CN108714249B - Method for preparing calcium carbonate-chitosan three-dimensional bone screw material by urea solubilization method - Google Patents

Method for preparing calcium carbonate-chitosan three-dimensional bone screw material by urea solubilization method Download PDF

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CN108714249B
CN108714249B CN201810575802.3A CN201810575802A CN108714249B CN 108714249 B CN108714249 B CN 108714249B CN 201810575802 A CN201810575802 A CN 201810575802A CN 108714249 B CN108714249 B CN 108714249B
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chitosan
calcium carbonate
bone screw
solution
screw material
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CN108714249A (en
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王征科
方雯
杨玲
聂景怡
胡巧玲
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Zhejiang University ZJU
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    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
    • A61L27/00—Materials for grafts or prostheses or for coating grafts or prostheses
    • A61L27/40—Composite materials, i.e. containing one material dispersed in a matrix of the same or different material
    • A61L27/44—Composite materials, i.e. containing one material dispersed in a matrix of the same or different material having a macromolecular matrix
    • A61L27/446—Composite materials, i.e. containing one material dispersed in a matrix of the same or different material having a macromolecular matrix with other specific inorganic fillers other than those covered by A61L27/443 or A61L27/46
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
    • A61L27/00—Materials for grafts or prostheses or for coating grafts or prostheses
    • A61L27/50—Materials characterised by their function or physical properties, e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
    • A61L2430/00—Materials or treatment for tissue regeneration
    • A61L2430/02—Materials or treatment for tissue regeneration for reconstruction of bones; weight-bearing implants

Abstract

The invention discloses a method for preparing a calcium carbonate-chitosan three-dimensional bone screw material by a urea solubilization method, which comprises the following steps: adding anhydrous calcium chloride powder into a chitosan solution, and adding urea for solubilization to gradually dissipate the precipitate in the system from turbidity to a clear and transparent uniform solution. Injecting the obtained homogeneous solution into cylindrical mold composed of semipermeable membrane, and soaking in NaOH and Na2CO3And (3) in a mixed coagulation bath, demolding, washing and drying to obtain the calcium carbonate-chitosan three-dimensional bone screw material. The preparation process is simple and quick, the prepared chitosan-calcium carbonate composite material introduces inorganic particles into the three-dimensional ordered structure of the hydrogel, and the calcium carbonate has the characteristics of gradient distribution and inconsistent shape along the radial direction. The invention uses urea to solubilize calcium chloride powder, ensures the uniformity and stability of the mixed solution, ensures that the content of inorganic substances in the product can reach 95 percent, is close to natural products such as nacre and the like, and is expected to be applied to orthopedics clinic.

Description

Method for preparing calcium carbonate-chitosan three-dimensional bone screw material by urea solubilization method
Technical Field
The invention relates to a method for preparing a calcium carbonate-chitosan three-dimensional bone screw material by a urea solubilization method.
Background
The nacreous layer is an organic-inorganic composite biomaterial with a natural layered structure, in which the content of organic matrix is about 5% and the content of calcium carbonate is up to 95%. The nacreous layer has a highly ordered "brick-mud" microstructure and superior strength and toughness. The three-dimensional structure of the calcium carbonate gel is formed by growing a water-soluble protein layer on an insoluble polymer substrate (chitin), and the layer of protein can guide the generation of calcium carbonate crystals. In recent years, the organic-inorganic bionic composite material simulating the shell pearl layer structure is gradually paid attention by the material science community.
The chitosan-calcium carbonate system is a key focus of research on the nacreous layer-imitating organic-inorganic composite material. Chitin is one of the important organic components in shells, and chitosan is a derivative of chitin, and the two have similar structures. The chitosan has better solubility and is more widely applied to various industries and scientific research. Calcium carbonate is an inorganic mineral widely existing in nature, has the characteristic of easy characterization and regulation of a crystal structure, and is a model mineral commonly used in laboratory research of organic-inorganic composite materials.
The chitosan hydrogel with ordered structure and excellent performance can be prepared by an in-situ precipitation method, and calcium salt inorganic substances can be introduced by combining with inorganic substance in-situ mineralization, wherein calcium carbonate can promote the amplification and regeneration of bone tissues. Therefore, the chitosan-calcium carbonate composite material with high inorganic matter content, which is prepared from the shell-like pearl layer, has important scientific significance and good application prospect in orthopedics clinic.
Disclosure of Invention
The invention aims to provide a method for preparing a calcium carbonate-chitosan three-dimensional bone screw material by a urea solubilization method aiming at the defects of the prior art.
The invention relates to a method for preparing a calcium carbonate-chitosan three-dimensional bone screw material by a urea solubilization method, which comprises the following steps:
1) weighing chitosan with the mass viscosity-average molecular weight of 1-120 ten thousand and the deacetylation degree of 60-95% as a solute, taking an acetic acid aqueous solution with the volume fraction of 2-20% as a solvent, stirring until the chitosan is completely dissolved, and preparing a chitosan solution A with the mass viscosity-average molecular weight of 2-10 wt.%;
2) weighing a certain mass of anhydrous calcium chloride powder, and adding the anhydrous calcium chloride powder into the chitosan solution A to form a mixture stock solution B; adding a certain amount of urea for solubilization to gradually dissipate the precipitate in the system, wherein the solution is changed from turbid to clear and transparent until the light transmittance of the mixed solution measured by a WGT-S haze meter is more than 90 percent to obtain a homogeneous mixed solution C;
3) injecting solution C into cylindrical mold composed of semipermeable membrane, and soaking in NaOH and Na2CO3Mixed coagulation bath, wherein the NaOH concentration is 2-10 wt.%, c (NaOH): c (Na)2CO3) Is 1:1-3:1；
4) And demolding the obtained chitosan-based composite gel, repeatedly washing the chitosan-based composite gel with deionized water to be neutral, and drying to obtain the calcium carbonate-chitosan three-dimensional bone screw material.
In the technical scheme, the added amount of the calcium chloride in the step 2) is calcium carbonate (CaCO) corresponding to calcium ions and the mass of the Chitosan (CS)3) The mass ratio of m (CS) to m (CaCO)3) Is 50:50-4: 96.
The preparation process is simple and quick, and the prepared chitosan-calcium carbonate composite material introduces a large amount of inorganic particles under the condition of keeping the original three-dimensional ordered structure of the hydrogel, which is difficult to realize by other organic-inorganic composite methods. The calcium carbonate exists in three forms of calcite granules, calcium carbonate balls and ball groups from inside to outside along the radial direction of the bone nail, and the calcium carbonate has the characteristic of gradient distribution along the radial direction. The invention uses urea to solubilize calcium chloride powder, ensures the uniformity and stability of the mixed solution, ensures that the content of inorganic substances in the product can reach 95 percent, is close to natural products such as nacre and the like, and is expected to be applied to orthopedics clinic.
Drawings
FIG. 1 is a scanning electron microscope image of a calcium carbonate-chitosan three-dimensional bone screw prepared by the present invention, wherein (a), (b), (c) are sequentially scanning photographs of a bone screw which is sliced from inside to outside along the radial direction, and (d), (e) and (f) are respectively the forms of calcium carbonate at the corresponding positions.
Detailed Description
The invention is further illustrated below with reference to specific examples.
Example 1:
1) weighing 1g of chitosan (with the viscosity-average molecular weight of 1 ten thousand and the deacetylation degree of 60%) and adding the chitosan into a 100mL beaker, adding 9mL of 2% acetic acid aqueous solution by volume fraction, and uniformly stirring to obtain 10 wt.% of chitosan solution A;
2) weighing a certain mass of anhydrous calcium chloride powder, and adding the anhydrous calcium chloride powder into the chitosan solution A to form a mixture stock solution B. The added amount of calcium carbonate (CaCO) corresponding to the calcium ion based on the mass of Chitosan (CS)3) Measured in mass ratio to theoretical value, m (CS) m (CaCO)3) Is 4: 96. Adding a certain amount of urea for solubilization until the light transmittance of the mixed solution measured by a WGT-S haze meter is more than 90%, and obtaining a homogeneous mixed solution C;
3) injecting solution C into cylindrical mold composed of semipermeable membrane, and soaking in NaOH and Na2CO3Mixed coagulation bath, wherein NaOH concentration is 2 wt.%, c (NaOH): c (Na)2CO3) 1: 1;
4) and demolding the obtained chitosan-based composite gel, repeatedly washing the chitosan-based composite gel with deionized water to be neutral, and drying to obtain the chitosan-calcium carbonate three-dimensional bone screw material.
The inorganic matter content of the chitosan-calcium carbonate three-dimensional bone screw material prepared by the embodiment is 95.6 percent.
Example 2:
1) weighing 1g of chitosan (with the viscosity-average molecular weight of 20 ten thousand and the deacetylation degree of 70%) and adding the chitosan into a 100mL beaker, adding 11.5mL of acetic acid aqueous solution with the volume fraction of 5%, and uniformly stirring to obtain 8 wt.% of chitosan solution A;
2) weighing a certain mass of anhydrous calcium chloride powder, and adding the anhydrous calcium chloride powder into the chitosan solution A to form a mixture stock solution B. The added amount of calcium carbonate (CaCO) corresponding to the calcium ion based on the mass of Chitosan (CS)3) Measured in mass ratio to theoretical value, m (CS) m (CaCO)3) Is 15: 85. Adding a certain amount of urea for solubilization until the light transmittance of the mixed solution measured by a WGT-S haze meter is more than 90%, and obtaining a homogeneous mixed solution C;
3) injecting solution C into cylindrical mold composed of semipermeable membrane, and soaking in NaOH and Na2CO3Mixed coagulation bath, where NaOH concentration is 4 wt.%, c (NaOH): c (Na)2CO3) 1: 1;
4) and demolding the obtained chitosan-based composite gel, repeatedly washing the chitosan-based composite gel with deionized water to be neutral, and drying to obtain the chitosan-calcium carbonate three-dimensional bone screw material.
The content of inorganic matters in the chitosan-calcium carbonate three-dimensional bone screw material prepared by the embodiment is 83.1 percent.
Example 3:
1) weighing 1g of chitosan (with the viscosity-average molecular weight of 50 ten thousand and the deacetylation degree of 80%) and adding the chitosan into a 100mL beaker, then adding 19mL of acetic acid aqueous solution with the volume fraction of 10%, and uniformly stirring to obtain 5 wt.% of chitosan solution A;
2) weighing a certain mass of anhydrous calcium chloride powder, and adding the anhydrous calcium chloride powder into the chitosan solution A to form a mixture stock solution B. The added amount of calcium carbonate (CaCO) corresponding to the calcium ion based on the mass of Chitosan (CS)3) Measured in mass ratio to theoretical value, m (CS) m (CaCO)3) Is 25: 75. Adding a certain amount of urea for solubilization until the light transmittance of the mixed solution measured by a WGT-S haze meter is more than 90%, and obtaining a homogeneous mixed solution C;
3) injecting solution C into cylindrical mold composed of semipermeable membrane, and soaking in NaOH and Na2CO3Mixed coagulation bath, wherein NaOH concentration is 5 wt.%, c (NaOH): c (Na)2CO3) Is 2: 1;
4) and demolding the obtained chitosan-based composite gel, repeatedly washing the chitosan-based composite gel with deionized water to be neutral, and drying to obtain the chitosan-calcium carbonate three-dimensional bone screw material.
The inorganic matter content of the chitosan-calcium carbonate three-dimensional bone screw material prepared by the embodiment is 74.4 percent.
Example 4:
1) weighing 1g of chitosan (with the viscosity-average molecular weight of 100 ten thousand and the deacetylation degree of 90%) and adding the chitosan into a 100mL beaker, adding 24mL of acetic acid aqueous solution with the volume fraction of 15%, and uniformly stirring to obtain 4 wt.% of chitosan solution A;
2) weighing a certain mass of anhydrous calcium chloride powder, and adding the anhydrous calcium chloride powder into the chitosan solution A to form a mixture stock solution B. The added amount of calcium carbonate (CaCO) corresponding to the calcium ion based on the mass of Chitosan (CS)3) Measured in mass ratio to theoretical value, m (CS) m (CaCO)3) Is 35: 65. Adding a certain amount of urea for solubilization until the light transmittance of the mixed solution measured by a WGT-S haze meter is more than 90%, and obtaining a homogeneous mixed solution C;
3) injecting solution C into cylindrical mold composed of semipermeable membrane, and soaking in NaOH and Na2CO3In a mixed coagulation bath, in which the NaOH concentration is 8 wt.%, c(NaOH)：c(Na2CO3) Is 2: 1;
4) and demolding the obtained chitosan-based composite gel, repeatedly washing the chitosan-based composite gel with deionized water to be neutral, and drying to obtain the chitosan-calcium carbonate three-dimensional bone screw material.
The inorganic matter content of the chitosan-calcium carbonate three-dimensional bone screw material prepared by the embodiment is 63.2 percent.
Example 5:
1) weighing 1g of chitosan (with the viscosity-average molecular weight of 120 ten thousand and the deacetylation degree of 95%) and adding the chitosan into a 100mL beaker, adding 49mL of 20% volume fraction acetic acid aqueous solution, and uniformly stirring to obtain 2 wt.% chitosan solution A;
2) weighing a certain mass of anhydrous calcium chloride powder, and adding the anhydrous calcium chloride powder into the chitosan solution A to form a mixture stock solution B. The added amount of calcium carbonate (CaCO) corresponding to the calcium ion based on the mass of Chitosan (CS)3) Measured in mass ratio to theoretical value, m (CS) m (CaCO)3) Is 50: 50. Adding a certain amount of urea for solubilization until the light transmittance of the mixed solution measured by a WGT-S haze meter is more than 90%, and obtaining a homogeneous mixed solution C;
3) injecting solution C into cylindrical mold composed of semipermeable membrane, and soaking in NaOH and Na2CO3Mixed coagulation bath, where NaOH concentration is 10 wt.%, c (NaOH): c (Na)2CO3) Is 3: 1;
4) and demolding the obtained chitosan-based composite gel, repeatedly washing the chitosan-based composite gel with deionized water to be neutral, and drying to obtain the chitosan-calcium carbonate three-dimensional bone screw material.
The inorganic matter content of the chitosan-calcium carbonate three-dimensional bone screw material prepared by the embodiment is 49.5 percent.
Example 6:
1) weighing 1g of chitosan (with the viscosity-average molecular weight of 20 ten thousand and the deacetylation degree of 70%) and adding the chitosan into a 100mL beaker, adding 11.5mL of acetic acid aqueous solution with the volume fraction of 5%, and uniformly stirring to obtain 8 wt.% of chitosan solution A;
2) weighing a certain mass of anhydrous calcium chloride powder, and adding the anhydrous calcium chloride powder into the chitosan solution A to form a mixture stock solution B. The added amount is Chitosan (CS)Calcium carbonate (CaCO) with mass corresponding to calcium ion3) Measured in mass ratio to theoretical value, m (CS) m (CaCO)3) Is 15: 85. The mixed solution B has precipitate, and always presents a turbid gel state under the condition of solubilization without adding urea, and subsequent operations such as solidification, washing, drying and the like cannot be carried out. It can be seen that the chitosan-calcium carbonate three-dimensional bone screw material cannot be prepared without adding urea for solubilization.

Claims (3)

1. A method for preparing a calcium carbonate-chitosan three-dimensional bone screw material by a urea solubilization method is characterized in that calcium carbonate exists in the three-dimensional bone screw material in the forms of calcite granules, calcium carbonate spheres and sphere groups from inside to outside along the radial direction of a bone screw, and the calcium carbonate has the characteristic of gradient distribution along the radial direction, and the method comprises the following steps:
1) weighing chitosan with the mass viscosity-average molecular weight of 1-120 ten thousand and the deacetylation degree of 60-95% as a solute, taking an acetic acid aqueous solution with the volume fraction of 2-20% as a solvent, stirring until the chitosan is completely dissolved, and preparing a chitosan solution A with the mass viscosity-average molecular weight of 2-10 wt.%;
2) weighing a certain mass of anhydrous calcium chloride powder, and adding the anhydrous calcium chloride powder into the chitosan solution A to form a mixture stock solution B; adding a certain amount of urea for solubilization until the light transmittance of the mixed solution measured by a WGT-S haze meter is more than 90%, and obtaining a homogeneous mixed solution C;
3) injecting solution C into cylindrical mold composed of semipermeable membrane, and soaking in NaOH and Na2CO3Mixed coagulation bath, wherein the NaOH concentration is 2-10 wt.%, c (NaOH): c (Na)2CO3) 1:1-3: 1;
4) and demolding the obtained chitosan-based composite gel, repeatedly washing the chitosan-based composite gel with deionized water to be neutral, and drying to obtain the calcium carbonate-chitosan three-dimensional bone screw material.
2. The method for preparing calcium carbonate-chitosan three-dimensional bone screw material according to claim 1, wherein the calcium chloride is added in an amount corresponding to the calcium ions based on the mass of Chitosan (CS)Calcium carbonate (CaCO)3) Measured in mass ratio to theoretical value, m (CS) m (CaCO)3) Is 50:50-4: 96.
3. The method for preparing the calcium carbonate-chitosan three-dimensional bone screw material by the urea solubilization method according to claim 1, which is characterized in that: the calcium carbonate-chitosan three-dimensional bone screw material contains up to 50-95% of calcium carbonate by mass.
CN201810575802.3A 2018-06-06 2018-06-06 Method for preparing calcium carbonate-chitosan three-dimensional bone screw material by urea solubilization method Expired - Fee Related CN108714249B (en)

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CN110172859B (en) * 2019-06-26 2021-11-05 陕西科技大学 Papermaking filling method based on gel in-situ growth coated calcium carbonate filler
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CN112007619B (en) * 2020-08-28 2023-03-31 玉林师范学院 Chitosan calcium carbonate composite adsorbent for adsorption and preparation method thereof

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