to solve the problem of short duration of moisturizing and moisturizing effect due to degradation and absorption of hyaluronic acid by water-light injection in the prior art, and also to solve the problem that the cross-linked hyaluronic acid gel in the prior art has a long degradation and absorption time but is not suitable for In view of the problem of hydrophoto injection, the present application provides a disulfide cross-linked hyaluronic acid gel for hydrophoto injection, which has longer degradation and absorption time and longer maintenance of moisturizing and moisturizing than existing hyaluronic acid. Time, low impurity toxicity, suitable for water light injection, and will not produce the bulging phenomenon that current cross-linked hyaluronic acid gel products are prone to occur, so the skin texture can be more effectively improved through water light injection.

The present invention is achieved through the following technical solutions:

A hyaluronic acid gel for hydrophoto injection, wherein the hyaluronic acid is a disulfide bond cross-linked hyaluronic acid, and the content of the hyaluronic acid in the hyaluronic acid is not more than 10 mg/mL.

In the present invention, the content of the disulfide-linked hyaluronic acid is expressed as the weight (mg/mL) of the cross-linked hyaluronic acid contained in the unit volume of the disulfide-linked hyaluronic acid gel. The content of the cross-linked hyaluronic acid for hydrophoto injection according to the present invention is preferably between 4 and 8 mg/mL, particularly preferably between 5.5 and 7 mg/mL.

Compared with the content of the current cross-linked hyaluronic acid gel products (usually not less than 20 mg/mL), the content of the disulfide-bonded cross-linked hyaluronic acid gel for hydrophoto injection according to the present invention is low, only the current less than 50% of the cross-linked hyaluronic acid gel product; therefore, the disulfide cross-linked hyaluronic acid gel for hydrophoto injection of the present invention has lower strength, better fluidity, and is easy to pass through water The ultra-fine needle of the light needle is used for injection and uniform distribution in the superficial layer of the skin. In addition, the water content of the disulfide cross-linked hyaluronic acid gel for hydrophoto injection according to the present invention is not less than 99% (99 times and above the weight of the disulfide cross-linked hyaluronic acid), and can further It absorbs water and retains water to about 1000 times its own weight of disulfide cross-linked hyaluronic acid, so it has a water-retention capacity similar to that of non-cross-linked hyaluronic acid.

In the present invention, the method similar to that disclosed in the prior art patent document CN 101721349A of the applicant of the present invention can be used to prepare the disulfide-crosslinked hyaluronic acid gel for hydrophoto injection according to the present invention. The preparation method realizes cross-linking of disulfide bonds through the oxidation of the hyaluronic acid thiolated derivative aqueous solution under the action of oxygen (oxygen in the air and/or dissolved oxygen in the aqueous solution), and has the advantages of not needing to add a cross-linking agent, and the by-product is: The advantages of water, simple production process and no impurities, etc., avoid the potential toxic and side effects caused by the complex process of the current cross-linked hyaluronic acid gel products and the residual cross-linking agent.

As known to those skilled in the art, in the current preparation process of cross-linked hyaluronic acid gel products, immersion dialysis is routinely used for purification, that is, the gel after the cross-linking reaction is soaked in a large amount of water or buffer. In the salt solution, the residual cross-linking agent and other impurities in the cross-linked gel are removed by dialysis; this purification process requires the cross-linked gel to have high strength, so the current cross-linked hyaluronic acid gel products have high strength. , not suitable for water injection. On the contrary, in the present invention, the above-mentioned preparation method of the disulfide cross-linked hyaluronic acid gel for hydrophoto injection does not require a purification process, and is especially suitable for preparing cross-linked products with low strength and certain fluidity. Linked gel, suitable for water and light injection.

In the present invention, the disulfide bond cross-linked hyaluronic acid gel for water-light injection described in the present invention can be prepared by using the hyaluronic acid thiolated derivatives disclosed in the applicant's prior art patent document CN 102399295A glue. These hyaluronic acid thiolated derivatives better maintain the original structure, physiological function and biocompatibility of hyaluronic acid, and can achieve effective disulfide bond cross-linking and delay metabolism and absorption in the body. Combined hyaluronic acid for longer hydration and moisturizing maintenance time.

The hyaluronic acid of the present invention can be in the form of its salts (such as sodium salt, potassium salt, zinc salt, calcium salt, etc.) and/or the form of its derivatives (such as carboxymethylated hyaluronic acid, acetylated hyaluronic acid, etc.) acid, etc.).

In the present invention, the hyaluronic acid thiolated derivatives refer to hyaluronic acid derivatives containing thiol groups, which can be prepared by thiol modification of hyaluronic acid, including various hyaluronic acid derivatives further modified by thiol groups thiolated derivatives prepared by chemical modification. The side chain carboxyl groups, side chain hydroxyl groups, and reducing end groups of hyaluronic acid or its salts or derivatives are usually active functional groups that can be modified by thiolation. The preparation methods of hyaluronic acid thiolated derivatives can all be used to prepare the hyaluronic acid thiolated derivatives of the present invention.

In the present invention, hyaluronic acid thiolated derivatives with various sulfhydryl contents can be used to prepare the disulfide bridge-crosslinked hyaluronic acid gel for hydrophoto injection according to the present invention. The sulfhydryl content is expressed as the number of micromoles (μmol/g) of the sulfhydryl groups contained in each gram of hyaluronic acid thiolated derivatives. between g.

Another object of the present invention is to provide a method for using the disulfide bridge-crosslinked hyaluronic acid gel for hydrophoto injection.

(德玛莎)等水光注射仪通过五针或九针等极细负压针头进行水光注射。然而，当本发明所述的用于水光注射的二硫键交联透明质酸凝胶的含量较高时(如4～10mg/mL时)，直接进行水光注射的推挤力较大，此时可在水光注射前适当稀释至较低含量(通常小于4mg/mL时)，即可顺利进行水光注射。稀释过程可在两通或三通接头连接的注射器中进行，其中一支注射器装有本发明所述的用于水光注射的二硫键交联透明质酸凝胶，另一只注射器装有生理盐水、与体液等渗的缓冲液或营养活性物质溶液(如含有生长因子、氨基酸、维生素等的溶液)，两支注射器往复推挤即可实现物理稀释混合。当前水光注射除了补充透明质酸外，通常也希望同时适当补充其它修复营养物质；该需求可方便通过上述物理混合过程实现，以实现协同的水光注射补水保湿等效果。When the content of the disulfide cross-linked hyaluronic acid gel for hydro-optical injection of the present invention is relatively low (usually less than 4 mg/mL), the hydro-optical injection method well known to those skilled in the art can be directly used. Hydrolight injections such as Derma

(DeMarsha) and other water-light injection devices perform water-light injection through ultra-fine negative pressure needles such as five needles or nine needles. However, when the content of the disulfide cross-linked hyaluronic acid gel for hydrophoto injection according to the present invention is relatively high (for example, 4-10 mg/mL), the pushing force of direct hydrophoto injection is relatively large. , at this time, it can be properly diluted to a lower content (usually less than 4 mg/mL) before the water-light injection, and the water-light injection can be carried out smoothly. The dilution process can be carried out in syringes connected with two-way or three-way joints, one of the syringes is filled with the disulfide cross-linked hyaluronic acid gel for water-light injection according to the present invention, and the other syringe is filled with Physiological dilution and mixing of physiological saline, buffer solution isotonic with body fluids or nutritionally active substance solutions (such as solutions containing growth factors, amino acids, vitamins, etc.) can be achieved by pushing back and forth between two syringes. In addition to supplementing hyaluronic acid, the current water and light injection usually hopes to properly supplement other repair nutrients at the same time; this requirement can be easily achieved through the above physical mixing process, so as to achieve synergistic water and light injection for moisturizing and other effects.

The beneficial effects of the present invention are:

The disulfide bond cross-linked hyaluronic acid gel for hydrophoto injection of the present invention overcomes the shortcomings of the current cross-linked hyaluronic acid gel products for hydrophoto injection, and has lower content and better Liquidity, easy to inject through the ultra-fine needle of the water light needle, can achieve good and uniform distribution in the subcutaneous superficial layer, without bulging phenomenon; at the same time, it has a longer hydrating and moisturizing effect than uncross-linked hyaluronic acid, which can effectively Improve skin texture.

The disulfide cross-linked hyaluronic acid gel for water-light injection according to the present invention can be conveniently prepared by the thiolated hyaluronic acid derivative, and has the advantages of no need to add a cross-linking agent, simple preparation process, no impurities, etc. There are many advantages, which can avoid the complicated process of the current cross-linked hyaluronic acid gel products and the toxic and side effects caused by the residual cross-linking agent.

In addition, the disulfide cross-linked hyaluronic acid gel for water-light injection of the present invention can also be conveniently physically mixed with other nutritionally active substances before use, so as to achieve the synergistic effect of water-light treatment.

Description of drawings

Figure 1. The effect of disulfide cross-linked sodium hyaluronate gel on skin water content after hydrophoto injection

Figure 2. Effects of disulfide cross-linked sodium hyaluronate gel on skin elasticity after hydrophoto injection.

Figure 3. Effect of disulfide cross-linked sodium hyaluronate gel on skin wrinkle depth after hydrophoto injection.

Detailed ways

The embodiments of the present invention will be described in detail below with reference to the examples, but those skilled in the art will understand that the following examples are only used to illustrate the present invention, and should not be regarded as limiting the scope of the present invention.

Example 1: Preparation of disulfide cross-linked hyaluronic acid gel

Hyaluronic acid thiolated derivatives were prepared from sodium hyaluronate with a molecular weight of 180KDa by the method reported by Shu et al. (Shu et al., Biomacromolecules 2002, 3:1304-1311), and the thiol content was 24 μmol/g and 38 μmol, respectively. /g and 57 μmol/g.

Dissolving the above-mentioned hyaluronic acid thiolated derivative to obtain 10ml aqueous solution, the contents are respectively 3, 4, 5.5, 6.5, 7, 8 and 10mg/mL; adjust the pH value of the solution to 7.4, transfer into 25ml sterile glass after sterilization filtration Container; airtight and stored at room temperature for 4 weeks, the solution loses fluidity and forms a disulfide cross-linked hydrogel.

Example 2: Evaluation of Injectable Properties of Disulfide Cross-Linked Hyaluronic Acid Gels

(德玛莎)2代水光注射仪，测试实施例1所制备凝胶的通过常规水光注射针头(九针)的可注射性，试验结果如下：Adopt Derma

(DeMarsha) 2nd generation water-light injection instrument, test the injectability of the gel prepared in Example 1 through conventional water-light injection needles (nine needles), and the test results are as follows:

When the content of cross-linked hyaluronic acid is 3mg/mL and 4mg/mL, it usually has good injectability; while the content is ≥ 5.5mg/mL, it is difficult to inject through the water-light injector.

Example 3: Evaluation of injectable properties of disulfide-crosslinked hyaluronic acid gels after dilution

The gel prepared in Example 1 (the content of cross-linked hyaluronic acid was: 5.5 mg/mL, 6.5 mg/mL, 7 mg/mL, 8 mg/mL and 10 mg/mL; the thiol content of the thiolated derivative was 38 μmol /g) Physically mixed and diluted with normal saline at volume ratios of 1:1, 1:1.5 and 1:2. The dilution process was carried out in syringes connected with two-way joints, one of the syringes was filled with the gel prepared in Example 1 (1mL), and the other was filled with an appropriate volume of physiological saline (1mL, 1.5mL, 3mL), Push back and forth 60 to 80 times for physical dilution and mixing.

(德玛莎)2代水光注射仪，测试稀释后凝胶通过常规水光注射针头(九针)的可注射性，试验结果如下：Adopt Derma

(DeMartha) 2nd generation hydro-optical injection instrument to test the injectability of the diluted gel through conventional hydro-optical injection needles (nine needles). The test results are as follows:

等)的强度大且粒径较大，在同等条件下即使按照更高倍数的体积比进行稀释，仍极易堵塞注射针头。When diluted to a content of ≤4mg/mL, injection through a water-light injector can be achieved; the lower the content after dilution, the better the injectability. While current cross-linked hyaluronic acid gel products (

etc.) have high strength and large particle size, under the same conditions, even if it is diluted with a higher volume ratio, it is still very easy to block the injection needle.

Example 4: Evaluation of water absorption and water retention performance of disulfide cross-linked hyaluronic acid gel

Using the same dilution process as Example 3, the gel prepared in Example 1 and the physiological saline were physically mixed and diluted according to the volume ratio of 1:2, and then placed in a glass bottle, and allowed to stand at room temperature for 1 hour. The delamination phenomenon between the water phase and the gel phase shows that the gel has good water absorption and water retention properties (up to about 1000 times the weight of the cross-linked hyaluronic acid).

Example 5: Evaluation of injectable properties of disulfide cross-linked hyaluronic acid gel after dilution

(德玛莎)2代水光注射仪，测试各稀释后凝胶通过常规水光注射针头(九针)的可注射性；试验结果表明各稀释后凝胶均具有良好的可注射性能。Using the same mixing and dilution process as in Example 3, the gel prepared in Example 1 (with a content of 6.5 mg/mL; the content of sulfhydryl groups of the thiolated derivative was 57 μmol/g) was mixed with five aqueous solutions (with a content of 0.5 mg/ mL of vitamin C, vitamin B2, arginine, lysine and glutamine) were physically mixed and diluted in a volume ratio of 1:1 and 1:2. Adopt Derma

(DeMarsha) 2nd generation hydro-optical injection instrument to test the injectability of the diluted gels through conventional hydro-optical injection needles (nine needles); the test results show that the diluted gels have good injectability.

Example 6: Preparation of Disulfide Cross-Linked Hyaluronic Acid Gel

Hyaluronic acid thiolated derivatives were prepared from sodium hyaluronate with molecular weights of 300KDa and 1,500KDa by the method reported by Shu et al. (Shu et al., Biomacromolecules 2002, 3:1304-1311), and their thiol content was 33 μmol/ g and 40 μmol/g.

Dissolving the above-mentioned hyaluronic acid thiolated derivative to obtain 10ml aqueous solution, the contents are respectively 3, 4, 5.5, 6.5, 7, 8 and 10mg/mL; adjust the pH value of the solution to 7.4, transfer into 25ml sterile glass after sterilization filtration bottle; kept at room temperature for 4 weeks, the solution lost its fluidity and formed a disulfide cross-linked hydrogel.

Example 7: Injectable properties of disulfide-crosslinked hyaluronic acid gels

(德玛莎)2代水光注射仪，测试实施例6所制备凝胶的通过常规水光注射针头(九针)的可注射性。本实施例的试验结果表明：当含量为3mg/mL和4mg/mL时，通常具有较好的可注射性；而浓度≥5.5mg/mL，则很难通过水光注射仪进行注射。Adopt Derma

(DeMarsha) 2nd generation hydro-optical injection instrument to test the injectability of the gel prepared in Example 6 through conventional hydro-optical injection needles (nine needles). The test results of this example show that: when the content is 3mg/mL and 4mg/mL, it usually has good injectability; while the concentration is ≥ 5.5mg/mL, it is difficult to inject through a water-light injector.

Example 8: Evaluation of injectable properties of disulfide-crosslinked hyaluronic acid gels after dilution

The gel prepared in Example 6 (contents were: 5.5mg/mL, 6.5mg/mL, 7mg/mL, 8mg/mL and 10mg/mL) and normal saline were 1:1, 1:1.5 and 1 by volume :2 for physical mixing and dilution. The dilution procedure was the same as in Example 3.

Adopt Derma (DeMarsha) 2nd generation hydro-optical injection instrument to test the injectability of the diluted gel through conventional hydro-optical injection needles (nine needles). The test results of this example show that when diluted to a content of ≤4 mg/mL, it has good injectability.

Example 9: Evaluation of water-light injection effect of disulfide cross-linked hyaluronic acid gel

2代水光注射仪，常规九针水光注射针头)。Eight healthy volunteers (4 in the experimental group and 4 in the control group) were selected for facial water-light injection (Derma

2nd generation water-light injection instrument, conventional nine-needle water-light injection needle).

The samples used in the test group were: 2 mL of the gel prepared in Example 1 (the content of cross-linked hyaluronic acid was 6.5 mg/mL; the content of sulfhydryl groups of thiolated derivatives was 38 μmol/g), which was mixed and diluted with 3 mL of normal saline before use. The mixing and dilution process was the same as in Example 3; the total sample volume was 5 mL, and the final content of cross-linked sodium hyaluronate was 2.6 mg/mL. The samples used in the control group were the same volume and the same concentration of non-crosslinked sodium hyaluronate aqueous solution (molecular weight 1.5MDa).

At different time points after facial water light injection, the skin moisture content test and the improvement test of wrinkles and skin elasticity were carried out on the same site respectively.

The relative increase (%) of skin moisture before and after injection was tested with a skin moisture meter, the relative increase in skin elasticity (%) before and after injection was tested with a skin elasticity tester, and the relative decrease in average depth of wrinkles before and after injection was tested with a fast three-dimensional imaging system Evaluation.

The test results of this embodiment are shown in Figures 1-3. Compared with the non-cross-linked hyaluronic acid control group, the disulfide cross-linked hyaluronic acid gel has a better water-light treatment effect, and the maintenance time is longer; at the same time, no bulging phenomenon was found in all test subjects in the treatment group, indicating that the two The sulfur-crosslinked hyaluronic acid gel has good fluidity and can be uniformly distributed in the superficial layer of water-light injection.

The above-mentioned embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited by the examples, and any other changes, modifications, combinations, substitutions, and simplifications made without departing from the spirit and principle of the present invention All should be equivalent alternatives, and all are included within the protection scope of the present invention.

Claims (10)

1. A hyaluronic acid gel for use in water light injection, characterized in that the hyaluronic acid is disulfide-bond-crosslinked hyaluronic acid, and wherein the content of disulfide-bond-crosslinked hyaluronic acid is not more than 10 mg/mL.

2. The hyaluronic acid gel for water light injection according to claim 1, wherein the content of the disulfide-bond cross-linked hyaluronic acid is between 4 and 8 mg/mL.

3. The hyaluronic acid gel for water light injection according to claim 2, wherein the content of the disulfide-bond cross-linked hyaluronic acid is between 5.5 and 7 mg/mL.

4. The hyaluronic acid gel for water light injection according to claim 1, wherein the crosslinked hyaluronic acid gel for water light injection is prepared by thiolating derivatives of hyaluronic acid.

5. The hyaluronic acid gel for water light injection according to claim 4, wherein the thiol content of the thiol-modified derivative of hyaluronic acid is between 10 and 50 μmol/g.

6. The hyaluronic acid gel for water light injection according to claim 5, wherein the thiol content of the thiol-modified derivative of hyaluronic acid is between 20 and 40 μmol/g.

7. The method for using the hyaluronic acid gel for water light injection according to any of claims 1-6, wherein the disulfide-bond crosslinked hyaluronic acid gel is diluted with a diluent by physical mixing until the content of the disulfide-bond crosslinked hyaluronic acid is not more than 4mg/mL before use.

8. The method for using the hyaluronic acid gel for water light injection according to claim 7, wherein the diluent is physiological saline or a buffered saline solution isotonic with body fluid.

9. The method of using the hyaluronic acid gel for water light injection according to claim 7, wherein the diluent contains a nutritional active substance.

10. The method for using the hyaluronic acid gel for water light injection according to claim 9, wherein the nutraceutically active substance is an amino acid, a vitamin or a growth factor.

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