Method of receiving of nano-crystalline calcium hydroxyapatite

FIELD: nanotechnology.

SUBSTANCE: invention relates to method of receiving of nano-crystalline hydroxyapatite. According to the invention calcium nano-crystalline hydroxyapatite is received by interaction of compound of calcium and ammonium hydro-phosphate. In the capacity of calcium compound it is used sugar lime C12H22-2nO11Can, at n, which is situated in the range from 0.5 up to 2. Particles size of the received hydroxyapatite is 30-50 nm.

EFFECT: receiving of nano-crystalline powder of calcium hydroxyapatite, which contains unaggressive biocompatible accompaniment of the reaction and that provides its usage in medicine.

3 dwg, 1 tbl, 1 ex

 

The invention relates to methods for producing powders of calcium hydroxyapatite (HAP), which can be used in medicine.

Known methods for producing gap, in which the starting compounds using ammonium phosphate and calcium nitrate (1) or ammonium phosphate and calcium chloride (2). The disadvantages of these methods is the inability to completely remove a byproduct ammonium nitrate or ammonium chloride by washing, which makes this powder is corrosive to body tissues when used as a filler for bone defects or as a carrier of drugs.

A method of obtaining gap, in which the starting components used calcium chloride and sodium phosphate (3). The disadvantage of this method is the use of boiling in alkali, which results in coarse powder.

Closest to the proposed invention is a method (4) receipt of HAP powder that does not contain corrosive by-product credits, in which the starting compounds used calcium oxide and ammonium phosphate. The disadvantage of this method is to obtain coarse powder gap, which is caused by the synthesis of the interaction of components in the solid phase, as well as the use of high temperature is processing at high (950°C) temperature.

The aim of the present invention was to obtain nanocrystalline HAP powder containing biocompatible non-aggressive co-product of the reaction.

In a method of producing nanocrystalline HAP powder as starting compounds used saharat calcium12H22-nAbout11CAnand ammonium phosphate.

The solution saharat calcium is prepared by the interaction calcined at 1000°C the oxide of calcium and sucrose solution according to reaction (1).

The value of n for this reaction range from 0.5 to 2. Lower values of n lead to a significant increase in the number of sucrose to conduct synthesis without significant effect on the particle size of the product. For n greater than 2, in solution form insoluble saharty calcium, while carrying out the synthesis of the gap leads to the formation of multiphase product, containing, along with the gap unreacted source component - saharat calcium.

To the obtained saharat calcium added dropwise a solution of ammonium hydrogen phosphate with constant stirring at room temperature in accordance with reaction (2).

Then transform the obtained gel of amorphous calcium phosphate in suspension NANOKRISTALLIChESKOGO gap the reaction mixture is heated up to T=60°C. the Obtained suspe is the Zia filter, the filter cake is dried in a thin layer.

According to x-ray analysis of the powder contains nanocrystalline HAP powder (Figures 1-3). The particle size of the gap is 30-50 nm.

The invention is illustrated in the figures and example.

Figures

Figure 1. Data of x-ray phase analysis for the powder synthesized from ammonium hydrogen phosphate and saharat calcium C12H21O11Ca0.5.

Figure 2. Data of x-ray phase analysis for the powder synthesized from ammonium hydrogen phosphate and saharat calcium12H20About11Sa (Example).

Figure 3. Data of x-ray phase analysis for the powder synthesized from ammonium hydrogen phosphate and saharat calcium C12H18O11Ca2.

Example

To 28,04 g pre-calcined at 1000°C Cao was added to 1 l of an aqueous solution of sucrose in which it was contained 171,05, the ratio of calcium oxide and sucrose produces a clear solution adenocarcinoma (n=1) saharat C12H20O11Ca. To the resulting solution saharat, having a pH of at least 12 was added dropwise 0.5 m solution of ammonium hydrogen phosphate. Interaction according to reaction (3) resulted in the formation of a stable gel, and after heating to 60°With the formation of stable to sedimentation of suspensions of nanocrystalline HAP in rasterisers.

Data of x-ray phase analysis confirm the formation of nanocrystalline HAP with a particle size of 30-50 nm.

Similarly, were synthesized powders NANOKRISTALLIChESKOGO gap from saharat calcium hydrogen phosphate and ammonium when changing n from 0.5 to 2 (table). The table shows that with these changes the values of n in the saharat calcium C12H22-2nO11Canwhen performing synthesis on the proposed method formed nanokristallichesky gap with particle size of 30-50 nm. The byproduct of the reaction is saharat ammonium decompose ammonia and sucrose. Sucrose is a substance not corrosive to body tissues.

Table
No.The value n in the saharat calcium C12H22-2nO11CanThe particle size of the gapThe phase composition of the target productShapes
10,530-50 nm100% hydroxyapatite1
21,030-50 nm 100% hydroxyapatite2
32,030-50 nm100% hydroxyapatite3

Thus, the experimental data show that the use of the claimed method allows to obtain nanocrystalline HAP powder that does not contain corrosive to tissues of a living organism byproduct.

Literature

1. Vasilikou, Iperu, Vaikasi, Namechina, Maagazine, Sycheva VY Patent RU 2038293, 26.06.1992. The method of obtaining hydroxyapatite.

2. Astaman, Oueration, Grabelnikova, Timetrack, Genealogia, Limasexadriana. Copyright certificate 710928. 25.01.1980. The method of obtaining calcium hydroxylapatite.

3. Ulitize, Sdhedule, Spiglazova and Aggripina. Inventor's certificate SU 1450852, 07.01.1987. A method of producing a sorbent-hydroxyapatite.

4. Vpolicy, Havronicheva, Gaiola, Gesheva, Emoval and Namerow. Patent SU 1834836, 26.11.1991. The method of obtaining calcium hydroxylapatite.

The method of obtaining nanocrystalline hydroxyapatite calcium interaction calcium hydrogen phosphate and ammonium, wherein as calcium use saharat calcium C12H22-2nO11Canwhen n, lying is m in the interval from 0.5 to 2.



 

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