Clustered spherical zinc silicate microsphere and preparation method therefor

Abstract

The present invention provides a clustered spherical zinc silicate microsphere and a preparation method therefor. Clustered spherical zinc silicate with uniform size and complete assembly is obtained by a one-step hydrothermal reaction under an alkaline condition by using a surfactant as a template agent, a soluble zinc salt as a zinc source, and organic silicon or soluble silicate as a silicon source. The clustered spherical zinc silicate microsphere in the present invention is a biological, medical and adsorption material with great potential, is expected to be widely applied in the fields of wound infection, bone repair, drug loading, dye-containing wastewater treatment and the like, and is suitable for further industrial application.

Description

Clustered spherical zinc silicate microspheres and preparation method thereof Technical Field

[0001] The present invention relates to the technical field of inorganic chemical materials, and in particular to clustered spherical zinc silicate microspheres and a preparation method thereof. Background Art

[0002] Zinc silicate, with the chemical formula Zn2SiO4, is a type of orthosilicate containing a limited number of siloxy groups. Due to its excellent physical and chemical properties, including relatively stable chemical properties, good chemical adaptability, and strong moisture resistance, zinc silicate is widely used in coatings, glazes, fluorescent materials, paints, coatings, catalyst supports, radar technology, and mesoporous molecular sieves. However, its application in biology and medicine is relatively limited.

[0003] In fact, both Zn and Si in zinc silicate are biosafety elements with excellent biological functions. Zn is an essential trace element for the human body. Zn ions can inhibit bacterial activity by inhibiting glycolysis and transmembrane proton translocation. In addition to its excellent antibacterial activity, Zn can promote osteogenesis by promoting osteoclast apoptosis and significantly enhance stem cell proliferation and osteogenic differentiation. Si's role in promoting bone mineralization has been demonstrated as early as the 1970s. With the extension of human lifespan, Si can significantly enhance the osteogenic activity of scaffolds and regulate their degradation rate. In addition to its osteogenic activity, studies have shown that Si can also promote angiogenesis by promoting the expression of angiogenesis-related genes such as VEGF and HIF-α. Therefore, zinc silicate may have broad application prospects in the biological and medical fields. Furthermore, silicates can be used to adsorb and remove organic pollutants and precious metal ions from wastewater and serve as nanoreactors and biosensors.

[0004] At present, zinc silicate with different morphologies such as rods, needles, spindles and spheres can be prepared through sol-gel method, supercritical water oxidation technology, spray pyrolysis method, solid-phase synthesis method and hydrothermal synthesis method. However, these morphologies obtained have the problem of insufficient uniformity, which limits the performance of zinc silicate. In addition, the preparation process is relatively complicated, which restricts the further application of zinc silicate. Summary of the Invention

[0005] The present invention aims to address the deficiencies of the prior art and provide a clustered spherical zinc silicate microsphere and a preparation method thereof. A hydrothermal synthesis method is adopted, in which a surfactant is added during the synthesis process to provide nucleation sites and dispersed particles, and the pH of the reaction system is controlled to obtain clustered spherical zinc silicate microspheres, thereby achieving better adsorption and drug loading functions of zinc silicate.

[0006] The first aspect of the present invention relates to clustered spherical zinc silicate microspheres, which are obtained by a one-step hydrothermal reaction under alkaline conditions using a surfactant as a template, a soluble zinc salt solution as a zinc source, and an organosilicon or a soluble silicate solution as a silicon source. The zinc silicate microspheres are clustered and assembled from needles, and have a uniform particle size distribution.

[0007] As an optional embodiment, the diameter of the clustered spherical zinc silicate microspheres is 2 to 10 μm, and the pore size is 2 to 100 nm.

[0008] The second aspect of the present invention relates to a method for preparing the aforementioned clustered spherical zinc silicate microspheres, comprising the following specific steps:

[0009] S1. Add a surfactant into deionized water and dissolve it fully and evenly to obtain a surfactant solution;

[0010] S2, adding a silicon source to the surfactant solution, adding a zinc source after sufficient reaction, and stirring evenly to obtain a first mixed solution;

[0011] S3, adjusting the pH of the first mixed solution to a strongly alkaline state to obtain a second mixed solution;

[0012] S4, placing the second mixed solution in a hydrothermal reactor for hydrothermal reaction, and cooling to room temperature after the reaction to obtain a hydrothermal product;

[0013] S5. Washing and drying the hydrothermal product in sequence to obtain clustered spherical zinc silicate microspheres.

[0014] As an optional embodiment, in step S1, the mass percentage of the surfactant to the deionized water is (0:100) to (5:95).

[0015] As an optional embodiment, the surfactant is a cationic surfactant or an anionic surfactant.

[0016] As an optional embodiment, the cationic surfactant includes cetyltrimethylammonium bromide (CTAB) and / or dodecyltrimethylammonium chloride (DTAC); the anionic surfactant includes sodium dodecyl sulfate (SDS) and / or sodium dodecylbenzenesulfonate (SDBS).

[0017] As an optional embodiment, in the first mixed solution, the concentration of the silicon source is 1×10 -5 ~9×10 -5 mol / L, the concentration of zinc source is 2×10 -5 ~1.8×10 -4 mol / L.

[0018] As an optional embodiment, the silicon source is organosilicon or a soluble silicon salt solution, and the zinc source is a soluble zinc salt solution; wherein the organosilicon includes ethyl orthosilicate, the soluble silicon salt includes sodium silicate or potassium silicate, and the soluble zinc salt includes zinc nitrate or zinc acetate.

[0019] As an optional embodiment, in step S3, the pH value of the first mixed solution is adjusted to 10-12 by adding alkaline solution.

[0020] As an optional embodiment, in step S4, the temperature of the hydrothermal reaction is 120° C. to 240° C., and the reaction time is 6 h to 48 h.

[0021] Compared with the prior art, the present invention has the following significant beneficial effects:

[0022] The clustered spherical zinc silicate microspheres of the present invention are synthesized by adding a surfactant to provide nucleation sites and dispersed particles, and by regulating the pH of the reaction system to control the morphology of the powder, thereby obtaining clustered spherical zinc silicate microspheres with complete assembly, uniform morphology, and uniform dispersion, thereby achieving better adsorption and drug loading functions of zinc silicate.

[0023] The invention adopts a one-step method to synthesize clustered spherical zinc silicate microspheres. The preparation method is simple to operate, low in cost, low in energy consumption, and controllable in process, and has application prospects for industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] FIG1 is a SEM image of the product of Example 1 of the present invention.

[0025] FIG2 is a SEM image of the product of Comparative Example 1 of the present invention.

[0026] FIG3 is an XRD pattern of the product of Example 1 of the present invention. DETAILED DESCRIPTION

[0027] In order to better understand the technical content of the present invention, specific embodiments are given below in conjunction with the accompanying drawings.

[0028] Various aspects of the present invention are described in this disclosure with reference to the accompanying drawings, in which a number of illustrative embodiments are shown. The embodiments of the present disclosure are not necessarily intended to be comprehensive. It should be understood that the various concepts and embodiments described above, as well as those described in more detail below, can be implemented in any of a number of ways.

[0029] In an exemplary embodiment of the present invention, clustered spherical zinc silicate microspheres are provided. The zinc silicate microspheres are obtained by a one-step hydrothermal reaction under alkaline conditions using a surfactant as a template, a soluble zinc salt solution as a zinc source, and an organosilicon or a soluble silicate solution as a silicon source. The zinc silicate microspheres are clustered and assembled from needles, and have a uniform particle size distribution.

[0030] As an optional embodiment, the diameter of the clustered spherical zinc silicate microspheres is 2 to 10 μm, and the pore size is 2 to 100 nm.

[0031] In another exemplary embodiment of the present invention, a method for preparing the aforementioned clustered spherical zinc silicate microspheres is provided, comprising the following specific steps:

[0032] S1. Add a surfactant into deionized water and dissolve it fully and evenly to obtain a surfactant solution;

[0033] S2, adding a silicon source to the surfactant solution, adding a zinc source after sufficient reaction, and stirring evenly to obtain a first mixed solution;

[0034] S3, adjusting the pH of the first mixed solution to a strongly alkaline state to obtain a second mixed solution;

[0035] S4, placing the second mixed solution in a hydrothermal reactor for hydrothermal reaction, and cooling to room temperature after the reaction to obtain a hydrothermal product;

[0036] S5. Washing and drying the hydrothermal product in sequence to obtain clustered spherical zinc silicate microspheres.

[0037] As an optional embodiment, in step S1, the mass percentage of the surfactant to the deionized water is (0:100) to (5:95), and particularly preferably (1:99) to (3:97).

[0038] As an optional embodiment, the surfactant is a cationic surfactant or an anionic surfactant.

[0039] As an optional embodiment, the cationic surfactant includes cetyltrimethylammonium bromide (CTAB) and / or dodecyltrimethylammonium chloride (DTAC); the anionic surfactant includes sodium dodecyl sulfate (SDS) and / or sodium dodecylbenzenesulfonate (SDBS).

[0040] In another preferred embodiment, the surfactant is cetyltrimethylammonium bromide (CTAB).

[0041] As an optional embodiment, in the first mixed solution, the concentration of the silicon source is 1×10 -5 ~9×10 -5 mol / L, particularly preferably 2×10 -5 ~6×10 -5 mol / L; the concentration of zinc source is 2×10 -5 ~1.8×10 -4 mol / L, particularly preferably 4×10 -5 ~1.2×10-4 mol / L.

[0042] As an optional embodiment, the silicon source is organosilicon or a soluble silicon salt solution, and the zinc source is a soluble zinc salt solution; wherein the organosilicon includes ethyl orthosilicate, the soluble silicon salt includes sodium silicate or potassium silicate, and the soluble zinc salt includes zinc nitrate or zinc acetate.

[0043] As an optional embodiment, in step S3, the pH value of the first mixed solution is adjusted to 10-12 by adding alkaline solution.

[0044] In another preferred embodiment, the pH value of the first mixed solution is adjusted to 10-12 by dropwise addition of NH 3 ·H 2 O.

[0045] In another preferred embodiment, the amount of alkali solution added is 0.5 to 5 mL, and the concentration is 6 mol / L, particularly preferably 1 to 3 mL.

[0046] As an optional embodiment, in step S4, the temperature of the hydrothermal reaction is 120° C. to 240° C., and preferably 150° C. to 220° C.; the reaction time is 6 h to 48 h, and preferably 12 h to 30 h.

[0047] In a preferred embodiment, the temperature of drying the hydrothermal product after washing is 60°C to 100°C.

[0048] The preparation method of the present invention has the advantages of low cost, simple operation, controllable process, mild reaction conditions, low energy consumption, and stable products. The obtained clustered spherical zinc silicate microspheres are a promising biological, medical and adsorption material, and are expected to be widely used in the fields of wound infection, bone repair, drug loading and dye-containing wastewater treatment. They are particularly suitable for use as hard tissue repair materials, and can be used as bone tissue repair, filling and dental repair materials, and are suitable for further industrial application.

[0049] For better understanding, the present invention is further described below with reference to specific examples, but the preparation method is not limited thereto, and the content of the present invention is not limited thereto.

[0050] Unless otherwise specified, the raw materials in the following examples were purchased from commercial sources.

[0051] Example 1

[0052] (1) Weigh 0.3 g of CTAB and add it to 20 mL of deionized water until fully dissolved.

[0053] (2) adding 1 mmol of ethyl orthosilicate dropwise to the solution of step (1) and stirring evenly;

[0054] (3) 10 mL of 0.2 mmol / L zinc nitrate solution was added dropwise to the solution in step (2) to allow for sufficient reaction;

[0055] (4) Add 1 mL of 6 mol / L NH3·H2O dropwise to the solution in step (3) to obtain a white suspension with a pH of about 10 to 12;

[0056] (5) The suspension obtained in step (4) was transferred to a hydrothermal reactor, reacted at 180° C. for 24 hours, and then cooled naturally to obtain a hydrothermal product;

[0057] (6) The hydrothermal product obtained in step (5) was washed three times with water and three times with anhydrous ethanol, and then dried in an oven at 60° C. to obtain clustered spherical zinc silicate.

[0058] Example 2

[0059] The difference between Example 2 and Example 1 is that the amount of CTAB used is 0.1 g.

[0060] Example 3

[0061] The difference between Example 3 and Example 1 is that the amount of CTAB used is 0.2 g.

[0062] Example 4

[0063] The difference between Example 4 and Example 1 is that the amount of CTAB used is 0.4 g.

[0064] Example 5

[0065] The difference between Example 5 and Example 1 is that the hydrothermal reaction time is 12 hours.

[0066] Comparative Example 1

[0067] The difference between the comparative example and Example 1 is that the amount of CTAB used is 0 g.

[0068] SEM testing

[0069] The products obtained in Example 1 and Comparative Example 1 were subjected to SEM testing, and the results are shown in FIG1 and FIG2 .

[0070] As can be seen from the figure, the Zn2SiO4 of the present invention has a clustered spherical morphology assembled from needles (Figure 1), with a uniform particle size distribution of 1 to 5 μm and good dispersibility; while the Zn2SiO4 prepared in the comparative example is a small cluster assembled from rods, which is not spherical and does not have drug loading and adsorption functions (Figure 2).

[0071] XRD test

[0072] [Corrected 09.12.2024 according to Rule 91] The product obtained in Example 1 was subjected to XRD test, and the results are shown in Figure 3.

[0073] As can be seen from the figure, the XRD pattern of the clustered spherical Zn2SiO4 matches well with the XRD standard card number PDF#85-1387, indicating that the obtained product is Zn2SiO4, and the product has good crystallinity and high purity.

[0074] As can be seen from the above, the present invention successfully obtains clustered spherical zinc silicate microspheres with uniform size and complete assembly through a one-step hydrothermal reaction.

[0075] While the present invention has been disclosed above with reference to preferred embodiments, this is not intended to limit the present invention. Persons skilled in the art will readily appreciate that various modifications and variations can be made without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the claims.

Claims

1. A clustered spherical zinc silicate microsphere, characterized in that: A surfactant is used as a template, a soluble zinc salt solution is used as a zinc source, and an organic silicon or a soluble silicate solution is used as a silicon source. Zinc silicate microspheres are obtained through a one-step hydrothermal reaction under alkaline conditions; wherein the zinc silicate microspheres are clustered balls assembled from needles, and the particle size distribution is uniform.

2. The clustered spherical zinc silicate microspheres according to claim 1, characterized in that: The diameter of the clustered spherical zinc silicate microspheres is 2 to 10 μm, and the pore size is 2 to 100 nm.

3. A method for preparing clustered spherical zinc silicate microspheres according to any one of claims 1 to 2, characterized in that: The specific steps include: S1. Add a surfactant into deionized water and fully dissolve it to obtain a surfactant solution; S2, adding a silicon source to the surfactant solution, adding a zinc source after sufficient reaction, stirring evenly, to obtain a first mixed solution; S3, adjusting the pH of the first mixed solution to a strong alkaline state to obtain a second mixed solution; S4, placing the second mixed solution in a hydrothermal reactor for hydrothermal reaction, and cooling to room temperature after the reaction to obtain a hydrothermal product; S5. Washing and drying the hydrothermal product in sequence to obtain clustered spherical zinc silicate microspheres.

4. The preparation method according to claim 3, characterized in that: In the step S1, the mass percentage of the surfactant to the deionized water is (0:100) to (5:95).

5. The preparation method according to claim 3, characterized in that: The surfactant is a cationic surfactant or an anionic surfactant.

6. The preparation method according to claim 3, characterized in that: The cationic surfactant includes hexadecyltrimethylammonium bromide (CTAB) and / or dodecyltrimethylammonium chloride (DTAC); the anionic surfactant includes sodium dodecyl sulfate (SDS) and / or sodium dodecylbenzene sulfonate (SDBS).

7. The preparation method according to claim 3, characterized in that: In the first mixed solution, the concentration of the silicon source is 1×10 -5 ~9×10 -5 mol / L, the concentration of zinc source is 2×10 -5 ~1.8×10 -4 mol / L.

8. The preparation method according to claim 3, characterized in that: The silicon source is organic silicon or a soluble silicon salt solution, and the zinc source is a soluble zinc salt solution; wherein the organic silicon includes ethyl orthosilicate, the soluble silicon salt includes sodium silicate or potassium silicate, and the soluble zinc salt includes zinc nitrate or zinc acetate.

9. The preparation method according to claim 3, characterized in that: In the step S3, the pH value of the first mixed solution is adjusted to 10-12 by adding alkaline solution.

10. The preparation method according to claim 3, characterized in that: In step S4, the temperature of the hydrothermal reaction is 120° C. to 240° C., and the reaction time is 6 h to 48 h.

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