CN1103849A - Method for prepn. of ball shaped hydroxy-apatite with homogeneous precipitation - Google Patents
Method for prepn. of ball shaped hydroxy-apatite with homogeneous precipitation Download PDFInfo
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Abstract
This invention relates to a method for preparing spheroidal hydroxy phospherite by using homogeneous sedimentation. The process is: a precipitator (urea or hexamethyl tetramine) or complexing agent (complexon 2 or EDTA) and oxidant (hydrogen peroxide) are added to an aqueous solution containing clacium ions and phosphate ions of a certain concentration to conduct homogeneous reaction, and a spheroidal precipitate is produced under the condition of certain reaction. In the invention no prilling process is needed. And it has simple technology and equipment, easy operation and low cost, can directly produce spheroidal precipitate, may have spheroids of different grain sizes obtd.
Description
The present invention relates to a kind of method for preparing ball shaped hydroxy-apatite, especially adopt precipitation from homogeneous solution (PFHS) to prepare the method for ball shaped hydroxy-apatite.
Hydroxyapatite is a kind of inorganic salt, also exists at nature.Because it has good consistency to organism, is a kind of good artificial dentistry, orthopaedics material.
1956 by people such as Tiselius (Arch.Biochem.65(1956) 132) at first hydroxyapatite is used as proteinic chromatography separation media.In the normal state, hydroxyapatite is irregular tabular crystal, the skewness in chromatographic column, and broken easily in chromatographic process, influence its separation performance.In order to improve the chromatographic property of hydroxyapatite, the someone begins to develop ball shaped hydroxy-apatite.Also wait people (J.of the Ceramic Society of Japan, 1987,95(5), 759) to adopt the spray pyrolysis technology to make spherical particle about 5um as aboveground thousand; The sharp bright people (BUNSEKIKAGAKU that waits of assistant rattan, 1989,38,34) with the granulation of hydroxyapatite crystallite, sintering, the method for preparing ball shaped hydroxy-apatite is hydroxyapatite powder to be put into to contain by the polymkeric substance of organic solvent dissolution and the aqueous solution earlier, and high-speed stirring makes its emulsification, remove organic phase then, make polymer cure, obtain spheroidal particle, sintering obtains the hydroxyapatite spherical particle again.These methods all relate to a granulation process.Granulation process technology, the complicated cost height of equipment, molecule granulation operation is difficult to grasp broad particle distribution.
The purpose of this invention is to provide a kind of technology, equipment is simple; The single step reaction globulate, good sphericity; Easy handling can conveniently be controlled size, and the precipitation from homogeneous solution (PFHS) that cost is low prepares the method for ball shaped hydroxy-apatite.
Concrete solution of the present invention is: a kind of precipitation from homogeneous solution (PFHS) prepares the method for ball shaped hydroxy-apatite, it is characterized in that: in the aqueous solution that contains certain density calcium ion and phosphate anion, add precipitation agent or network and agent and oxygenant, under the certain reaction condition homogeneous reaction taking place, generates spherical precipitation.Its example 1: the mol ratio of reagent calcium ion and phosphate anion is: 1.2～4.5; Precipitation agent is: urea or hexamethylenetetramine, and the concentration of precipitation agent exists: 0.001～10mol/l; The concentration of precipitation from homogeneous solution (PFHS) reagent exists: 0.0001～3mol/l, and temperature of reaction is between room temperature to 400 ℃, and the reaction times is between 5 minutes to 20 hours.Its example 2: the mol ratio of reagent calcium ion and phosphate anion is: 1.2～4.5; Network and agent are: ethylenediamine tetraacetic acid (EDTA) or EDTA or citric acid and Citrate trianion, and the concentration of complexing agent should equate with calcium ion concn in the reaction system or is high slightly; Oxygenant is: hydrogen peroxide, and oxidant concentration is: 1～20%, the concentration of precipitation from homogeneous solution (PFHS) reagent is at 0.0001～3mol/l, and temperature of reaction is between room temperature to 400 ℃, and the reaction times is between 5 minutes to 20 hours.
Principle of the present invention is: utilize the precipitation from homogeneous solution (PFHS) reaction, directly generate spheroidal particle from soluble calcium salt and phosphate solution under the condition of the number of controlling the nucleus generation and rate of crystal growth.Precipitation from homogeneous solution (PFHS) is meant and at a time reaches supersaturated condition everywhere simultaneously in reaction system, thereby obtains uniform deposit seeds.A long time ago, AC is used this technology and is obtained the precipitation that macrobead is convenient to wash.Shang Weiyou utilizes this principle to prepare ball shaped hydroxy-apatite.
The invention provides the homogeneous reaction condition and adopted dual mode.The pH value control of first reaction system; It two is calcium ion concn control in the reaction system.
PH value of reaction system control:
The solubleness of calcium phosphate in alkaline aqueous solution is very low, and solubility product is 1 * 10
-115～1 * 10
-110, but along with the reduction of pH value, solubleness increases, when the pH value less than 5 the time, it dissolves fully.Therefore can from the acidic solution that contains finite concentration calcium ion and phosphate anion, pass through the pH precipitate phosphoric acid salt of regulator solution.In this system, can obtain precipitation of hydroxyapatite by alkali neutral way, but because each degree of the satiety in the system can not be evenly, thereby sedimentary granular size and shape are various.The present invention adds so-called precipitation agent in the acid-reaction system of calcium ions and phosphate anion, when reaction conditions changes, precipitation agent decomposes, thereby change the pH value of reaction system, make calcium phosphate precipitation, owing under this reaction conditions, reach supersaturation in the system everywhere simultaneously and promptly reach precipitation from homogeneous solution (PFHS), thereby can obtain the spheroidal particle precipitation.
Precipitation agent of the present invention is meant the compound that deposition condition is provided for calcium phosphate salt such as hydroxyapatites under reaction conditions.
The control of cation concn:
In general, desire to make calcium phosphate salt precipitations such as hydroxyapatite in reaction system, the concentration of calcium positively charged ion and phosphate anion must reach supersaturation.For the homogeneous reaction condition is provided, the present invention at first will be by stoichiometric calcium ion and complexing agent reacting generating complex, calcium ion is sheltered, add phosphate anion and oxygenant, when reaction system changes, for example add the heat collapse complex compound, discharging of calcium ion, with the phosphate anion reaction, when the calcium ion concn that discharges reaches supersaturation, just obtain calcium phosphate precipitation.Because in the reaction system, the release of calcium ion is uniformly, thereby forms the homogeneous reaction condition, obtains the spheric calcium phosphate precipitation.
Among the present invention, employed precipitation agent is urea or hexamethylenetetramine or methane amide.
Following reaction, can take place in the aqueous solution of heating urea:
The ammonia that discharges can change the pH value in the reaction system.
Following reaction, can take place in the heating hexamethylenetetramine aqueous solution:
The ammonia that discharges can change the pH value in the reaction system.
Consumption 0.001～the 10mol/l of precipitation agent is for well, and the pH value that is lower than the 0.001mol/l reaction system changes little, surpasses 10mol/l, and the precipitation agent consumption is excessive, and is uneconomical.
Employed complexing agent is the EDTA(disodium EDTA among the present invention) or ethylenediamine tetraacetic acid (EDTA) or citric acid, lemon salt, trolamine etc.With EDTA is example, is described as follows with regard to reaction principle:
Calcium ion in the reaction system at first with EDTA ion Y
4-React, generate complex compound, calcium ion is sheltered, i.e. Ca
2++Y
4-→ CaY
2-
Add stoichiometric phosphate anion then, under alkaline condition, add proper amount of oxidant, make system even.The reacting by heating system, oxygenant destroys Ca
2+ ion with the phosphate radical reaction, because of its concentration reaches supersaturation simultaneously everywhere in whole system, forms the homogeneous reaction condition, thereby generates spherical precipitation.
Reaction principle and EDTA with ethylenediamine tetraacetic acid (EDTA) are identical, and citric acid is similar to EDTA to the action principle of its salt, just the calcium complex difference that generates.
The consumption of EDTA etc. can add by stoichiometry, is sign not occur muddiness in the solution.Oxygenant should be used hydrogen peroxide.Its add-on is being as the criterion by the completely destroy complex compound.
Among the present invention, the calcium salt that the compound that calcium ion is provided is nitrocalcite, calcium chloride, the lime acetate water solubility is big, the also calcium cpd of available poorly water-soluble, as calcium oxide, calcium hydroxide, lime carbonate etc., but use with acid dissolving back earlier.The most suitable concentration of calcium ion is in the reaction system: 0.0001～3.5mol, and in general, concentration is lower, and particle is bigger, when concentration is higher than 3.5mol, is not easy to control the homogeneous reaction condition.
Among the present invention, the compound that phosphate anion is provided is phosphoric acid or phosphatic water-soluble salt, as Sodium phosphate dibasic, dipotassium hydrogen phosphate, SODIUM PHOSPHATE, MONOBASIC, potassium primary phosphate, primary ammonium phosphate, Secondary ammonium phosphate, trisodium phosphate, tetra-sodium, tripoly phosphate sodium STPP, phosphoric acid etc., the most suitable concentration when reaction is 0.0001～3.5mol/l, and in general, concentration is lower, particle is bigger, when concentration is higher than 3.5mol/l, salt out, be not easy to control the homogeneous phase reaction conditions.
In the hydroxyapatite molecular composition, the mol ratio of calcium and phosphorus is 1.67, but when precipitation from homogeneous solution (PFHS) reacted, its ratio can suitably change up and down.
Calcium ion and phosphate anion precipitin reaction may generate the calcium phosphate salt of the outer various ways of hydroxyl-removal phosphatic rock.
The present invention does not relate to granulation process, can directly prepare ball shaped hydroxy-apatite.Ball shaped hydroxy-apatite is good liquid chromatography packing material, and other gives birth to the body material also to be used for artificial dentistry and orthopaedics etc.
Positively effect of the present invention:
1. adopt the present invention can prepare 3～5um, 5～20um, 20～60um, and the spheroidal particle of 60～100um are applicable to the filled media of the post of liquid chromatography.The appearance of the ball shaped hydroxy-apatite of employing the present invention preparation as shown in Figure 1.
2. the x-ray diffraction pattern of the ball shaped hydroxy-apatite of the present invention's preparation as shown in Figure 2.From figure as can be seen, spheroidal particle is a hydroxyapatite crystal.
With the color atlas of the ball shaped hydroxy-apatite packing protein isolate quality sample of the present invention preparation shown in Fig. 3 b, monoclonal antibody separation chromatography in the mouse ascites fluid is compared with the chromatographic column separation chromatography of filling with sheet-shaped hydroxyapatite (Bio Rad company product is shown in Fig. 3 a) under the parallel condition, effect will be got well, and the peak of latter's monoclonal antibody does not obviously separate.
4. can prepare various spherical calcium phosphate compounds with the inventive method, as compounds such as octocalcium phosphate, alpha-calcium phosphate, beta-calcium phosphate, amorphousness calcium phosphate, dicalcium phosphate dihydrate, calcium phosphate dibasic anhydrouses.
Provide the specific embodiment of the invention below.
A kind of precipitation from homogeneous solution (PFHS) prepares the method for ball shaped hydroxy-apatite, it is characterized in that: in the aqueous solution that contains certain density calcium ion and phosphate anion, add precipitation agent or network and agent and oxygenant generation homogeneous reaction, under certain reaction conditions, generate spherical precipitation.
Its example 1: the mol ratio of reagent calcium ion and phosphate anion is: 1.5; Precipitation agent is: urea or hexamethylenetetramine, and the concentration of precipitation agent is: 0.002mol/l; The concentration of precipitation from homogeneous solution (PFHS) reagent is: 0.0002mol/l, temperature of reaction is: 50 ℃, the reaction times is: 10 minutes.
Its example 2: the mol ratio of reagent calcium ion and phosphate anion is: 1.5; Network and agent are: ethylenediamine tetraacetic acid (EDTA) or EDTA or citric acid, and Citrate trianion, complexing agent concentration should equate or high slightly with calcium ion concn during reactant is adopted; Oxygenant is: hydrogen peroxide, and oxidant concentration is: 5%; The concentration of precipitation from homogeneous solution (PFHS) reagent exists: 0.0002mol/l, temperature of reaction is: 75 ℃, the reaction times is: 10 minutes.
Embodiment 1
The calcium chloride solution 50ml of 3mol/l and the disodium phosphate soln 50ml of 1.5mol/l are joined in the flask of 1000ml, water is diluted to 800ml, stir well even, adding urea degree of depth of urea to the reaction system is 3mol/l, stir evenly, heating is 40 minutes in 75 ℃ water-bath, takes out flask, the middle cooling that discharges water, the spherical particle that filtration washing obtains.
Embodiment 2
The ca nitrate soln 50ml of 3mol/l and the dipotassium hydrogen phosphate solution 50ml of 1.5mol/l are joined in the flask of 1000ml, water is diluted to 800ml, stir well even, adding hexamethylenetetramine concentration of hexamethylenetetramine to the reaction system is 3.5mol/l, stir evenly, heating is 240 minutes in 45 ℃ water-bath, takes out flask, the middle cooling that discharges water, the spherical particle that filtration washing obtains.
Embodiment 3
The ca nitrate soln 50ml of 3mol/l and the phosphoric acid dioxy ammonium solution 50ml of 1.5mol/l are joined in the flask of 1000ml, water is diluted to 800ml, stir well even, adding urea concentration of urea to the reaction system is 10mol/l, stir evenly, heating is 40 minutes in 75 ℃ water-bath, takes out flask, the middle cooling that discharges water, the spherical particle that filtration washing obtains.
Embodiment 4
In the flask of 1000ml, the calcium acetate solution 50ml that adds 3mol/l, the EDTA solution 300ml of adding 0.5mol/l stirs evenly, the sodium dihydrogen phosphate 60ml water that adds 1.5mol/l then is diluted to 800ml, stir well evenly, add 30% hydrogen peroxide 100ml, stir evenly, heating is 45 minutes in 80 ℃ water-bath, take out flask, the middle cooling that discharges water, the spherical particle that filtration washing obtains.
Claims (3)
1, a kind of precipitation from homogeneous solution (PFHS) prepares the method for ball shaped hydroxy-apatite, it is characterized in that: in the aqueous solution that contains certain density calcium ion and phosphate anion, add precipitation agent or network and agent and oxygenant generation homogeneous reaction, under certain reaction conditions, generate spherical precipitation.
2, precipitation from homogeneous solution (PFHS) according to claim 1 prepares the method for ball shaped hydroxy-apatite, it is characterized in that: the mol ratio of reagent calcium ion and phosphate anion is: 1.2～4.5; Precipitation agent is: urea or hexamethylenetetramine, and the concentration of precipitation agent exists: 0.001～10mol/l; The concentration of precipitation from homogeneous solution (PFHS) reagent is at 0.0001～3mol/l, and temperature of reaction is between room temperature to 400 ℃, and the reaction times is between 5 minutes to 20 hours.
3, precipitation from homogeneous solution (PFHS) according to claim 1 prepares the method for ball shaped hydroxy-apatite, it is characterized in that: the mol ratio of reagent calcium ion and phosphate anion is: 1.2～4.5; Network and agent are: ethylenediamine tetraacetic acid (EDTA) or EDTA or citric acid, and Citrate trianion, complexing agent concentration should equate with calcium ion concn in the reaction system or be high slightly; Oxygenant is: hydrogen peroxide, and oxidant concentration is: 1～20%; The concentration of precipitation from homogeneous solution (PFHS) reagent is at 0.0001～3mol/l, and temperature of reaction is between room temperature to 400 ℃, and the reaction times is between 5 minutes to 20 hours.
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| CN1299369C (en) * | 2005-01-06 | 2007-02-07 | 清华大学 | Method for preparing high-density spherical lithium iron phosphate |
| CN100336719C (en) * | 2006-03-28 | 2007-09-12 | 成都迪康中科生物医学材料有限公司 | Hydrothermal process of preparing nanometer hydroxyapatite colloid |
| WO2007133104A1 (en) * | 2006-05-17 | 2007-11-22 | Igor Anatolievich Pomytkin | Hydroperoxylapatite and compositions thereof |
| CN101407316B (en) * | 2007-10-12 | 2012-05-09 | 西南交通大学 | Method for preparing high dispersibility nano-hydroxyapatite |
| CN103088383A (en) * | 2011-11-04 | 2013-05-08 | 电子科技大学 | Electrochemical method for preparing citric acid-hydroxyapatite/zirconia transition coating on surface of biomedical titanium |
| CN103159198A (en) * | 2013-04-09 | 2013-06-19 | 厦门合众思创生物工程有限公司 | Preparation method of calcium phosphate |
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| CN106966377A (en) * | 2017-04-07 | 2017-07-21 | 上海静妤生物科技有限公司 | Hydroxyapatite micro-sphere and preparation method thereof |
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| CN111247093A (en) * | 2017-10-20 | 2020-06-05 | 株式会社秀顿斯 | Preparation method of octacalcium phosphate and octacalcium phosphate prepared by same |
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|---|---|---|---|---|
| GB2025912A (en) * | 1978-07-21 | 1980-01-30 | Spencer M | Process for preparing a crystalline form of calcium phosphate |
| JPS60143762A (en) * | 1983-10-03 | 1985-07-30 | Mitsui Toatsu Chem Inc | Hydroxy apatite for chromatography |
| WO1986003733A1 (en) * | 1984-12-18 | 1986-07-03 | Kanto Kagaku Kabushiki Kaisha | Calcium-phosphorus type apatite having novel properties and process for its production |
| JPH0624964B2 (en) * | 1985-09-23 | 1994-04-06 | 東燃株式会社 | Calcium phosphate-based hydroxyapatite and method for producing the same |
| US4849193A (en) * | 1988-05-02 | 1989-07-18 | United States Gypsum Company | Process of preparing hydroxylapatite |
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| CN1299369C (en) * | 2005-01-06 | 2007-02-07 | 清华大学 | Method for preparing high-density spherical lithium iron phosphate |
| CN100336719C (en) * | 2006-03-28 | 2007-09-12 | 成都迪康中科生物医学材料有限公司 | Hydrothermal process of preparing nanometer hydroxyapatite colloid |
| WO2007133104A1 (en) * | 2006-05-17 | 2007-11-22 | Igor Anatolievich Pomytkin | Hydroperoxylapatite and compositions thereof |
| CN101407316B (en) * | 2007-10-12 | 2012-05-09 | 西南交通大学 | Method for preparing high dispersibility nano-hydroxyapatite |
| CN101855168B (en) * | 2007-11-12 | 2014-05-21 | Hkpb科技有限公司 | A combustion process for the manufacture of calcium phosphate and calcium phosphate composite particles |
| CN103088383A (en) * | 2011-11-04 | 2013-05-08 | 电子科技大学 | Electrochemical method for preparing citric acid-hydroxyapatite/zirconia transition coating on surface of biomedical titanium |
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| CN105293461B (en) * | 2015-11-18 | 2017-08-29 | 湖北工业大学 | A kind of preparation method of Oil soluble hydroxy apatite nanometer sheet |
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