CN117800299A - Calcium silicate-calcium phosphate crystalline phase composite material and application thereof - Google Patents

Abstract

The invention discloses a calcium silicate-calcium phosphate crystalline phase composite material and application thereof, wherein the calcium silicate-calcium phosphate crystalline phase composite material is prepared by a preparation method A or a preparation method B; wherein, the preparation method A comprises the following steps: obtaining a mixed system containing tetraethyl silicate, ethanol and water, regulating the pH value of the mixed system to 1-2 by using acid, and then adding calcium salt to obtain a first component; obtaining a mixed system containing phosphate, calcium salt and water to obtain a second component; and uniformly mixing the first component and the second component, stirring at 50-80 ℃, drying at 110-130 ℃ for 11-13h, sintering, cooling, mixing with ethanol, grinding, and sieving to obtain the calcium silicate-calcium phosphate crystalline phase composite material. The calcium silicate-calcium phosphate crystalline phase composite material is a milder active composition and can be applied to the fields of oral cavity, cosmetics and skin mucosa repair.

Description

Calcium silicate-calcium phosphate crystal phase composite materials and their applications

Technical field

The invention belongs to the technical field of composite materials, and specifically relates to a calcium silicate-calcium phosphate crystal phase composite material and its application.

Background technique

Calcium silicate inorganic active materials were first used as the main component in new dental restorations in the 1990s, demonstrating their good antibacterial properties and biocompatibility. Subsequently, a large number of studies have proven that calcium silicate inorganic active materials have good biological activity and can induce the formation of hydroxyapatite (HA). Numerous research results have shown that calcium silicate inorganic active materials can block dentinal tubules through a self-curing process and induce dentin remineralization under physiological conditions. They have great potential to be used to effectively treat dentin hypersensitivity in the future. It can effectively avoid thermal damage to surrounding tissues; it has good mechanical strength and can meet the supporting properties required by bone repair materials; it has good biocompatibility and osteogenesis and can be used as an injectable self-curing bone repair material. Bone repair surgery in dentistry and orthopedics. In addition, the hydration process of calcium silicate inorganic active materials can release a large amount of Ca(OH) ₂ , and its strong alkalinity can exert antibacterial and anti-inflammatory effects. In the prior art, toothpastes that add calcium silicate inorganic active materials (bioactive glass) as effective active ingredients have appeared. Oral clinical studies have found that such active ingredients can react with water and saliva in the mouth during use. Rapid and sustained reaction, releasing calcium and silicate ions, keeping the oral pH slightly alkaline, inhibiting bacterial growth, improving the oral environment, preventing bacteria from continuing to produce acid on the enamel surface and damaging the enamel; at the same time, the filling is damaged Tooth enamel is fused and regenerated to achieve repair purposes.

However, further in vivo and in vitro studies revealed that the sustained high alkaline environment of calcium silicate inorganic active materials also has certain negative effects on tissue repair. For example, in oral repair, its irritation to tissues can cause discomfort and allergic reactions in patients, which greatly affects the progress and effect of tissue repair. These negative effects greatly limit the clinical application of calcium silicate materials. Its essence lies in the fact that the molecular structure of calcium silicate materials is easily hydrolyzed.

Therefore, in view of the above technical problems, it is necessary to provide a new material to solve the above problems.

The information disclosed in this Background section is merely intended to enhance an understanding of the general background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art that is already known to a person of ordinary skill in the art.

Summary of the invention

The purpose of the present invention is to provide a calcium silicate-calcium phosphate crystal phase composite material, which is a milder active composition and can be used in the field of oral cavity, cosmetics and skin and mucous membrane repair.

In order to achieve the above object, a technical solution provided by a specific embodiment of the present invention is as follows: a calcium silicate-calcium phosphate crystal phase composite material, prepared by preparation method A or preparation method B;

The preparation method A includes the following steps:

A1. Obtain a mixed system containing tetraethyl silicate, ethanol and water, adjust the pH value of the mixed system to 1-2 with acid, and then add calcium salt to obtain the first component;

A2. Obtain a mixed system containing phosphate, calcium salt and water to obtain the second component;

A3. Mix the first component and the second component evenly, stir at 50-80°C, dry at 110-130°C for 11-13 hours, sinter, mix with ethanol after cooling, grind and pass Sieve to obtain the calcium silicate-calcium phosphate crystal phase composite material;

The preparation method B includes the following steps:

B1. Obtain a mixed system containing phosphate, tetraethyl silicate, ethanol, calcium salt and water, adjust the pH value of the mixed system to 1-2 with acid, stir, and dry at 110-130°C for 36 -48h;

B2. The dried product is sintered, cooled, mixed with ethanol, ground and sieved to obtain the calcium silicate-calcium phosphate crystal phase composite material.

In one or more embodiments of the present invention, the phosphate is at least one of ammonium hydrogen phosphate, sodium hydrogen phosphate and potassium dihydrogen phosphate; and/or,

The calcium salt includes at least one of water-soluble calcium oxalate, calcium nitrate, calcium citrate, calcium gluconate, calcium hypochlorite, and calcium acetate; and/or,

In step A1 and/or step B1, the acid used to adjust the pH value of the mixed system is any one of nitric acid, hydrochloric acid and acetic acid.

In one or more embodiments of the present invention, the sintering step in the preparation method A and/or the preparation method B specifically includes:

The dried product is heated to 1200-1400°C at a heating rate of 5-10°C/min and kept at this temperature for 3-6 hours.

In one or more embodiments of the present invention, in step A1 of the preparation method A, the step of obtaining a mixed system containing tetraethyl silicate, ethanol and water includes:

Tetraethyl silicate and ethanol are mixed uniformly in a molar ratio of (0.1-0.4):1, and water is added.

In one or more embodiments of the present invention, in step A1 of the preparation method A, the molar ratio of calcium salt to tetraethyl silicate is (0.5-1):1.

In one or more embodiments of the present invention, in step A2 of the preparation method A, the step of obtaining a mixed system containing phosphate, calcium salt and water includes:

Mix the phosphate and calcium salt evenly at a molar ratio of 1: (1-1.5) and dissolve them in water.

In one or more embodiments of the present invention, in the preparation method A, the molar ratio of tetraethyl silicate in the first component to the phosphate in the second component is (0.5- 2):1.

In one or more embodiments of the present invention, in the preparation method B,

The molar ratio of the phosphate to tetraethyl silicate is (0.5-2):1;

The molar ratio of tetraethyl silicate to ethanol is (0.1-0.4): 1

The molar ratio of the phosphate to the calcium salt is 1:(1-1.5).

In one or more embodiments of the present invention, the stirring step in step B1 of the preparation method B is specifically:

When the calcium salt is a weak electrolyte, the mixed system after adjusting the pH value is magnetically stirred for 50-70 minutes at room temperature to form a white slurry; or,

When calcium salt is a strong electrolyte, the mixed system with adjusted pH value is magnetically stirred in a constant temperature water bath at 50-80°C for 50-70 minutes to form a sol state, and then aged at 50-80°C for 12-36 hours to form a wet gel. .

A specific embodiment of the present invention also provides an application of the above-mentioned calcium silicate-calcium phosphate crystal phase composite material in the field of oral cavity, cosmetics and skin and mucous membrane repair.

Compared with the prior art, the calcium silicate-calcium phosphate crystal phase composite material of the present invention can be made into a composite phase of silicic acid and phosphate groups through the above-mentioned preparation method A or preparation method B, using strong and weak electrolytes of calcium salts, The silicate-calcium phosphate precursor is slowly formed, and then undergoes sintering treatment to obtain a calcium phosphate/wollastonite material with a composite crystal phase structure, that is, the calcium silicate-calcium phosphate crystal phase composite material of the present invention.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are only These are some embodiments recorded in the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without exerting creative efforts.

FIG1 is a flow chart of a method A for preparing a calcium silicate-calcium phosphate crystalline composite material in one embodiment of the present invention;

Figure 2 is a flow chart of method B for preparing calcium silicate-calcium phosphate crystal phase composite material in one embodiment of the present invention;

FIG3 is an XRD diagram of the calcium silicate-calcium phosphate crystalline composite material in Examples 1-4 of the present invention;

Figure 4 is an FTIR spectrum of the calcium silicate-calcium phosphate crystal phase composite material in Examples 1-4 of the present invention;

FIG5 is a SEM photograph of the calcium silicate-calcium phosphate crystalline composite material in Examples 1-4 of the present invention;

Figure 6 is a particle size distribution diagram of the calcium silicate-calcium phosphate crystal phase composite material in Examples 1-4 of the present invention;

FIG7 is an XRD photograph of the bioglass in Comparative Example 1 of the present invention after being reacted in the SBF solution for different time periods;

FIG8 is a SEM photograph of the bioglass in Comparative Example 1 of the present invention after being reacted in the SBF solution for different time periods;

Figure 9 is an SEM photo of the calcium silicate-calcium phosphate crystal phase composite material after reacting in SBF solution for different times in Examples 1-4 of the present invention;

Figure 10 is an XRD pattern of the calcium silicate-calcium phosphate crystal phase composite material after reacting in SBF solution for different times in Examples 1-4 of the present invention.

Detailed ways

In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described The embodiments are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts should fall within the scope of protection of the present invention.

As shown in FIGS. 1 and 2 , a calcium silicate-calcium phosphate crystalline composite material in one embodiment of the present invention is prepared by preparation method A or preparation method B;

The preparation method A includes the following steps:

A1. Obtain a mixed system containing tetraethyl silicate, ethanol and water, adjust the pH value of the mixed system to 1-2 with acid, and then add calcium salt to obtain the first component.

In step A1, the purpose of adding calcium salt is to form a weakly bound calcium silicate cluster structure.

Specifically, the steps for obtaining a mixed system containing tetraethyl silicate, ethanol and water may be as follows: uniformly mix tetraethyl silicate and ethanol at a molar ratio of (0.1-0.4):1, and add water.

It can be understood that water acts as a solvent, so an appropriate amount of water is sufficient. For example, the volume of water can be equal to the sum of the volumes after mixing tetraethyl silicate and ethanol. Of course, it can also be more or less than the above-mentioned sum of volumes. .

Among them, the molar ratio of calcium salt to tetraethyl silicate is (0.5-1):1.

Among them, the acid used to adjust the pH value of the mixed system is any one of nitric acid, hydrochloric acid and acetic acid. Preferably, nitric acid is used to adjust the pH of the mixed system.

A2. Obtain a mixed system containing phosphate, calcium salt and water to obtain the second component;

Specifically, the step of obtaining a mixed system containing phosphate, calcium salt and water may be: mix the phosphate and calcium salt evenly at a molar ratio of 1: (1-1.5), and dissolve them in water. It can be understood that this molar ratio mainly refers to the molar ratio of phosphorus and calcium in the second component. Water acts as a solvent, so an appropriate amount of water is sufficient. For example, the volume of water in step A2 can be the same as the volume of water in step A1. Of course, it can also be more or less than the volume of water in step A1.

In step A2, the purpose of adding calcium salt is to form a weakly bound calcium phosphate cluster structure.

A3. Mix the first component and the second component evenly, stir at 50-80°C, dry at 110-130°C for 11-13 hours, sinter, mix with ethanol after cooling, grind and pass Sieve to obtain the calcium silicate-calcium phosphate crystal phase composite material.

Specifically, the molar ratio of tetraethyl silicate in the first component to the phosphate in the second component is (0.5-2):1.

Specifically, the sintering step may specifically include: heating the dried product to 1200-1400°C at a heating rate of 5-10°C/min, and then maintaining the temperature for 3-6 hours. Among them, the sintering step can be performed in a Mabo furnace.

Specifically, the cooling process may be: quenching the sintered product in air. Among them, quenching in air can be understood as placing the product at 1200-1400°C directly at room temperature and in the air for cooling, and then cooling it to room temperature. Room temperature can be considered to be about 25°C, for example, room temperature can be understood as 20-30°C.

It can be understood that in preparation method A, the phosphate can be at least one of ammonium hydrogen phosphate, sodium hydrogen phosphate and potassium dihydrogen phosphate; wherein, ammonium hydrogen phosphate can be considered to be ammonium hydrogen phosphate or diammonium hydrogen phosphate, Sodium hydrogen phosphate can be considered as sodium hydrogen phosphate or disodium hydrogen phosphate; calcium salts include at least one of water-soluble calcium oxalate, calcium nitrate, calcium citrate, calcium gluconate, calcium hypochlorite, and calcium acetate.

Among them, the choice of calcium salt is different (that is, whether the calcium salt is a strong electrolyte or a weak electrolyte), which can lead to differences in the tissue structure, biological activity and other properties of the final calcium silicate-calcium phosphate crystal phase composite material.

The preparation method B includes the following steps:

B1. Obtain a mixed system containing phosphate, tetraethyl silicate, ethanol, calcium salt and water, adjust the pH value of the mixed system to 1-2 with acid, stir, and dry at 110-130°C for 36 -48h.

Specifically, the molar ratio of the phosphate to tetraethyl silicate is (0.5-2):1; the molar ratio of the calcium salt to tetraethyl silicate is (0.5-1):1; the phosphoric acid The molar ratio of salt to calcium salt is 1: (1-1.5).

It can be understood that in preparation method B, the phosphate can be at least one of ammonium hydrogen phosphate, sodium hydrogen phosphate and potassium dihydrogen phosphate, wherein the ammonium hydrogen phosphate can be considered to be ammonium hydrogen phosphate or diammonium hydrogen phosphate, Sodium hydrogen phosphate can be considered as sodium hydrogen phosphate or disodium hydrogen phosphate; calcium salts include at least one of water-soluble calcium oxalate, calcium nitrate, calcium citrate, calcium gluconate, calcium hypochlorite, and calcium acetate.

Among them, the acid used to adjust the pH value of the mixed system is any one of nitric acid, hydrochloric acid and acetic acid. Preferably, nitric acid is used to adjust the pH of the mixed system.

Among them, the choice of calcium salt is different (that is, whether the calcium salt is a strong electrolyte or a weak electrolyte), which can lead to differences in the tissue structure, biological activity and other properties of the final calcium silicate-calcium phosphate crystal phase composite material.

specific. The specific mixing steps in step B1 are:

When the calcium salt is a weak electrolyte, stir the pH-adjusted mixed system magnetically at room temperature for 50-70 minutes to form a white slurry.

When calcium salt is a strong electrolyte, the mixed system with adjusted pH value is magnetically stirred in a constant temperature water bath at 50-80°C for 50-70 minutes to form a sol state, and then aged at 50-80°C for 12-36 hours to form a wet gel. .

B2. The dried product is sintered, cooled, mixed with ethanol, ground and sieved to obtain the calcium silicate-calcium phosphate crystal phase composite material.

Specifically, the sintering step may include: heating the dried product to 1200-1400°C at a heating rate of 5-10°C/min n, and then maintaining the temperature for 3-6 hours.

Specifically, the cooling process may be: quenching the sintered product in air. Among them, quenching in air can be understood as placing the product at 1200-1400°C directly at room temperature and in the air for cooling, and then cooling it to room temperature. Room temperature can be considered to be about 25°C, for example, room temperature can be understood as 20-30°C.

It should be noted that the ethanol used in preparation method A or preparation method B can be absolute ethanol; the water can be deionized water.

A specific embodiment of the present invention also provides an application of the above-mentioned calcium silicate-calcium phosphate crystal phase composite material in the field of oral cavity, cosmetics and skin and mucous membrane repair.

The calcium silicate-calcium phosphate crystal phase composite material of the present invention and its application will be described in detail below with reference to specific examples.

Example 1

First, mix tetraethyl silicate (5.0g) and absolute ethanol (100mL) evenly, add it to 150ml of deionized water, then adjust the pH of the solution to 1-2 with nitric acid, stir magnetically at room temperature for 30 minutes, and then Dissolve 10.2g calcium oxalate completely in the solution to form component A. Mix diammonium hydrogen phosphate (3.2g) and calcium oxalate (5.3g) and dissolve them evenly in 150 ml of deionized water to form component B. After mixing component A and component B evenly, stir magnetically in a constant temperature water bath at 60°C for 30 minutes, and dry in a blast drying oven at 120°C for 12 hours. The dried powder was then placed in a muffle furnace, heated to 1400°C at a heating rate of 5°C/min, kept warm for 4 hours, and quenched in the air. The cooled product was mixed with absolute ethanol, ground in a ball mill at 200 rpm for 2 hours, and sieved to obtain the powder required for the experiment, which is calcium silicate-calcium phosphate crystal phase composite material.

Example 2

Mix diammonium hydrogen phosphate (3.2g), tetraethyl silicate (5.1g), calcium oxalate (16.2g) and absolute ethanol (120ML) in a molar ratio of 1:1:4.5:5 and add to 300 ML of deionized water, then adjust the pH of the solution to 1-2 with nitric acid, stir magnetically at room temperature for 60 minutes to form a white slurry, and dry in a blast drying oven at 120°C for 48 hours. The dried powder was then placed in a muffle furnace, heated to 1400°C at a heating rate of 5°C/min, kept warm for 4 hours, and quenched in the air. The cooled product was mixed with absolute ethanol, ground in a ball mill at 200 rpm for 2 hours, and sieved to obtain the powder required for the experiment, which is calcium silicate-calcium phosphate crystal phase composite material.

Example 3

First, mix tetraethyl silicate (5.6g) and absolute ethanol (130ML) evenly, add it to 150ml of deionized water, then adjust the pH of the solution to 1-2 with nitric acid to form _SiO2 sol, and then add 17.8g Calcium nitrate is completely dissolved in the solution to form component A. Mix 3.4g diammonium hydrogen phosphate and 8.9g calcium nitrate and dissolve evenly in 150ml deionized water to form component B. After mixing component A and component B evenly, stir magnetically in a constant temperature water bath at 60°C for 60 minutes to form a sol state, and then age at 60°C for 24 hours to form a wet gel. Dry in a forced air drying oven at 120°C for 48 hours. The xerogel was then placed in a muffle furnace, heated to 1400°C at a heating rate of 5°C/min, kept warm for 4 hours, and quenched in the air. The cooled product was mixed with absolute ethanol, ground in a ball mill at 200 rpm for 2 hours, and sieved to obtain the powder required for the experiment, which is calcium silicate-calcium phosphate crystal phase composite material.

Example 4

Mix 3.4g diammonium hydrogen phosphate, 5.3g tetraethyl silicate, 26.7g calcium nitrate and 120ML absolute ethanol, add them to 300ML deionized water, and then adjust the pH of the solution to 1-2 with nitric acid, 60°C Stir magnetically in a constant temperature water bath for 60 minutes to form a sol state, and then age at 60°C for 24 hours to form a wet gel. Dry in a forced air drying oven at 120°C for 48 hours. The xerogel was then placed in a muffle furnace, heated to 1400°C at a heating rate of 5°C/min, kept warm for 4 hours, and quenched in the air. The cooled product was mixed with absolute ethanol, ground in a ball mill at 200 rpm for 2 hours, and sieved to obtain the powder required for the experiment, which is calcium silicate-calcium phosphate crystal phase composite material.

Example 5

First, 4.2 g of tetraethyl silicate and 90 ml of anhydrous ethanol were mixed evenly and added to 150 ml of deionized water. Then, the pH of the solution was adjusted to 1-2 with hydrochloric acid. After magnetic stirring for 30 min at room temperature, 13.5 g of calcium oxalate was completely dissolved in the solution to form component A. 6.3 g of diammonium hydrogen phosphate and 12.3 g of calcium oxalate were mixed and evenly dissolved in 150 ml of deionized water to form component B. After component A and component B were mixed evenly, magnetic stirring was performed for 30 min in a 50 ° C constant temperature water bath, and dried at 110 ° C in a blast drying oven for 13 hours. Then, the dried powder was placed in a muffle furnace, heated to 1300 ° C at a heating rate of 6 ° C / min, kept warm for 3 hours, and rapidly cooled to room temperature in air. The cooled product was mixed with anhydrous ethanol and ground in a ball mill at 200 rpm for 2 hours, and the powder required for the experiment was sieved, which was the calcium silicate-calcium phosphate crystalline composite material. The composition and microstructure of the calcium silicate-calcium phosphate crystalline composite material obtained in this example are substantially the same as those of the calcium silicate-calcium phosphate crystalline composite material obtained in Example 1.

Example 6

First, 7.8g of tetraethyl silicate and 150ml of anhydrous ethanol were mixed evenly and added to 150ml of deionized water. Then, the pH of the solution was adjusted to 1-2 with nitric acid. After magnetic stirring for 30min at room temperature, 16.8g of calcium citrate was completely dissolved in the solution to form component A. 3.5g of diammonium hydrogen phosphate and 6.8g of calcium citrate were mixed and evenly dissolved in 150ml of deionized water to form component B. After component A and component B were mixed evenly, magnetic stirring was performed for 30min in a constant temperature water bath at 80℃, and dried at 130℃ in a blast drying oven for 11 hours. Then, the dried powder was placed in a muffle furnace, heated to 1200℃ at a heating rate of 10℃/min, kept warm for 6 hours, and rapidly cooled to room temperature in air. The cooled product was mixed with anhydrous ethanol and ground in a ball mill at 200rpm for 2h, and the powder required for the experiment was sieved, which was the calcium silicate-calcium phosphate crystalline composite material. The composition and microstructure of the calcium silicate-calcium phosphate crystalline composite material obtained in this example are substantially the same as those of the calcium silicate-calcium phosphate crystalline composite material obtained in Example 1.

Example 7

Mix 6.8g diammonium hydrogen phosphate, 3.2g tetraethyl silicate, 18.5g calcium oxalate and 90ML absolute ethanol, add them to 300ML deionized water, and then adjust the pH of the solution to 1-2 with nitric acid, at room temperature Stir magnetically for 50 minutes to form a white slurry, and dry it in a blast drying oven at 110°C for 40 hours. The dried powder was then placed in a muffle furnace, heated to 1300°C at a heating rate of 10°C/min, kept warm for 3 hours, and quenched in the air. The cooled product was mixed with absolute ethanol, ground in a ball mill at 200 rpm for 2 hours, and sieved to obtain the powder required for the experiment, which is calcium silicate-calcium phosphate crystal phase composite material. The calcium silicate-calcium phosphate crystal phase composite material obtained in this example has approximately the same composition and microstructure as the calcium silicate-calcium phosphate crystal phase composite material obtained in Example 2.

Example 8

Mix 3.7g diammonium hydrogen phosphate, 7.9g tetraethyl silicate, 16.8g calcium oxalate and 150ML absolute ethanol, add them to 300ML deionized water, and then adjust the pH of the solution to 1-2 with nitric acid, at room temperature Stir magnetically for 70 minutes to form a white slurry, and dry it in a forced air drying oven at 130°C for 36 hours. The dried powder was then placed in a muffle furnace, heated to 1200°C at a heating rate of 6°C/min, kept warm for 6 hours, and quenched in the air. The cooled product was mixed with absolute ethanol, ground in a ball mill at 200 rpm for 2 hours, and sieved to obtain the powder required for the experiment, which is calcium silicate-calcium phosphate crystal phase composite material. The calcium silicate-calcium phosphate crystal phase composite material obtained in this example has approximately the same composition and microstructure as the calcium silicate-calcium phosphate crystal phase composite material obtained in Example 2.

Comparative example 1

4510 bioactive glass (hereinafter referred to as bioglass) produced by Shanghai Nuosheng Medical Technology Co., Ltd.

The following tests were performed on the calcium silicate-calcium phosphate crystal phase composite materials in Examples 1-4.

(1)X-ray diffractometer (XRD)

The ground samples were characterized using XRD instrument.

(2) Infrared spectrum FTIR

Take about 2 mg of powder from the ground sample, add KBr powder, grind it, press it into tablets, and use an infrared spectrometer for characterization.

(3)Nano particle size

Take a trace amount of sample and put it into ultrapure water, disperse it evenly by ultrasonic, and test the particle size distribution of the sample on the machine. After measuring three times for a group of samples, take the average value.

(4) Specific surface area and pore size analysis (BET)

Take about 200mg of dry powder sample, degassing temperature is 150℃, duration is 5h, and test on the machine after degassing is completed.

(5) Scanning electron microscope (SEM): Take a trace sample, spray it with gold, and use SEM instrument to observe the morphology.

(6) Transmission electron microscope:

Take a trace amount of the sample and add it to absolute ethanol, ultrasonic for 2 hours to disperse it evenly, drop the dispersed suspension on the carbon film copper mesh, dry it naturally and put it on the machine to test the sample.

Among them, some test data are shown in Table 1:

Table 1

For ease of description, R-01 represents Embodiment 1, R-02 represents Embodiment 2, R-03 represents Embodiment 3, and R-04 represents Embodiment 4.

Figure 3 is the XRD pattern of the calcium silicate-calcium phosphate crystal phase composite material in Examples 1-4. It can be seen from the XRD pattern in Figure 1 that the phase composition of R-01 is mainly dicalcium silicate (C2S) , the phases of R-02 and R-04 are C2S and calcium oxide (CaO), R-03 may contain α-TCP and tricalcium silicate (C3S) phase components, in addition there is diffraction of calcium oxide and C2S peak. A typical amorphous structure is an amorphous amorphous material. The characteristic peaks in XRD are usually broad, which is caused by the disordered arrangement of atoms in the amorphous material.

Figure 4 is the FTIR spectrum of the calcium silicate-calcium phosphate crystal phase composite material in Examples 1-4. In the range of about 1000-1300 cm ^-1 , there is usually a strong peak, which represents the silicon-oxygen bond (Si- O) stretching vibration. The reflection peak at 1099cm ^-1 is Si-O stretching vibration; the reflection peak at 993cm ^-1 is PO stretching vibration peak; in the range of about 450-600cm ^-1 , there is usually a weak peak, which represents the silicon-oxygen bond. Bending vibration, this characteristic peak can be used to determine the existence and structure of silicon-oxygen bonds in the material.

Figure 5 is an SEM picture of the calcium silicate-calcium phosphate crystal phase composite material in Example 1-4, and Figure 6 is a particle size distribution diagram of the calcium silicate-calcium phosphate crystal phase composite material in Example 1-4. It can be seen from the SEM images that the microscopic morphology of each group of powders shows irregular flakes, and the average particle size of the samples is less than 5 μm. The particle size distribution of R-01 and R-02 is concentrated around 1100nm, the average particle size of R-03 is around 500nm, and the average particle size of R-04 is around 1000nm.

The following bioactivity tests are performed on the calcium silicate-calcium phosphate crystal phase composite materials in Examples 1-4 and the bioglass in Comparative Example 1:

The SBF solution is prepared in accordance with T/CSBM 0027-2022 standards and is ready for use. Add 15 ml of SBF solution into the polyethylene bottle. Accurately weigh 0.05g of each group of samples, pour it into the bottle, and fix it in a constant temperature shaker. Shake the polyethylene bottle at 37°C and 165 rpm. Each group of samples was shaken for 8h, 1d, 3d, and 5d respectively. After shaking for different times, the reacted SBF solution together with the sample powder was filtered through filter paper, and the filtered sample powder was rinsed with acetone to block the reaction. The powder was dried in an oven at 95°C for 1 hour, sealed in a sample bag, and stored in a desiccator for FTIR, XRD and SEM analysis. SBF solutions corresponding to different reaction times were sampled and stored in the refrigerator for ICP testing of the solutions.

Figure 7 is an XRD pattern of the bioglass in Comparative Example 1 after reacting in SBF solution for different times. Figure 8 is an SEM photo of the bioglass in Comparative Example 1 after being reacted in SBF solution for different times. It can be seen from the SEM image in Figure 8 that after the material was soaked in SBF for 3 days (3 days) and 5 days (5 days), the surface micromorphology of the material changed significantly. The different morphologies on the surface of the material may be the morphology of hydroxyapatite formed by mineralization, and the surface of the material provides a favorable nucleation site for the nucleation of calcium-phosphorus compounds. The XRD pattern in Figure 7 shows that the XRD pattern of the material after reacting in SBF solution for 3 days (3 days) has a diffuse apatite diffraction peak at around 2θ = 32°. This is due to the low levels of low energy generated on the surface of the material during the biomineralization process. Crystallinity of hydroxyapatite.

Figure 9 is an SEM photo of the calcium silicate-calcium phosphate crystal phase composite material in Example 1-4 after reacting in SBF solution for different times. It can be seen from the SEM image in Figure 9 that after each group of materials was soaked in SBF for 3 days (3 days) and 5 days (5 days), the surface micromorphology of the materials changed significantly. The different morphologies on the surface of the material may be the morphology of hydroxyapatite formed by mineralization. The reason for the formation of this morphology may be the diffusion of Ca ²⁺ , PO ₄ ^3- , OH ^- and CO ₃ ^2- plasma into the material. The microelectric layer on the surface promotes the nucleation of HCA, and the surface of the material provides a favorable nucleation site for the nucleation of calcium-phosphorus compounds.

Figure 10 is the XRD pattern of the calcium silicate-calcium phosphate crystal phase composite material in Example 1-4 after reacting in SBF solution for different times. As can be seen from Figure 10, the XRD pattern of each group of materials after reacting in SBF solution for 3 days (3 days) has a sharp diffraction peak at around 2θ = 32°. This is due to the low crystallinity hydroxyphosphorus generated on the surface of the materials during the biomineralization process. Caused by limestone, while the XRD patterns of the original samples R-01, R-02, R-03 and R-04 do not have this diffraction peak, indicating that the surface of the samples of R-01, R-02, R-03 and R-04 More hydroxyapatite is generated.

As shown in Figures 7-10, both the sample of this example and the control sample generated apatite mineralization to varying degrees. The calcium silicate-calcium phosphate crystal phase composite materials of Examples 1-4 of the present invention have the same remineralization ability as biological glass.

Soak test:

Equipment: Electronic balance with an accuracy of 0.01g; acidometer with a graduation value not greater than 0.02 pH units, equipped with glass electrodes and reference electrodes. Magnetic station equipped with a Teflon-coated stirring rotor.

Weigh (2.50±0.01) g of the calcium silicate-calcium phosphate crystalline composite materials in Examples 1-4 and the bioglass in Comparative Example 1 and place them in 47.5±0.01) g of distilled water, soak for 12 hours, and then test the pH value (measured with an acidity meter at 20° C. under magnetic stirring, and read the value after the acidity meter reading stabilizes). The data shown in the following table are obtained:

sample pH value/after soaking for 12 hours Comparative example 1 12.8 Example 1 8.7 Example 2 8.6 Example 3 8.2 Example 4 8.5

From the data in the above table, it can be seen that the calcium silicate-calcium phosphate crystalline composite materials prepared in Examples 1-4 of the present invention have a milder alkaline environment after immersion for 12 hours than the bioglass in Comparative Example 1, that is, the alkalinity is lower than that of the bioglass in Comparative Example 1. The calcium silicate-calcium phosphate crystalline composite materials of the present invention are applied to the field of skin and mucosal repair in the oral field, which reduces the impact on the progress and effect of tissue repair.

In summary, the inventor made extensive experiments and accidental discoveries, using metal alkoxide as raw material, and using calcium salt electrolyte salt to stabilize its gel state under acidic conditions; at the same time, phosphate groups were added to form silicic acid and phosphate groups. The composite phase of the group. Weakly crystalline calcium salt clusters are further compounded to slowly form a silicate-calcium phosphate precursor. By mixing and sintering the two, a calcium silicate-calcium phosphate crystal phase composite material was successfully prepared. By adjusting the proportion of the two, its organizational structure, biological activity and degradation properties can be adjusted, thereby preparing materials with appropriate properties according to actual needs. biomaterials.

It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and range of equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

In addition, it should be understood that although this specification is described in terms of implementations, not each implementation only contains an independent technical solution. This description of the specification is only for the sake of clarity, and those skilled in the art should take the specification as a whole. , the technical solutions in each embodiment can also be appropriately combined to form other implementations that can be understood by those skilled in the art.

Claims (10)

1. The calcium silicate-calcium phosphate crystalline phase composite material is characterized by being prepared by a preparation method A or a preparation method B;

the preparation method A comprises the following steps:

a1, obtaining a mixed system containing tetraethyl silicate, ethanol and water, regulating the pH value of the mixed system to 1-2 by using acid, and then adding calcium salt to obtain a first component;

a2, obtaining a mixed system containing phosphate, calcium salt and water to obtain a second component;

a3, uniformly mixing the first component and the second component, stirring at 50-80 ℃, drying at 110-130 ℃ for 11-13h, sintering, cooling, mixing with ethanol, grinding, and sieving to obtain the calcium silicate-calcium phosphate crystalline phase composite material;

the preparation method B comprises the following steps:

b1, obtaining a mixed system containing phosphate, tetraethyl silicate, ethanol, calcium salt and water, regulating the pH value of the mixed system to 1-2 by using acid, stirring, and drying at 110-130 ℃ for 36-48h;

and B2, sintering the dried product, cooling, mixing with ethanol, grinding, and sieving to obtain the calcium silicate-calcium phosphate crystalline phase composite material.

2. The calcium silicate-calcium phosphate crystalline phase composite material according to claim 1, wherein the phosphate is at least one of ammonium hydrogen phosphate, sodium hydrogen phosphate, and potassium dihydrogen phosphate; and/or the number of the groups of groups,

the calcium salt comprises at least one of water-soluble calcium oxalate, calcium nitrate, calcium citrate, calcium gluconate, calcium hypochlorite and calcium acetate; and/or the number of the groups of groups,

in the step A1 and/or the step B1, the acid for adjusting the pH value of the mixed system is any one of nitric acid, hydrochloric acid and acetic acid.

3. The calcium silicate-calcium phosphate crystalline phase composite material according to claim 1, characterized in that the sintering step in preparation method a and/or preparation method B specifically comprises:

heating the dried product to 1200-1400 ℃ at a heating rate of 5-10 ℃/min, and preserving the heat for 3-6 hours.

4. The calcium silicate-calcium phosphate crystalline phase composite material according to claim 1, wherein in step A1 of the preparation method a, the step of obtaining a mixed system containing tetraethyl silicate, ethanol and water comprises:

tetraethyl silicate and ethanol in the ratio of (0.1-0.4): 1, and adding water.

5. The calcium silicate-calcium phosphate crystalline phase composite material according to claim 1, wherein in step A1 of the preparation method a, the molar ratio of calcium salt to tetraethyl silicate is (0.5-1): 1.

6. The calcium silicate-calcium phosphate crystalline phase composite material according to claim 1, wherein in step A2 of the preparation method a, the step of obtaining a mixed system containing phosphate, calcium salt and water comprises:

phosphate and calcium salt were combined at 1: (1-1.5) and is dissolved in water.

7. The calcium silicate-calcium phosphate crystalline phase composite material according to claim 1, wherein in the preparation method a, the molar ratio of tetraethyl silicate in the first component to phosphate in the second component is (0.5-2): 1.

8. the calcium silicate-calcium phosphate crystalline phase composite material according to claim 1, wherein in the preparation method B,

the mole ratio of the phosphate to the tetraethyl silicate is (0.5-2): 1, a step of;

the molar ratio of the tetraethyl silicate to the ethanol is (0.1-0.4): 1

The molar ratio of the phosphate to the calcium salt is 1: (1-1.5).

9. The calcium silicate-calcium phosphate crystalline phase composite material according to claim 1, wherein the stirring treatment step in step B1 of the preparation method B is specifically:

when the calcium salt is weak electrolyte, magnetically stirring the mixed system with the pH value adjusted at room temperature for 50-70min to form white slurry; or alternatively, the first and second heat exchangers may be,

when the calcium salt is strong electrolyte, magnetically stirring the mixed system with the pH value regulated in a constant-temperature water bath at 50-80 ℃ for 50-70min to form a sol state, and then aging for 12-36h at 50-80 ℃ to form wet gel.

10. Use of a calcium silicate-calcium phosphate crystalline phase composite according to any one of claims 1-9 in the field of the oral cavity, in the field of cosmetics and in the field of skin mucosa repair.