CN105347322A - Spherical nano-porous hydroxylapatite prepared through shells and preparation method thereof - Google Patents

Abstract

The invention discloses a spherical nanoporous hydroxyapatite prepared from shells and a preparation method thereof. It belongs to the technical field of material preparation. The hydroxyapatite prepared by this method is spherical, with a diameter of 4-5 μm, good dispersion, a specific surface area of 270 cm ² /g, and an average pore diameter of 18 nm. Stone composition is similar, biocompatibility is good. The preparation method is as follows: wash and dry the shells and grind them, then add acetic acid with a concentration of 0.1g/mL to fully react, add the H ₃ PO ₄ solution dropwise to the prepared calcium acetate solution, and then add trisodium citrate After stirring and reacting, add urea, stir and react the obtained solution in a water bath at 80-90° C. for 5 minutes, then let it stand until precipitation appears, filter the obtained precipitate, wash, dry and collect. The method does not need calcined shell powder, has short reaction time, does not need to adjust pH, is simple to operate, has good repeatability, and easily obtains raw materials, realizes waste utilization, and is beneficial to energy saving and emission reduction.

Description

A spherical nanoporous hydroxyapatite prepared from shells and its preparation method

technical field

The invention belongs to the technical field of preparation methods of hydroxyapatite, and in particular relates to a spherical nanoporous hydroxyapatite prepared from shells and a preparation method thereof.

technical background

Hydroxyapatite is an important medical material, which is consistent with the composition and structure of hard tissues of the human body, such as bones and teeth. It has good biocompatibility and chemical stability. It has important applications in bone substitutes, hard tissue repair, and carrier materials. Studies have found that hydroxyapatite can also adsorb heavy metal ions and certain organic substances in water.

With the development of my country's marine aquaculture industry, a large number of discarded shells have been produced in coastal areas, and the accumulation of a large number of shells has not only caused environmental pollution, but also prevented effective use of resources. Using shells to prepare hydroxyapatite not only alleviates environmental problems, but also can make full use of waste resources and turn waste into treasure.

The main inorganic component of mussel shells is calcium carbonate (95%), with some organic matter (proteins and polysaccharides) and other metal ions. The spherical hydroxyapatite prepared from discarded shells is non-stoichiometric, because there are traces of other ions (such as Fe ²⁺ , Mg ²⁺ , Si ²⁺ , F ^- ) entering the crystal structure, making the final synthesized hydroxyapatite Ca/P<1.67 of limestone. Chinese patent (Application No. 201410074680.1) discloses a method for preparing hydroxyapatite. This method uses discarded marine shells as raw materials to prepare hydroxyapatite. The obtained particle size is 10nm-80nm, and the reaction needs to be carried out at 100-200°C. In the process of preparation, the pH needs to be adjusted, the particle size distribution is not uniform, and the method is relatively complicated. Amin Shavandi et al. prepared nano-hydroxyapatite (Materials Chemistry and Physics 149-150 (2015) 607-616) by microwave method using mussel shells as raw materials. The obtained particles were rod-shaped, with a width of 15-20 nm and a length of 30-70 nm, _The method mentioned in the article requires calcining mussel shells at 900 °C to convert CaCO3 into CaO, which wastes energy in the preparation process.

The invention uses discarded shell resources as raw materials, does not need to calcinate shells in the preparation process, does not need to adjust pH, has mild reaction conditions, simple method, short preparation time, realizes waste utilization, and is beneficial to energy saving and emission reduction. The prepared hydroxyphosphorus Limestone particles have good biocompatibility and can be used for bone substitutes, hard tissue repair, etc., as well as catalysts and adsorbents for heavy metal ions in water.

Contents of the invention

Aiming at the resource waste and utilization of shells, the object of the present invention is to provide a spherical nanoporous hydroxyapatite prepared from shells and a preparation method thereof.

The present invention uses shells as raw materials to prepare the spherical nanoporous hydroxyapatite material. The particle surface of the material has a honeycomb nanoporous structure, the particle size is 4-5 μm, the specific area is 270 ^cm2 /g, and the particle surface has a pore diameter Porous structure with an average of 18nm.

Preferably, the hydroxyapatite is carbonate-containing hydroxyapatite. The raw materials used for preparing the material are shells, and the shells are one or more of mussel shells, oyster shells, pearl shells, mother-of-pearl shells, and mussel shells.

The present invention also provides a method for preparing a spherical nanoporous hydroxyapatite material prepared from shells, comprising the following steps:

1) Clean the shells, dry them at 50-70°C, and grind them into powders with a particle size of 100-400 mesh;

2) Take 0.5-1.0g of shell powder, add 20-40mL of dilute acetic acid with a concentration of 0.1g/mL, react for 1-2h, take the supernatant after centrifugation, and dilute to 50-100mL with deionized water;

3) Add 50-100 mL of H ₃ PO ₄ solution to the solution in step 2) at a rate of 10-20 drops/min, and constant stirring is required during the dropping process; the concentration of the H ₃ PO ₄ solution is 0.06 ~0.12mol/L;

4) Add 0.4 to 1.0 mmol of trisodium citrate to the solution in step 3), and continue the reaction for 10 to 30 minutes after adding;

5) Add 4 to 8 g of urea to the solution in step 4), and stir while adding;

6) Stir the solution in step 5) in a water bath at 80-90°C for 5-10 minutes, and let stand until precipitation occurs;

7) Filter the obtained precipitate, wash with deionized water for 2 to 3 times, and then wash with ethanol for 2 to 3 times;

8) Dry the obtained particles at 70-100° C. for 24 hours.

The invention prepares spherical nano-porous hydroxyapatite by using shells as raw materials.

The present invention has the following advantages:

(1) The present invention uses shells as raw materials to prepare spherical nanoporous hydroxyapatite, which realizes the resource utilization of shells, the raw materials used are cheap and easy to obtain, and the preparation conditions are mild.

(2) The Ca/P of spherical hydroxyapatite prepared by the present invention is less than 1.67, and there is carbonate radical instead of phosphate radical, which is similar to the composition of hydroxyapatite in bone.

(3) The present invention does not need to calcinate shells, does not need to adjust pH, has low requirements on experimental instruments, and the method is simple and easy to operate. The obtained particles are spherical, uniform in particle size, good in dispersibility and large in specific surface area.

Description of drawings

Fig. 1 is the scanning electron microscope picture of embodiment product.

Fig. 2 is the XRD spectrum of the product of the example.

Fig. 3 is the FTIR spectrum of the product of the example.

Fig. 4 is the TG spectrum of embodiment product.

Fig. 5 is a nitrogen adsorption-desorption isotherm picture of the product of the example.

Fig. 6 is the cytotoxicity test of the products of the examples on osteoblast MTT.

detailed description

In order to make the present invention easy to understand, the present invention will be further set forth by the following examples. It should be understood that the following examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. The specific experimental methods not mentioned in the following examples , usually in accordance with conventional experimental methods.

Example 1

After cleaning and drying the mussel shells, grind them into a powder with a particle size of 100 mesh, take 0.5g of shell powder and add it to a beaker; add 20mL of acetic acid solution with a concentration of 0.1g/mL, react for 1h, take the supernatant after centrifugation, and use Dilute to 50mL with deionized water; take 50mL of 0.06mol/L H ₃ PO ₄ solution, add H ₃ PO ₄ solution dropwise to the solution at a rate of 10 drops/min while stirring; then add 0.4mmol lemon to the mixed solution Sodium trisodium acid, stirred for 30 minutes, then added 6 g of urea; put the prepared mixed solution in a water bath at 90 ° C, stirred for 5 minutes, and stood until precipitation appeared; finally filtered the obtained precipitate and washed it with deionized water for 2 times, washed with ethanol twice, and dried at 70°C for 24 hours to obtain spherical hydroxyapatite particles.

The characteristic of the spherical nanoporous hydroxyapatite is that the particle diameter is 4-5 μm, the specific area is 270 cm ² /g, and the particle surface has a porous structure with an average pore diameter of 18 nm.

The scanning electron microscope picture of the spherical nanoporous hydroxyapatite is shown in Fig. 1; the XRD pattern is shown in Fig. 2; the FTIR pattern is shown in Fig. 3; the TG pattern is shown in Fig. 4; The cytotoxicity test of MTT is shown in Figure 6.

Example 2

After cleaning and drying the mussel shells, grind them into a powder with a particle size of 100 mesh, take 0.5g of shell powder and add it to a beaker; add 20mL of acetic acid solution with a concentration of 0.1g/mL, react for 1h, take the supernatant after centrifugation, and use Dilute to 50mL with deionized water; take 50mL of 0.12mol/L H ₃ PO ₄ solution, add H ₃ PO ₄ solution dropwise to the solution at a rate of 10 drops/min while stirring; then add 0.4mmol lemon to the mixed solution Sodium trisodium acid, stirred for 30 minutes, then added 6 g of urea; put the prepared mixed solution in a water bath at 90 ° C, stirred for 5 minutes, and stood until precipitation appeared; finally filtered the obtained precipitate and washed it with deionized water for 2 times, washed with ethanol twice, and dried at 70°C for 24 hours to obtain spherical hydroxyapatite particles.

Example 3

After cleaning and drying the oyster shells, grind them into a powder with a particle size of 200 mesh, take 0.5g shell powder and add it to a beaker; add 20ml of acetic acid solution with a concentration of 0.1g/mL, react for 1h, and take the supernatant after centrifugation, and use Dilute to 50mL with deionized water; take 50mL of 0.06mol/L H ₃ PO ₄ solution, add H ₃ PO ₄ solution dropwise to the solution at a rate of 20 drops/min while stirring; then add 0.6mmol lemon to the mixed solution trisodium acid, stirred for 30 minutes, then added 6 g of urea; put the prepared mixed solution in a water bath at 80 ° C, stirred and reacted for 5 minutes, and stood until precipitation appeared; finally, filtered the obtained precipitate and washed it with deionized water for 2 times, washed with ethanol twice, and dried at 70°C for 24 hours to obtain spherical hydroxyapatite particles.

Example 4

After cleaning and drying the pearl shells, grind them into a powder with a particle size of 100 mesh, take 0.5g shell powder and add it to a beaker; add 20mL of acetic acid solution with a concentration of 0.1g/mL, react for 1h, take the supernatant after centrifugation, and use Dilute to 50mL with deionized water; take 50mL of 0.06mol/L H ₃ PO ₄ solution, add H ₃ PO ₄ solution dropwise to the solution at a rate of 20 drops/min while stirring; then add 0.6mmol lemon to the mixed solution trisodium acid, stirred for 30 minutes, then added 8 g of urea; put the prepared mixed solution in a water bath at 80 ° C, stirred for 5 minutes, and stood until precipitation appeared; finally, filtered the obtained precipitate and washed it with deionized water for 2 times, washed with ethanol twice, and dried at 70°C for 24 hours to obtain spherical hydroxyapatite particles.

Example 5

After cleaning and drying the mussel shells, grind them into a powder with a particle size of 400 mesh, take 1.0 g of shell powder and add it to a beaker; add 40 mL of acetic acid solution with a concentration of 0.1 g/mL, react for 2 hours, and take the supernatant after centrifugation. Dilute to 100mL with deionized water; take 100mL of 0.12mol/L H ₃ PO ₄ solution, add H ₃ PO ₄ solution dropwise to the solution at a rate of 20 drops/min while stirring; then add 1.0mmol Trisodium citrate, stirred and reacted for 30 minutes, then added 8g of urea; put the prepared mixture in a water bath at 80°C, stirred and reacted for 5 minutes, and stood until precipitation appeared; finally, filtered the obtained precipitate and washed it with deionized water Wash twice with ethanol, and dry at 70° C. for 24 hours to obtain spherical hydroxyapatite particles.

The spherical nanoporous hydroxyapatite obtained in Examples 2, 3, 4 and 5 all have the same characteristic parameters as the spherical nanoporous hydroxyapatite obtained in Example 1.

Claims (4)

1. A spherical nanoporous hydroxyapatite material prepared from shells, characterized in that: the surface of the material particles has a honeycomb nanoporous structure, the particle size is 4 to 5 μm, and the specific area is 270cm ² /g. The particle surface has a porous structure with an average pore diameter of 18 nm. 2. A spherical nanoporous hydroxyapatite material prepared from shells according to claim 1, characterized in that said hydroxyapatite is carbonate-containing hydroxyapatite. 3. A kind of spherical nanoporous hydroxyapatite material prepared by utilizing shells according to claim 1, characterized in that the used raw materials for preparing said materials are shells, and said shells are mussel shells, oyster shells, pearl shells , one or more of mother-of-pearl shells and mussel shells. 4. A kind of spherical nanoporous hydroxyapatite material prepared by utilizing shells according to any one of claims 1-3, characterized in that its preparation method comprises the steps: 1) Clean the shells, dry them at 50-70°C, and grind them into powders with a particle size of 100-400 mesh; 2) Take 0.5-1.0g of shell powder, add 20-40mL of dilute acetic acid with a concentration of 0.1g/mL, react for 1-2h, take the supernatant after centrifugation, and dilute to 50-100mL with deionized water; 3) Add 50-100 mL of H ₃ PO ₄ solution to the solution in step 2) at a rate of 10-20 drops/min, and constant stirring is required during the dropping process; the concentration of the H ₃ PO ₄ solution is 0.06 ~0.12mol/L; 4) Add 0.4 to 1.0 mmol of trisodium citrate to the solution in step 3), and continue the reaction for 10 to 30 minutes after adding; 5) Add 4 to 8 g of urea to the solution in step 4), and stir while adding; 6) Stir the solution in step 5) in a water bath at 80-90°C for 5-10 minutes, and let stand until precipitation occurs; 7) Filter the obtained precipitate, wash with deionized water for 2 to 3 times, and then wash with ethanol for 2 to 3 times; 8) Dry the obtained particles at 70-100° C. for 24 hours.