A bone cement with near-infrared photothermal response and its preparation method

Abstract

This invention relates to a bone cement with near-infrared photothermal response and its preparation method, comprising the following steps: mixing cuttlebone bone powder with a zinc salt solution and adjusting the pH to alkaline; adding a phosphorus source solution and mixing evenly to obtain a mixed solution; subjecting the mixed solution to a hydrothermal reaction to obtain cuttlebone-based zinc-doped hydroxyapatite (ZHA); dispersing ZHA and dopamine hydrochloride in a Tris-HCl buffer solution with a pH of 8-9, and carrying out a polymerization reaction by stirring in the dark; subsequently, centrifuging, washing, and drying to obtain PZHA particles; mixing the PZHA particles evenly with calcium sulfate to obtain a mixed powder; then adding a chitosan quaternary ammonium salt solution to form a slurry; and curing the slurry to obtain bone cement with near-infrared photothermal response. The bone cement obtained by this invention can achieve highly efficient antibacterial and antioxidant effects under photothermal stimulation; and through the reinforcing effect of PZHA, the obtained bone cement possesses excellent mechanical properties and structural stability.

Description

Technical Field

[0001] This invention belongs to the field of biomedical materials and bone tissue engineering, specifically relating to a bone cement with near-infrared photothermal response function and its preparation method. Background Technology

[0002] Repairing large bone defects caused by severe trauma, tumor resection, or infection is a major clinical challenge. Bone cement can be injected into the defect area in liquid or semi-solid form to fill the gap, strengthen and stabilize the bone.

[0003] Currently, traditional bone cements (such as polymethyl methacrylate or calcium sulfate-based materials) can only provide physical support, but they are insufficient in addressing the harsh pathological microenvironment of bone defect areas (including the large accumulation of reactive oxygen species (ROS), severe inflammatory responses, and bacterial infections). They lack the ability to actively intervene in and regulate the bone immune microenvironment, and cannot effectively clear excess ROS at lesion sites or inhibit persistent inflammatory responses, often leading to suppressed osteoblast activity, fibrosis encapsulation, and tissue regeneration failure. Although existing modified bone cements attempt to incorporate antibacterial agents or active factors, single chemical or biological methods are insufficient to overcome the complex and dynamic in vivo inflammatory barrier; and they also suffer from poor mechanical properties. For example, traditional calcium sulfate (CSH) bone cement exhibits low mechanical strength and other physical defects during bone repair, making it difficult to meet the clinical need for long-term support.

[0004] Therefore, it is urgent to address the shortcomings of current bone cement, such as insufficient microenvironment regulation and poor mechanical properties. Summary of the Invention

[0005] The purpose of this invention is to overcome the above-mentioned technical deficiencies and provide a bone cement with near-infrared photothermal response function and its preparation method, thereby solving the technical problems of insufficient microenvironment regulation and poor mechanical properties of bone cement in the prior art.

[0006] To achieve the above-mentioned technical objectives, the technical solution provided by this invention is as follows: In a first aspect, the present invention provides a method for preparing bone cement with near-infrared photothermal response function, comprising the following steps: S1, mixing cuttlebone bone powder with zinc salt solution and adjusting the pH value to alkaline, adding phosphorus source solution and mixing evenly to obtain a mixed solution, and then reacting the mixed solution with hydrothermal reaction to obtain cuttlebone-based zinc hydroxyapatite ZHA; S2, dispersing ZHA and dopamine hydrochloride in Tris-HCl buffer solution with a pH value of 8-9, stirring in the dark to carry out a polymerization reaction, and then centrifuging, washing and drying to obtain PZHA particles; S3, mixing PZHA particles with calcium sulfate evenly to obtain a mixed powder, then adding chitosan quaternary ammonium salt solution to form a slurry, and then curing the slurry to obtain bone cement with near-infrared photothermal response function.

[0007] Secondly, the present invention provides a bone cement with near-infrared photothermal response function prepared by the above preparation method.

[0008] Compared with the prior art, the beneficial effects of the present invention include: This invention selects quaternary ammonium salt chitosan as the aqueous matrix, endowing the material with broad-spectrum antibacterial properties and excellent injection performance. Based on marine waste cuttlebone as a template, zinc-doped hydroxyapatite (ZHA) is synthesized in situ via a hydrothermal method, and polydopamine (PDA) is polymerized on the surface to form core-shell structured PZHA nanoparticles as a reinforcing phase, thereby constructing a micro-nano composite bone cement system that achieves multimodal synergy of physical, chemical, and biological processes. The resulting bone cement can achieve highly efficient antibacterial and antioxidant properties under photothermal stimulation. Furthermore, through the reinforcing effect of PZHA, the resulting bone cement possesses excellent mechanical properties and structural stability. Attached Figure Description

[0009] Figure 1 These are scanning electron microscope images of ZHA prepared in Example 1 of the present invention at different magnifications, wherein (a) has a scale bar of 500 nm and (b) has a scale bar of 200 nm. Figure 2 This is an elemental distribution diagram of the ZHA prepared in Example 1 of the present invention; Figure 3 Transmission electron microscope (TEM) images of PZHA prepared in Example 1 at different magnifications; Figure 4 The diagrams show the antioxidant properties and ROS scavenging capabilities of the ZHA and PZHA prepared in Example 1, respectively. Figure 5 Morphological images of PZHA / CSH-QCS bone cement prepared with different concentrations of PZHA. Figure 6 Mechanical property test results of PZHA / CSH-QCS bone cement prepared with different concentrations of PZHA; Figure 7 Photothermal properties of 1% PZHA / CSH-QCS bone cement; Figure 8 To assess the antibacterial properties of different bone cements. Detailed Implementation

[0010] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0011] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the invention, are intended to cover non-exclusive inclusion.

[0012] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0013] Currently, bone cement materials have the following defects in bone repair: (1) Insufficient microenvironment regulation: They lack the ability to actively intervene in and regulate the bone immune microenvironment, and cannot effectively remove the overloaded ROS at the lesion site or inhibit the continuous inflammatory response; (2) Poor mechanical properties: Traditional calcium sulfate (CSH) bone cement exhibits defects such as low mechanical strength during bone repair, and is difficult to meet the clinical long-term support needs.

[0014] Based on this, the present invention is established.

[0015] This invention provides a bone cement with near-infrared photothermal response and its preparation method. This bone cement is a biomimetic injectable "micro-nano composite" bone cement system (PZHA / CSH-QCS) with near-infrared (NIR) response and bone immune regulation functions. In this system, quaternary ammonium chitosan (QCS) is used as an aqueous matrix to endow the material with inherent broad-spectrum antibacterial activity and excellent injection performance. Simultaneously, marine biological waste (cuttlebone) is innovatively utilized as a natural mesoporous template and multiple trace elements (such as Ca) as a source of nutrients. 2+ Mg 2+ , Sr 2+ Zinc-doped hydroxyapatite (ZHA) was synthesized in situ via a hydrothermal method, and a layer of polydopamine (PDA) was further polymerized on its surface to construct a core-shell structured PZHA nano-reinforcing phase. This design not only macroscopically constructs a robust network similar to concrete, significantly compensating for the low mechanical strength of traditional calcium sulfate hemihydrate (CSH) bone cement, but also, under NIR irradiation, the PDA shell of the bone cement exhibits efficient photothermal conversion capabilities for mild photothermal therapy. Its abundant catechol groups also act as potent antioxidants, rapidly clearing excess ROS from the lesion site. As the bone cement undergoes steady-state degradation, the PZHA particles continuously release Zn... 2+Mg 2+ It contains key osteogenic metal ions and creates a multi-functional microenvironment regulatory center at the microscopic level.

[0016] In a first aspect, the present invention provides a method for preparing bone cement with near-infrared photothermal response function, comprising the following steps: S1, Preparation of cuttlebone-based zinc hydroxyapatite (ZHA): Cuttlebone bone powder is mixed with zinc salt solution and the pH value is adjusted to alkaline. Phosphorus source solution is added and mixed evenly to obtain a mixture. The mixture is then subjected to hydrothermal reaction to obtain cuttlebone-based zinc hydroxyapatite ZHA. S2, Preparation of PZHA-enhanced phase: ZHA and dopamine hydrochloride were dispersed in Tris-HCl buffer solution with a pH of 8-9 and polymerized by stirring in the dark. Afterwards, PZHA particles were obtained by centrifugation, washing and drying. S3, Bone cement preparation: PZHA particles and calcium sulfate are mixed evenly to obtain a mixed powder, and then chitosan quaternary ammonium salt solution is added to adjust it into bone cement with near-infrared photothermal response function.

[0017] In some embodiments, in step S1, the cuttlebone powder is obtained by crushing, soaking in hypochlorite, washing, drying and sieving cuttlebone.

[0018] Furthermore, the hypochlorite soaking treatment specifically includes immersing the pulverized cuttlebone powder in a 4-6% NaClO solution for 1.5-2.5 days. This invention uses hypochlorite soaking treatment to remove proteins and foreign matter.

[0019] Furthermore, the cleaning is carried out using distilled water; the drying is carried out at 35-45℃ for 40-60 hours.

[0020] In some embodiments, in step S1, the zinc salt solution is a zinc nitrate solution with a concentration of 0.3 to 0.7 mol / L; the ratio of cuttlebone powder to zinc salt solution is (3 to 7) g: 100 mL.

[0021] In some embodiments, in step S1, the phosphorus source solution is a diammonium hydrogen phosphate solution with a concentration of 0.1 to 0.3 mol / L; the ratio of cuttlebone powder to phosphorus source solution is (3 to 7) g: 100 mL.

[0022] In some embodiments, step S1, the preparation of the mixture specifically includes: mixing cuttlebone powder and zinc salt solution at 40-50°C and adjusting the pH value to 10-12; adding phosphorus source solution dropwise while maintaining the pH value at 10-12; and stirring for 10-90 minutes after the addition is complete to obtain the mixture. Sodium hydroxide solution can be used to adjust the pH value.

[0023] In some embodiments, in step S1, the hydrothermal reaction is carried out at 100–180°C for 12–48 hours.

[0024] In some embodiments, in step S2, the mass ratio of ZHA to dopamine hydrochloride is (0.5-2):(0.1-0.3).

[0025] In some embodiments, in step S2, the ratio of ZHA to Tris-HCl buffer is (0.5-2) g: 100 mL.

[0026] In some embodiments, in step S2, the polymerization reaction is carried out at 15–28°C with stirring in the dark for 20–28 hours.

[0027] In some embodiments, in step S3, the calcium sulfate is calcium sulfate hemihydrate.

[0028] In some embodiments, in step S3, PZHA particles account for 0.5 to 4% of the mass of the mixed powder.

[0029] In some embodiments, in step S3, the mass fraction of the chitosan quaternary ammonium salt solution is 1-3%; the mass ratio of the mixed powder to the chitosan quaternary ammonium salt solution is 1:(0.25-0.5).

[0030] Secondly, the present invention provides a bone cement with near-infrared photothermal response function prepared by the above preparation method.

[0031] The bone cement of this invention can be directly injected and used to prepare composite bone scaffolds.

[0032] The main mechanism of action and advantages of this invention are as follows: (1) In this invention, quaternary ammonium salt chitosan (QCS) is selected as the aqueous matrix to endow the material with broad-spectrum antibacterial properties and excellent injection performance; based on marine waste (cuttlebone) template, zinc-doped hydroxyapatite (ZHA) is synthesized in situ by hydrothermal method, and polydopamine (PDA) is polymerized on the surface to form core-shell structured nanoparticles as the reinforcing phase; thereby constructing a micro-nano composite bone cement system (PZHA / CSH-QCS) to achieve physical-chemical-biological multimodal synergy, and the resulting bone cement can achieve efficient antibacterial, antioxidant and immune regulation under photothermal stimulation; (2) This invention compensates for the low strength and insufficient antibacterial ability of CSH bone cement through the reinforcing effect of PZHA, thus possessing excellent mechanical properties and structural stability; through the reinforcing effect of Zn 2+Plasma release and immunomodulation significantly inhibit pro-inflammatory responses and promote vascular endothelial growth factor secretion, achieving deep coupling of angiogenesis, nerve innervation, and bone remodeling, thus providing immune enhancement and bone remodeling effects. It also has a dynamic microenvironment regulation function: under NIR irradiation, photothermal therapy dilates blood vessels, accelerates metabolism, and synergistically eliminates excess ROS in the inflammatory environment through the antioxidant function of PDA. This invention can also realize the medical high-value transformation of marine biological waste, which meets the requirements of environmental protection and sustainable development.

[0033] The present invention will be further described in detail below through specific embodiments. It should be noted that the embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application. Where specific techniques or conditions are not specified in the embodiments, they shall be performed in accordance with the techniques or conditions described in the literature in this field or in accordance with the product instructions. Reagents or instruments used that do not specify the manufacturer are all conventional products that can be obtained commercially.

[0034] Among them, chitosan quaternary ammonium salt was purchased from Aladdin, item number D1516230.

[0035] Example 1 A method for preparing bone cement with near-infrared photothermal response function includes the following steps: S1, Preparation of cuttlebone-based zinc hydroxyapatite (ZHA): S101, Pre-treated cuttlebone powder: Cuttlebone powder is prepared by high-speed pulverizer, and then the cuttlebone powder is soaked in 5% NaClO solution for 2 days to remove protein and foreign matter. After being washed with distilled water, it is dried at 40 ℃ for 48 hours. After being dried in an oven, it is sieved through a fine sieve for later use. S102: 5g of pretreated cuttlebone powder was mixed with 100ml of 0.5M zinc nitrate solution, the pH was adjusted to 10.5-11, and 100ml of 0.3M diammonium hydrogen phosphate solution was added dropwise. After the addition was completed, the mixture was stirred for 90 minutes, placed in a polytetrafluoroethylene liner, sealed in a hydrothermal reactor, and placed in a drying oven. The reactor was hydrothermally reacted at 120℃ for 12 hours. After the reaction was completed, the mixture was centrifuged and washed repeatedly with ethanol and deionized water more than three times. Finally, it was dried to obtain ZHA.

[0036] Preparation of S2, PZHA enhanced phase: 1 g ZHA was dispersed in 100 mL Tris-HCl buffer (10 mM, pH = 8.5), and 0.1 g dopamine hydrochloride (DA-HCl) was added. Polymerization was carried out by stirring in the dark at room temperature for 24 hours. PZHA particles were obtained by centrifugation, washing with ethanol and deionized water, and lyophilization.

[0037] S3, Preparation and molding of bone cement with near-infrared photothermal response function: 4.95g of calcium sulfate hemihydrate (CSH) and 0.05g of PZHA were uniformly mixed to obtain a mixed powder, wherein the content of PZHA was 1%. The mixed powder and liquid solution (QCS was dissolved in water at 2wt% to obtain QCS solution) were mixed at a mass ratio of 1:0.35 to obtain bone cement, denoted as 1% PZHA / CSH-QCS.

[0038] Example 2 Compared with Example 1, the only difference is that in step S3, 4.975g of calcium sulfate hemihydrate (CSH) and 0.025g of PZHA are uniformly mixed, and the content of PZHA is adjusted to 0.5%. The other steps and conditions are the same as in Example 1, and 0.5% PZHA / CSH-QCS is obtained.

[0039] Example 3 Compared with Example 1, the only difference is that in step S3, 4.9g of calcium sulfate hemihydrate (CSH) and 0.1g of PZHA are uniformly mixed, and the content of PZHA is adjusted to 2%. The other steps and conditions are the same as in Example 1, resulting in 2% PZHA / CSH-QCS.

[0040] Example 4 Compared with Example 1, the only difference is that in step S3, 4.8g of calcium sulfate hemihydrate (CSH) and 0.2g of PZHA are mixed evenly, and the content of PZHA is adjusted to 4%. The other steps and conditions are the same as in Example 1, resulting in 4% PZHA / CSH-QCS.

[0041] Comparative Example 1 Compared with Example 1, the only difference is that PZHA in step S3 is removed, while the other steps and conditions are the same as in Example 1, resulting in CSH-QCS.

[0042] Comparative Example 2 Compared with Example 1, the only difference is that QCS in step S3 is removed, while the other steps and conditions are the same as in Example 1, resulting in 1% PZHA / CSH.

[0043] Performance testing (1) The ZHA synthesized in Example 1 was analyzed by scanning electron microscopy and elemental distribution analysis, and the results are as follows: Figure 1 and Figure 2 As shown.

[0044] like Figure 1 Scanning electron microscopy (SEM) showed that the ZHA synthesized in Example 1 had a uniform petal-like morphology. Figure 2The elemental distribution map confirmed the uniform distribution of Ca, Mg, Zn and other important bioactive elements, which together created a microenvironment conducive to bone formation and angiogenesis.

[0045] (2) The PZHA synthesized in Example 1 was analyzed by transmission electron microscopy, and the results are as follows: Figure 3 As shown, it still has a petal-like structure and a layer of PDA was successfully loaded onto the ZHA surface.

[0046] (3) The antioxidant properties of ZHA and PZHA synthesized in Example 1 were evaluated by measuring their DPPH free radical scavenging rate. Specifically: Test conditions: ZHA and PZHA were placed in 100 uM / L DPPH ethanol solution to prepare a 0.1 g / mL dispersion. After the composite material was dispersed and incubated in the dark for 30 minutes, the absorbance at 517 nm was measured using a UV-Vis scanner, with ethanol as a blank control and pure DPPH solution as a control group.

[0047] like Figure 4 As shown, after adding different groups of samples, obvious color changes (from purple to yellow) can be observed, verifying that the PDA layer of PZHA compared to ZHA provides stronger antioxidant function and helps osteoblast growth.

[0048] (4) The bone cement synthesized in Examples 1-4 and Comparative Example 1 was injected into a mold and cured in a constant temperature oven at 37°C to obtain a cylindrical composite bone scaffold. Subsequent performance tests were conducted. The morphology of the obtained composite bone scaffold was observed and scanned by electron microscopy. The results are as follows: Figure 5 As shown, the color gradually darkens with the addition of PZHA, and excessive concentration makes the material uneven.

[0049] (5) The compressive strength of the composite bone scaffolds obtained by curing the bone cement synthesized in Examples 1-4 and Comparative Example 1 was tested. The test method was to place the fully cured and dried composite bone scaffold sample on an electronic universal testing machine and test the compressive strength at a loading rate of 1 mm / min. The results are as follows: Figure 6 As shown, comparing the mechanical properties of bone cement with different concentrations of PZHA, it was found that the bone scaffold with added PZHA had higher compressive strength than pure CSH, and the 1% PZHA / CSH-QCS bone scaffold had the highest compressive strength.

[0050] (6) Since the morphology and strength test results showed that 1% PZHA / CSH-QCS had the best performance, 1% PZHA / CSH-QCS was used for photothermal performance testing. The specific test conditions included: irradiation with 808 nm near-infrared laser and a power of 0.9 W / cm. 21.0W / cm 2 and 1.1W / cm 2 The surface center temperature of the sample was recorded using an infrared thermal imager. The temperatures of the 1% PZHA / CSH-QCS bone scaffold were recorded before irradiation (0 min), and at 1 min, 3 min, and 5 min after irradiation. The results are as follows: Figure 7 As shown.

[0051] like Figure 7 The 1% PZHA / CSH-QCS bone scaffold shown maintains photothermal performance at 41-43℃, which meets the current understanding that the mild photothermal temperature required for bone repair should be maintained at 41-43℃. Therefore, the bone cement prepared by this invention has good photothermal stability. Simultaneously, this composite bone scaffold exhibits excellent fluorescence response under 808 nm near-infrared laser irradiation, as shown in the figure, with clear fluorescence imaging and the fluorescence signal intensity gradually increasing with increasing excitation power. This confirms that this invention has successfully developed a bioactive bone cement composite material with good physicochemical properties and near-infrared response characteristics.

[0052] The above tests show that PZHA has a petal-like morphology and is composed of multiple elements. Its porous microstructure is closer to that of natural bone tissue, which is more conducive to cell migration, attachment, and proliferation. It also contains various bone-forming bioactive factors (Zn...). 2+ Mg 2+ Therefore, PZHA not only has advantages in promoting cell adhesion, proliferation, differentiation and bone regeneration, but also has photothermal properties and antioxidant capacity, thereby enhancing its potential in fracture repair applications.

[0053] (7) Since the morphology and strength test results showed that 1% PZHA / CSH-QCS had the best performance, the antibacterial experiment was only conducted on the 1% PZHA concentration. The specific test method was as follows: the antibacterial activity of calcium sulfate hemihydrate (CSH), Comparative Example 2 (1% PZHA / CSH), and Example 1 (1% PZHA / CSH-QCS) against Staphylococcus aureus and Escherichia coli were tested separately. After activation, the two strains were cultured under suitable conditions for 24 h for later use. An appropriate amount of the prepared bone scaffold material (Φ10 mm × 2.5 mm) was placed in a 24-well plate and transferred to a clean bench for sterilization by ultraviolet irradiation. 100 μL of bacterial suspension (prepared in PBS, concentration of 106 CFU / mL) was added to the surface of the material, and then the 24-well plate was placed in a constant temperature incubator at 37 ℃ for 2 h. Then, 1 mL of sterile PBS was added to each well to resuspend the bacteria. Subsequently, 50 µL of the above bacterial suspension was taken and evenly spread on a solid agar plate. After coating, the plates were placed in a 37 ℃ incubator for 18-24 h and then observed and photographed.

[0054] The results are as follows Figure 8 As shown, the antibacterial properties of bone cement against Staphylococcus aureus and Escherichia coli were observed. It was found that 1% PZHA / CSH in Comparative Example 2 had a certain antibacterial effect, indicating that increasing PZHA is beneficial to improving antibacterial properties. However, the effect was not as good as that of 1% PZHA / CSH-QCS obtained in Example 1, which showed good antibacterial properties with an antibacterial rate of up to 99%. This indicates that the present invention significantly improves the antibacterial properties of the material by compounding QCS with PZHA.

[0055] In summary, this invention utilizes marine waste to provide a natural mesoporous template and multiple trace elements (Ca). 2+ Mg 2+ , Sr 2 + (etc.) to construct a bone cement system with a biomimetic micro-nano structure-concrete-like robust network; the PDA shell has efficient photothermal conversion (implementing MPTT) and strong ROS scavenging function, and the PZHA component continuously releases osteogenic metal ions to form a multi-effect regulatory center; through the spatiotemporal synergy of photothermal stimulation, ROS scavenging and bioactive ions, macrophage polarization is precisely regulated and the bone immune microenvironment is reshaped.

[0056] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for preparing bone cement with near-infrared photothermal response function, characterized in that, Includes the following steps: S1, Cuttlebone powder is mixed with zinc salt solution and the pH value is adjusted to alkaline. Phosphorus source solution is added and mixed evenly to obtain a mixture. The mixture is then subjected to hydrothermal reaction to obtain cuttlebone-based zinc hydroxyapatite ZHA. S2, ZHA and dopamine hydrochloride were dispersed in Tris-HCl buffer solution with a pH of 8-9 and polymerized by stirring in the dark. Afterwards, PZHA particles were obtained by centrifugation, washing and drying. S3, PZHA particles are mixed with calcium sulfate to obtain a mixed powder, and then chitosan quaternary ammonium salt solution is added to form a slurry. The slurry is then cured to obtain bone cement with near-infrared photothermal response function.

2. The method for preparing bone cement with near-infrared photothermal response function according to claim 1, characterized in that, In step S1, the cuttlebone powder is obtained by crushing cuttlebone, soaking in hypochlorite, washing, drying and sieving.

3. The method for preparing bone cement with near-infrared photothermal response function according to claim 2, characterized in that, The hypochlorite soaking treatment specifically includes: immersing the pulverized cuttlebone powder in a 4-6% NaClO solution for 1.5-2.5 days; The cleaning was performed using distilled water. The drying process involves drying at 35–45°C for 40–60 hours.

4. The method for preparing bone cement with near-infrared photothermal response function according to claim 1, characterized in that, In step S1, the zinc salt solution is a zinc nitrate solution with a concentration of 0.3-0.7 mol / L; the ratio of cuttlebone powder to zinc salt solution is (3-7) g: 100 mL; The phosphorus source solution is a diammonium hydrogen phosphate solution with a concentration of 0.1-0.3 mol / L; the ratio of cuttlebone powder to phosphorus source solution is (3-7) g: 100 mL.

5. The method for preparing bone cement with near-infrared photothermal response function according to claim 1, characterized in that, In step S1, the preparation steps of the mixture specifically include: mixing cuttlebone powder and zinc salt solution at 40-50℃ and adjusting the pH value to 10-12; adding phosphorus source solution dropwise while maintaining the pH value at 10-12; and stirring for 10-90 minutes after the addition is completed to obtain the mixture. The hydrothermal reaction is carried out at 100–180°C for 12–48 hours.

6. The method for preparing bone cement with near-infrared photothermal response function according to claim 1, characterized in that, In step S2, the mass ratio of ZHA to dopamine hydrochloride is (0.5-2):(0.1-0.3). The ratio of ZHA to Tris-HCl buffer is (0.5-2) g: 100 mL.

7. The method for preparing bone cement with near-infrared photothermal response function according to claim 1, characterized in that, In step S2, the polymerization reaction is carried out at 15–28°C with stirring in the dark for 20–28 hours.

8. The method for preparing bone cement with near-infrared photothermal response function according to claim 1, characterized in that, In step S3, the calcium sulfate is calcium sulfate hemihydrate; The PZHA particles account for 0.5 to 4% of the mass of the mixed powder.

9. The method for preparing bone cement with near-infrared photothermal response function according to claim 1, characterized in that, In step S3, the mass fraction of the chitosan quaternary ammonium salt solution is 1-3%; the mass ratio of the mixed powder to the chitosan quaternary ammonium salt solution is 1:(0.25-0.5).

10. Bone cement with near-infrared photothermal response function prepared by the preparation method according to any one of claims 1-9.

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