Bone filler containing magnetic calcium salt and preparation method thereof

Abstract

The present invention relates to a bone filler containing a magnetic calcium salt and a preparation method. The bone filler is in block form and is prepared by mixing and solidifying a powder and a liquid in a ratio of 2:1 g / mL. The powder components and their weight percentages are: 61.5-81.7% calcium sulfate and 18.3-38.5% magnetic calcium salt. The liquid is a sodium carboxymethyl cellulose solution containing disodium hydrogen phosphate, with the weight percentage of disodium hydrogen phosphate being 0.16-2.52% and the weight percentage of sodium carboxymethyl cellulose being 1.15-4.25%. The bone filler containing a magnetic calcium salt has the advantages of a moderate magnetothermal heating rate, resistance to water disintegration, and biodegradable absorption.

Description

Technical Field

[0001] The invention belongs to the field of biomedical materials, and in particular relates to a bone filler containing magnetic calcium salt and a preparation method thereof. Background Art

[0002] When bone defects reach a critical size, bone grafting is often required. Currently, bone repair materials commonly used are bone cements. These materials, typically formed by blending solid and liquid phases and then solidifying, are self-setting biomaterials. They can be shaped into any desired shape before solidification and are injectable, making them minimally invasive and highly convenient to manipulate. This makes them a popular choice among surgeons and a widely used orthopedic biomaterial. An ideal bone cement should exhibit excellent biocompatibility, promote new bone formation, and be fully biodegradable and resorbable. Its mechanical properties should be similar to or even superior to those of natural bone. The most commonly used bone cement materials are inorganic bone cements such as calcium phosphate or calcium sulfate. While calcium phosphate bone cements can be degraded and resorbed after implantation, they are prone to disintegration. For bone defects caused by bone tumors or bone metastases of malignant tumors, surgical resection of the tumor must be supplemented with other postoperative treatments such as chemotherapy and radiotherapy. Inorganic bone cements such as calcium phosphate also lack supportive follow-up treatment options. Many scholars have used bone repair materials with magnetic functional phases to repair bone tissue during bone tumor surgery and to assist in the treatment of bone tumors with magnetic hyperthermia to prevent tumor recurrence and metastasis, which has become a new treatment method in the field of bone tumor treatment. The most commonly used magnetic material is Fe3O4 magnetic powder, such as YMatsumine. Calcium phosphate bone cement is used as the matrix, and Fe3O4 is introduced into it to prepare magnetic bone cement. After the material is implanted into the bone, the surface temperature of the cortical bone can reach 40°C within 2 minutes under a 1.5MHz magnetic field. He Shuli and others have also invented high-heat-yielding magnetic bone cements with cobalt ferrite, manganese ferrite, and zinc ferrite as magnetic functional phases. However, bone filling materials or bone cements with added magnetic ferroferric oxide have the problem of too fast a heating rate, and the extreme temperature can reach 500°C, which poses a risk of burning other tissues. In addition, the added bone grafting material has no antibacterial properties, and antibiotics need to be added separately or antibacterial elements such as silver need to be introduced to assist in antibacterial treatment. Summary of the Invention

[0003] In view of the shortcomings of the prior art, the present invention provides a bone filler containing magnetic calcium salt, which has a moderate magnetothermal heating rate, is resistant to water disintegration, and is degradable and absorbable, and a preparation method thereof.

[0004] One of the above-mentioned purposes of the present invention is achieved by the following technical solutions:

[0005] A bone filler containing magnetic calcium salt is in block form and is prepared by mixing and solidifying a powder and a liquid in a ratio of 2:1 g / mL. The powder components and their mass percentages are: 61.5-81.7% calcium sulfate and 18.3-38.5% magnetic calcium salt. The liquid is a sodium carboxymethyl cellulose solution containing disodium hydrogen phosphate, with the mass percentage of the disodium hydrogen phosphate being 0.16-2.52% and the mass percentage of the sodium carboxymethyl cellulose being 1.15-4.25%.

[0006] Moreover, the magnetic calcium salt is a calcium oxide / ferroferric oxide complex, wherein the mass percentage of calcium oxide in the magnetic calcium salt is 22-47%, and the mass percentage of ferroferric oxide in the magnetic calcium salt is 53-78%.

[0007] Moreover, the particle size distribution of magnetic calcium salts ranges from 2.7 to 83 μm;

[0008] Moreover, the calcium sulfate is a mixture of calcium sulfate hemihydrate and calcium sulfate dihydrate, wherein the mass percentage of calcium sulfate hemihydrate is 70-95% and the rest is calcium sulfate dihydrate.

[0009] The second object of the present invention is achieved by the following technical solutions

[0010] A method for preparing the above-mentioned bone filler containing magnetic calcium salt comprises the following steps:

[0011] Step 1, preparing a sodium carboxymethyl cellulose solution with a mass percentage of 3.28-6.52%, and then adding iron powder to the sodium carboxymethyl cellulose solution to prepare an iron powder suspension, wherein the mass percentage of iron powder to sodium carboxymethyl cellulose solution is (0.35-1.11):1;

[0012] Step 2, preparing a sodium hydroxide solution with a mass percentage of 10.7-47.3%, and a calcium chloride solution with a mass percentage of 14.2-42.5%;

[0013] Step 3, adding the iron powder suspension prepared in step 1 to the sodium hydroxide solution prepared in step 2, with the volume ratio of the two being 1:3; then adding the calcium chloride solution prepared in step 2 to the iron powder / sodium carboxymethyl cellulose / sodium hydroxide solution at a rate of 1.5-24 mL / min, with the volume ratio of the calcium chloride solution to the sodium hydroxide solution being 1:2;

[0014] Step 4: Continue stirring and reacting for 20-60 minutes to obtain an iron / calcium hydroxide suspension, and filter and wash to obtain an iron / calcium hydroxide precipitate;

[0015] Step 5: calcining the precipitate at 530-590° C. for 15-120 min, transferring it to a dryer and cooling it to room temperature; crushing and grinding it to obtain a magnetic calcium salt with controllable particle size and morphology;

[0016] Step 6: uniformly mixing a predetermined amount of magnetic calcium salt and a predetermined amount of calcium sulfate to obtain a powder;

[0017] Step 7, preparing a sodium carboxymethyl cellulose solution containing disodium hydrogen phosphate, wherein the mass percentage of disodium hydrogen phosphate is 0.16-2.52%, and the mass percentage of sodium carboxymethyl cellulose is 1.15-4.25%;

[0018] Step 8: Add the mixed powder to the liquid in a ratio of 2:1g / mL and stir.

[0019] After 10 to 60 seconds, apply it to the mold with the reserved hole, solidify it for 10 to 20 minutes, and then demould it to obtain the bone filler containing magnetic calcium salt.

[0020] The advantages and positive effects of the present invention are:

[0021] 1. The present invention prepares a calcium hydroxide / iron complex by a suspension emulsion dispersion method, solving the problem of uneven mixing caused by directly adding iron or iron oxide to calcium salt powder. The viscous liquid of sodium carboxymethyl cellulose is equivalent to an emulsion, which enhances the surface tension of water, hinders the speed at which calcium ions and hydroxide ions combine to form a precipitate, and forms regular micron particles based on iron suspension particles. Calcium hydroxide is then converted into calcium oxide through high-temperature combustion and calcination, decomposing water vapor. At the same time, the iron powder reacts with oxygen and water vapor to convert into ferroferric oxide, thereby obtaining uniform calcium oxide / ferroferric oxide magnetic calcium salt particles.

[0022] 2. The liquid of the present invention uses an alkaline solution of sodium carboxymethyl cellulose containing disodium hydrogen phosphate to enhance the water disintegration resistance of the bone filler. The powder and liquid are blended in a ratio of 2:1 (g / mL) and applied to prepare a block bone filler of a specific shape. During the curing process, the calcium oxide in the magnetic calcium salt reacts with water and disodium hydrogen phosphate to produce some calcium phosphate and calcium hydroxide, which coat the ferroferric oxide particles, ultimately resulting in a novel calcium sulfate / ferroferric oxide / calcium hydroxide / calcium phosphate bone filler. Substances such as calcium sulfate and calcium phosphate contained in the bone filler are gradually degraded and absorbed, and calcium hydroxide can also play an antibacterial role, giving the bone filler containing the magnetic calcium salt an antibacterial effect.

[0023] 3. The magnetic calcium salt prepared by this invention can impart a certain degree of magnetism to bone fillers. This allows them to be heated by hysteresis in an alternating magnetic field, killing or eliminating tumors and providing high-temperature sterilization. The calcium hydroxide produced also exhibits certain antibacterial properties and can reduce the heating rate of Fe₃O₄ in an alternating magnetic field. In vitro studies have shown that its temperature rises to 95.9°C, close to the 90°C in vitro polymerization temperature of typical PMMA bone cement and significantly lower than the 500°C of pure ferroferric oxide, thus reducing the risk of burns to other tissues. The resulting new bone filler has a strength comparable to that of cancellous bone and can be used for fixation of various non-load-bearing fractures and filling of bone defects. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is the XRD pattern of the magnetic calcium salt prepared in Example 1 of the present invention;

[0025] Figure 2 From left to right are the temperature increase results of the bone fillers tested in Example 1, Example 3, and Example 6 under a magnetic field;

[0026] Figure 3 From left to right are the results of the compression strength of the bone fillers tested in Example 1, Example 2, Example 4, and Example 5;

[0027] Figure 4 This is a picture of an immersion test of the bone filler of Example 1 of the present invention;

[0028] Figure 5 This is a graph showing the degradation test of the bone filler according to Example 6 of the present invention. DETAILED DESCRIPTION

[0029] The structure of the present invention will be further described below with reference to the accompanying drawings and through examples. It should be noted that the present examples are descriptive rather than restrictive.

[0030] A bone filler containing magnetic calcium salt, the bone filler is a block of a specific shape, prepared by mixing and solidifying powder and liquid in a ratio of 2:1 (g / mL);

[0031] The powder comprises 18.3-38.5% by weight of magnetic calcium salt and 61.5-81.7% by weight of calcium sulfate. The liquid used is a sodium carboxymethyl cellulose solution containing disodium hydrogen phosphate, wherein the mass percentage of the disodium hydrogen phosphate is 0.16-2.52% and the mass percentage of the sodium carboxymethyl cellulose is 1.15-4.25%. In the magnetic calcium salt, the mass percentage of calcium oxide is 22-47%, and the mass percentage of ferrosoferric oxide is 53-78%. The particle size distribution range of the magnetic calcium salt is 2.7-83 μm. In the calcium sulfate, the mass percentage of calcium sulfate hemihydrate is 70-95%, and the rest is calcium sulfate dihydrate.

[0032] The preparation method of the bone filler containing magnetic calcium salt of the present invention is as follows:

[0033] Step 1, preparing a sodium carboxymethyl cellulose solution with a mass percentage of 3.28-6.52%, and then adding iron powder to the sodium carboxymethyl cellulose solution to prepare an iron powder suspension, wherein the mass percentage of iron powder to sodium carboxymethyl cellulose solution is (0.35-1.11):1;

[0034] Step 2, preparing a sodium hydroxide solution with a mass percentage of 10.7-47.3%, and a calcium chloride solution with a mass percentage of 14.2-42.5%;

[0035] Step 3, adding the iron powder suspension prepared in step 1 to the sodium hydroxide solution prepared in step 2, with the volume ratio of the two being 1:3; then adding the calcium chloride solution prepared in step 2 to the iron powder / sodium carboxymethyl cellulose / sodium hydroxide solution at a rate of 1.5-24 mL / min, with the volume ratio of the calcium chloride solution to the sodium hydroxide solution being 1:2;

[0036] Step 4: Continue stirring and reacting for 20-60 minutes to obtain an iron / calcium hydroxide suspension, and filter and wash to obtain an iron / calcium hydroxide precipitate;

[0037] Step 5: calcining the precipitate at 530-590° C. for 15-120 min, transferring it to a dryer and cooling it to room temperature; crushing and grinding it to obtain a magnetic calcium salt with controllable particle size and morphology;

[0038] Step 6: uniformly mixing a predetermined amount of magnetic calcium salt and a predetermined amount of calcium sulfate to obtain a powder;

[0039] Step 7, preparing a sodium carboxymethyl cellulose solution containing disodium hydrogen phosphate, wherein the mass percentage of disodium hydrogen phosphate is 0.16-2.52%, and the mass percentage of sodium carboxymethyl cellulose is 1.15-4.25%;

[0040] Step 8: Add the mixed powder to the liquid at a ratio of 2:1 g / mL. Stir for 10-60 seconds. Apply to the mold with the pre-cut holes. Curing for 10-20 minutes, then remove from the mold to obtain the bone filler. The bone filler can be shaped like a cube, cuboid, or cylinder.

[0041] Example 1

[0042] A magnetic calcium salt-containing bone filler, in the form of a φ6×12 mm cylinder, is prepared by mixing and solidifying powder and liquid in a ratio of 2:1 (g / mL);

[0043] The powder is composed of 38.5% by weight of magnetic calcium salt and 61.5% by weight of calcium sulfate. The liquid is a 2.52% sodium hydrogen phosphate solution of sodium carboxymethyl cellulose, with the sodium carboxymethyl cellulose content being 4.25% by weight. The magnetic calcium salt comprises 47% by weight of calcium oxide and 53% by weight of ferrosoferric oxide. The particle size distribution of the magnetic calcium salt is 2.7-83 μm. The calcium sulfate comprises 70% by weight of calcium sulfate hemihydrate and 30% by weight of calcium sulfate dihydrate.

[0044] The preparation method of the bone filler in this embodiment is as follows:

[0045] (1) preparing a sodium carboxymethyl cellulose solution with a mass percentage of 3.28%, and then adding iron powder to the sodium carboxymethyl cellulose solution to prepare an iron powder suspension, wherein the mass percentage of iron powder to sodium carboxymethyl cellulose solution is 0.35:1;

[0046] (2) Prepare a sodium hydroxide solution with a mass percentage of 47.3% and a calcium chloride solution with a mass percentage of 42.5%;

[0047] (3) Add 40 mL of the prepared iron powder suspension to 120 mL of the prepared sodium hydroxide solution; then add 60 mL of the prepared calcium chloride solution to the iron powder / sodium carboxymethyl cellulose / sodium hydroxide solution at a rate of 24 mL / min;

[0048] (4) continuing the reaction with stirring for 60 min to obtain an iron / calcium hydroxide suspension, which was filtered and washed to obtain an iron / calcium hydroxide precipitate;

[0049] (5) calcining the precipitate at 530°C for 120 minutes, transferring it to a desiccator and cooling it to room temperature; crushing and grinding it to obtain a magnetic calcium salt with controllable particle size and morphology;

[0050] (6) uniformly mixing a certain amount of magnetic calcium salt and a certain amount of calcium sulfate to obtain a powder;

[0051] (7) preparing a sodium carboxymethyl cellulose solution containing disodium hydrogen phosphate, wherein the mass percentage of disodium hydrogen phosphate is 2.52% and the mass percentage of sodium carboxymethyl cellulose is 4.25%;

[0052] (8) The uniformly mixed powder was added to the liquid in a powder to liquid ratio of 2:1 (g / mL), stirred for 60 seconds, and applied to the mold with the reserved hole. After curing for 10 minutes, the mold was demolded to obtain a bone filler containing magnetic calcium salt.

[0053] The magnetic calcium salt prepared in Example 1 was subjected to XRD pattern scanning. Figure 1As shown, the diffraction peaks are mainly those of ferroferric oxide and calcium oxide, indicating that the main component of the magnetic calcium salt is a complex of ferroferric oxide and calcium oxide;

[0054] The bone filler of Example 1 was subjected to magnetocaloric test on bone cement under an alternating magnetic field of 50KHZ. Figure 2 As shown in the figure, the magnetic thermal temperature of the bone filler containing magnetic calcium salt can reach 95.9℃ in 1 minute, which meets the requirement that the magnetic thermal treatment temperature is greater than 40℃.

[0055] The bone filler of Example 1 was subjected to a compressive strength test. Figure 3 As shown, the compressive strength of the bone filler containing magnetic calcium salt is 11.72 MPa, which meets the requirement of cancellous bone strength range of 2-10 MPa.

[0056] The bone filler of Example 1 was placed in a phosphate buffer solution. Figure 4 As shown in the figure, after standing for 24 hours, the solution was clear and no bone filler was found to fall off or peel off, indicating that the bone filler containing magnetic calcium salt has good resistance to water disintegration.

[0057] Example 2

[0058] A magnetic calcium salt-containing bone filler, in the form of a φ6×12 mm cylinder, is prepared by mixing and solidifying powder and liquid in a ratio of 2:1 (g / mL);

[0059] The powder comprises 20% by weight of magnetic calcium salt and 80% by weight of calcium sulfate; the liquid comprises a 0.16% sodium hydrogen phosphate solution of sodium carboxymethyl cellulose, with the sodium carboxymethyl cellulose content being 2.10% by weight; calcium oxide and ferrosoferric oxide in the magnetic calcium salt account for 35% and 65% of the magnetic calcium salt, respectively; the particle size distribution of the magnetic calcium salt is 5-53 μm; and calcium sulfate hemihydrate and dihydrate account for 90% and 10% of the calcium sulfate, respectively.

[0060] The preparation method of the bone filler in this embodiment is as follows:

[0061] (1) preparing a sodium carboxymethyl cellulose solution with a mass percentage of 6.52%, and then adding iron powder to the sodium carboxymethyl cellulose solution to prepare an iron powder suspension, wherein the mass percentage of iron powder to sodium carboxymethyl cellulose solution is 0.73:1;

[0062] (2) Prepare a sodium hydroxide solution with a mass percentage of 42.5% and a calcium chloride solution with a mass percentage of 41.5%;

[0063] (3) Add 40 mL of the prepared iron powder suspension to 120 mL of the prepared sodium hydroxide solution; then add 60 mL of the prepared calcium chloride solution to the iron powder / sodium carboxymethyl cellulose / sodium hydroxide solution at a rate of 6 mL / min;

[0064] (4) stirring the reaction for 45 min to obtain an iron / calcium hydroxide suspension, which was filtered and washed to obtain an iron / calcium hydroxide precipitate;

[0065] (5) calcining the precipitate at 590°C for 30 minutes, transferring it to a desiccator and cooling it to room temperature; crushing and grinding it to obtain a magnetic calcium salt with controllable particle size and morphology;

[0066] (6) uniformly mixing a certain amount of magnetic calcium salt and a certain amount of calcium sulfate to obtain a powder;

[0067] (7) preparing a sodium carboxymethyl cellulose solution containing disodium hydrogen phosphate, wherein the mass percentage of disodium hydrogen phosphate is 0.16% and the mass percentage of sodium carboxymethyl cellulose is 2.10%;

[0068] (8) The uniformly mixed powder was added to the liquid in a powder to liquid ratio of 1:1 (g / mL), stirred for 60 seconds, and applied to the mold with the reserved hole. After curing for 15 minutes, the mold was demolded to obtain a bone filler containing magnetic calcium salt.

[0069] The bone filler of Example 2 was subjected to a compressive strength test. The compressive strength of the bone filler containing magnetic calcium salt was 11.26 MPa, which met the requirement of cancellous bone strength range of 2-10 MPa.

[0070] Example 3

[0071] A magnetic calcium salt-containing bone filler, in the form of a φ6×12 mm cylinder, is prepared by mixing and solidifying powder and liquid in a ratio of 2:1 (g / mL);

[0072] The powder is 18.3% by weight of magnetic calcium salt and 81.7% by weight of calcium sulfate. The liquid is a 1.50% sodium hydrogen phosphate solution of sodium carboxymethyl cellulose, with the sodium carboxymethyl cellulose content being 1.15% by weight. Calcium oxide accounts for 22% by weight of the magnetic calcium salt, and ferrosoferric oxide accounts for 78% by weight of the magnetic calcium salt. The particle size distribution of the magnetic calcium salt is 5-45 μm. Calcium sulfate hemihydrate accounts for 95% by weight of the calcium sulfate, and calcium sulfate dihydrate accounts for 5% by weight of the calcium sulfate.

[0073] The preparation method of the bone filler in this embodiment is as follows:

[0074] (1) preparing a sodium carboxymethyl cellulose solution with a mass percentage of 4.50%, and then adding iron powder to the sodium carboxymethyl cellulose solution to prepare an iron powder suspension, wherein the mass percentage of iron powder to sodium carboxymethyl cellulose solution is 0.38:1;

[0075] (2) preparing a sodium hydroxide solution with a mass percentage of 10.7% and a calcium chloride solution with a mass percentage of 14.2%;

[0076] (3) Add 40 mL of the prepared iron powder suspension to 120 mL of the prepared sodium hydroxide solution; then add 60 mL of the prepared calcium chloride solution to the iron powder / sodium carboxymethyl cellulose / sodium hydroxide solution at a rate of 4.5 mL / min;

[0077] (4) stirring the reaction for 20 min to obtain an iron / calcium hydroxide suspension, which was filtered and washed to obtain an iron / calcium hydroxide precipitate;

[0078] (5) calcining the precipitate at 550°C for 15 minutes, transferring it to a desiccator and cooling it to room temperature; crushing and grinding it to obtain a magnetic calcium salt with controllable particle size and morphology;

[0079] (6) uniformly mixing a certain amount of magnetic calcium salt and a certain amount of calcium sulfate to obtain a powder;

[0080] (7) preparing a sodium carboxymethyl cellulose solution containing disodium hydrogen phosphate, wherein the mass percentage of disodium hydrogen phosphate is 1.50% and the mass percentage of sodium carboxymethyl cellulose is 1.15%;

[0081] (8) The uniformly mixed powder was added to the liquid in a powder to liquid ratio of 2:1 (g / mL), stirred for 30 seconds, and solidified for 20 minutes before demolding to obtain a bone filler containing magnetic calcium salt.

[0082] The bone filler of Example 3 was subjected to magnetothermal testing on bone cement in an alternating magnetic field of 50 KHZ. The magnetothermal temperature of the bone filler could reach 84.5° C. in 1 minute, meeting the requirement that the magnetothermal treatment temperature should be greater than 40° C.

[0083] Example 4

[0084] A magnetic calcium salt-containing bone filler, in the form of a φ6×12 mm cylinder, is prepared by mixing and solidifying powder and liquid in a ratio of 2:1 (g / mL);

[0085] The powder comprises 30% by weight of magnetic calcium salt and 70% by weight of calcium sulfate. The liquid comprises a 0.65% sodium hydrogen phosphate solution of sodium carboxymethyl cellulose, with the sodium carboxymethyl cellulose content being 3.10% by weight. The magnetic calcium salt comprises 44% by weight of calcium oxide and 56% by weight of ferrosoferric oxide. The particle size distribution of the magnetic calcium salt is 10-83 μm. The calcium sulfate comprises 80% by weight of calcium sulfate hemihydrate and 20% by weight of calcium sulfate dihydrate.

[0086] The preparation method of the bone filler in this embodiment is as follows:

[0087] (1) preparing a sodium carboxymethyl cellulose solution with a mass percentage of 4.0%, and then adding iron powder to the sodium carboxymethyl cellulose solution to prepare an iron powder suspension, wherein the mass percentage of iron powder to sodium carboxymethyl cellulose solution is 0.42:1;

[0088] (2) preparing a sodium hydroxide solution with a mass percentage of 35.0% and a calcium chloride solution with a mass percentage of 42.5%;

[0089] (3) Add 40 mL of the prepared iron powder suspension to 120 mL of the prepared sodium hydroxide solution; then add 60 mL of the prepared calcium chloride solution to the iron powder / sodium carboxymethyl cellulose / sodium hydroxide solution at a rate of 21 mL / min;

[0090] (4) continuing the reaction with stirring for 60 min to obtain an iron / calcium hydroxide suspension, which was filtered and washed to obtain an iron / calcium hydroxide precipitate;

[0091] (5) calcining the precipitate at 570°C for 60 minutes, transferring it to a desiccator and cooling it to room temperature; crushing and grinding it to obtain a magnetic calcium salt with controllable particle size and morphology;

[0092] (6) uniformly mixing a certain amount of magnetic calcium salt and a certain amount of calcium sulfate to obtain a powder;

[0093] (7) preparing a sodium carboxymethyl cellulose solution containing disodium hydrogen phosphate, wherein the mass percentage of disodium hydrogen phosphate is 0.65% and the mass percentage of sodium carboxymethyl cellulose is 3.10%;

[0094] (8) The uniformly mixed powder was added to the liquid in a powder to liquid ratio of 2:1 (g / mL), stirred for 10 seconds, and solidified for 11 minutes before demolding to obtain a bone filler containing magnetic calcium salt.

[0095] The bone filler of Example 4 was subjected to a compressive strength test. The compressive strength of the bone filler containing magnetic calcium salt was 13.52 MPa, which met the requirement of cancellous bone strength range of 2-10 MPa.

[0096] Example 5

[0097] A magnetic calcium salt-containing bone filler, in the form of a φ6×12 mm cylinder, is prepared by mixing and solidifying powder and liquid in a ratio of 2:1 (g / mL);

[0098] The powder is composed of 26% by weight of magnetic calcium salt and 74% by weight of calcium sulfate. The liquid is a sodium carboxymethyl cellulose solution containing 1.50% disodium hydrogen phosphate, with the sodium carboxymethyl cellulose content being 3.85% by weight. The magnetic calcium salt comprises 31% by weight of calcium oxide and 69% by weight of ferrosoferric oxide. The particle size distribution of the magnetic calcium salt is between 2.7 and 45 μm. The calcium sulfate comprises 92% by weight of calcium sulfate hemihydrate and 8% by weight of calcium sulfate dihydrate.

[0099] The preparation method of the bone filler in this embodiment is as follows:

[0100] (1) preparing a sodium carboxymethyl cellulose solution with a mass percentage of 3.52%, and then adding iron powder to the sodium carboxymethyl cellulose solution to prepare an iron powder suspension, wherein the mass percentage of iron powder to sodium carboxymethyl cellulose solution is 0.6:1;

[0101] (2) preparing a sodium hydroxide solution with a mass percentage of 25.8% and a calcium chloride solution with a mass percentage of 31%;

[0102] (3) Add 40 mL of the prepared iron powder suspension to 120 mL of the prepared sodium hydroxide solution; then add 60 mL of the prepared calcium chloride solution to the iron powder / sodium carboxymethyl cellulose / sodium hydroxide solution at a rate of 1.5 mL / min;

[0103] (4) continuing the reaction with stirring for 30 min to obtain an iron / calcium hydroxide suspension, which was filtered and washed to obtain an iron / calcium hydroxide precipitate;

[0104] (5) calcining the precipitate at 560°C for 45 minutes, transferring it to a desiccator and cooling it to room temperature; crushing and grinding it to obtain a magnetic calcium salt with controllable particle size and morphology;

[0105] (6) uniformly mixing a certain amount of magnetic calcium salt and a certain amount of calcium sulfate to obtain a powder;

[0106] (7) preparing a sodium carboxymethyl cellulose solution containing disodium hydrogen phosphate, wherein the mass percentage of disodium hydrogen phosphate is 1.50% and the mass percentage of sodium carboxymethyl cellulose is 3.85%;

[0107] (8) The uniformly mixed powder was added to the liquid mixture at a powder to liquid ratio of 2:1 (g / mL), stirred for 60 seconds, and solidified for 16 minutes before demolding to obtain a bone filler containing magnetic calcium salt.

[0108] The bone filler of Example 5 was subjected to a compressive strength test. The compressive strength of the bone filler containing magnetic calcium salt was 14.38 MPa, which met the requirement of cancellous bone strength range of 2-10 MPa.

[0109] Example 6

[0110] A magnetic calcium salt-containing bone filler, in the form of a φ6×12 mm cylinder, is prepared by mixing and solidifying powder and liquid in a ratio of 2:1 (g / mL);

[0111] The powder is composed of 35% by weight of magnetic calcium salt and 65% by weight of calcium sulfate. The liquid is a sodium carboxymethyl cellulose solution containing 0.56% disodium hydrogen phosphate, with the sodium carboxymethyl cellulose content being 2.6% by weight. The magnetic calcium salt comprises 28% by weight of calcium oxide and 72% by weight of ferrosoferric oxide. The particle size distribution of the magnetic calcium salt is 5-45 μm. The calcium sulfate comprises 89% by weight of calcium sulfate hemihydrate and 11% by weight of calcium sulfate dihydrate.

[0112] The preparation method of the bone filler in this embodiment is as follows:

[0113] (1) preparing a sodium carboxymethyl cellulose solution with a mass percentage of 6.18%, and then adding iron powder to the sodium carboxymethyl cellulose solution to prepare an iron powder suspension, wherein the mass percentage of iron powder to sodium carboxymethyl cellulose solution is 1.11:1;

[0114] (2) preparing a sodium hydroxide solution with a mass percentage of 22.5% and a calcium chloride solution with a mass percentage of 37.5%;

[0115] (3) Add 40 mL of the prepared iron powder suspension to 120 mL of the prepared sodium hydroxide solution; then add 60 mL of the prepared calcium chloride solution to the iron powder / sodium carboxymethyl cellulose / sodium hydroxide solution at a rate of 9 mL / min;

[0116] (4) continuing the reaction with stirring for 30 min to obtain an iron / calcium hydroxide suspension, which was filtered and washed to obtain an iron / calcium hydroxide precipitate;

[0117] (5) calcining the precipitate at 570°C for 30 minutes, transferring it to a desiccator and cooling it to room temperature; crushing and grinding it to obtain a magnetic calcium salt with controllable particle size and morphology;

[0118] (6) uniformly mixing a certain amount of magnetic calcium salt and a certain amount of calcium sulfate to obtain a powder;

[0119] (7) preparing a sodium carboxymethyl cellulose solution containing disodium hydrogen phosphate, wherein the mass percentage of disodium hydrogen phosphate is 0.56% and the mass percentage of sodium carboxymethyl cellulose is 2.6%;

[0120] (8) The uniformly mixed powder was added to the liquid in a powder to liquid ratio of 2:1 (g / mL), stirred for 60 seconds, and solidified for 13 minutes before demolding to obtain a bone filler containing magnetic calcium salt.

[0121] The bone filler of Example 6 was subjected to magnetothermal testing on bone cement under an alternating magnetic field of 50KHZ. The magnetothermal temperature of the bone filler containing magnetic calcium salt reached 104.1°C in 1 minute, meeting the requirement that the magnetothermal treatment temperature be greater than 40°C.

[0122] The magnetic calcium salt-containing bone filler of Example 6 was added to 2 mL of extraction medium (MEM medium containing serum) at a ratio of 0.4 g and incubated at 37±1°C for 24±2 hours to prepare an extract. The extract was then tested for relative cell viability according to the extract test method specified in GB / T 16886.5. The relative cell viability of the extract of Example 6 was 81.6%, which was greater than 70%, indicating no potential cytotoxicity.

[0123] The bone filler of Example 6 was immersed in 50 ml of phosphate buffer solution at 37°C. The solution was changed every 24 hours. Every 3 days, the bone filler was taken out, dried, weighed, and then placed in phosphate buffer solution for degradation study. Figure 5 As shown in the degradation curve, the bone filler degraded by 35.7% in 30 days.

[0124] Although the embodiments and drawings of the present invention are disclosed for illustrative purposes, those skilled in the art will understand that various replacements, changes and modifications are possible without departing from the spirit of the present invention and the appended claims. Therefore, the scope of the present invention is not limited to the contents disclosed in the embodiments and drawings.

Claims

1. A bone filler containing magnetic calcium salt, characterized in that: The bone filler is in block form and is prepared by mixing and solidifying a powder and a liquid in a ratio of 2:1 g / mL. The powder components and their weight percentages are: 61.5-81.7% calcium sulfate and 18.3-38.5% magnetic calcium salt. The liquid is a sodium carboxymethyl cellulose solution containing disodium hydrogen phosphate, with the weight percentage of disodium hydrogen phosphate being 0.16-2.52% and the weight percentage of sodium carboxymethyl cellulose being 1.15-4.25%. The magnetic calcium salt is a calcium oxide / ferroferric oxide complex, with the weight percentage of calcium oxide in the magnetic calcium salt being 22-47% and the weight percentage of ferroferric oxide in the magnetic calcium salt being 53-78%. The compounding method of the magnetic calcium salt comprises the following steps: Step 1, preparing a sodium carboxymethyl cellulose solution with a mass percentage of 3.28-6.52%, and then adding iron powder to the sodium carboxymethyl cellulose solution to prepare an iron powder suspension, wherein the mass percentage of iron powder to sodium carboxymethyl cellulose solution is (0.35-1.11):1; Step 2: preparing a sodium hydroxide solution having a mass percentage of 10.7-47.3% and a calcium chloride solution having a mass percentage of 14.2-42.5%; Step 3, adding the iron powder suspension prepared in step 1 to the sodium hydroxide solution prepared in step 2, with the volume ratio of the two being 1:3; then adding the calcium chloride solution prepared in step 2 to the iron powder / sodium carboxymethyl cellulose / sodium hydroxide solution at a rate of 1.5-24 mL / min, with the volume ratio of the calcium chloride solution to the sodium hydroxide solution being 1:2; Step 4: Continue stirring and reacting for 20-60 minutes to obtain an iron / calcium hydroxide suspension, and filter and wash to obtain an iron / calcium hydroxide precipitate; Step 5: calcine the precipitate at 530-590°C for 15-120 minutes, then transfer it to a desiccator and cool it to room temperature; Magnetic calcium salt with controllable particle size and morphology is obtained by crushing and grinding.

2. The bone filler containing magnetic calcium salt according to claim 1, characterized in that: The particle size distribution range of the magnetic calcium salt is 2.7-83 μm.

3. The bone filler containing magnetic calcium salt according to claim 1, characterized in that: Calcium sulfate is a mixture of calcium sulfate hemihydrate and calcium sulfate dihydrate, with calcium sulfate hemihydrate accounting for 70-95% of the mass percentage of calcium sulfate and the rest being calcium sulfate dihydrate.

4. A method for preparing a bone filler containing magnetic calcium salt according to any one of claims 1 to 3, characterized in that: The steps include: Step 1, preparing a sodium carboxymethyl cellulose solution with a mass percentage of 3.28-6.52%, and then adding iron powder to the sodium carboxymethyl cellulose solution to prepare an iron powder suspension, wherein the mass percentage of iron powder to sodium carboxymethyl cellulose solution is (0.35-1.11):1; Step 2: preparing a sodium hydroxide solution having a mass percentage of 10.7-47.3% and a calcium chloride solution having a mass percentage of 14.2-42.5%; Step 3, adding the iron powder suspension prepared in step 1 to the sodium hydroxide solution prepared in step 2, with the volume ratio of the two being 1:3; then adding the calcium chloride solution prepared in step 2 to the iron powder / sodium carboxymethyl cellulose / sodium hydroxide solution at a rate of 1.5-24 mL / min, with the volume ratio of the calcium chloride solution to the sodium hydroxide solution being 1:2; Step 4: Continue stirring and reacting for 20-60 minutes to obtain an iron / calcium hydroxide suspension, and filter and wash to obtain an iron / calcium hydroxide precipitate; Step 5: calcining the precipitate at 530-590°C for 15-120 minutes, transferring it to a dryer and cooling it to room temperature; crushing and grinding it to obtain a magnetic calcium salt with controllable particle size and morphology; Step 6: uniformly mixing a predetermined amount of magnetic calcium salt and a predetermined amount of calcium sulfate to obtain a powder; Step 7, preparing a sodium carboxymethyl cellulose solution containing disodium hydrogen phosphate, wherein the mass percentage of disodium hydrogen phosphate is 0.16-2.52%, and the mass percentage of sodium carboxymethyl cellulose is 1.15-4.25%; Step 8: Add the evenly mixed powder to the liquid at a ratio of 2:1 g / mL, stir for 10-60 seconds, apply it to the mold with the reserved hole, and solidify for 10-20 minutes before demolding to obtain a bone filler containing magnetic calcium salt.

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