JPH0426509A - Hydroxyapatite fine crystal and its production - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a fine delivery of hydroxyapatite and a method for producing the same, and more specifically to a stationary phase agent packed in a column for column chromatography, a carrier material for cell culture and separation This invention relates to hydroxyapatite microcrystals useful as bio-related materials such as, and a method for producing the same.

<Prior art> Hydroxyapatite (hereinafter referred to as HAP) crystal particles have conventionally been used as a stationary phase agent packed in a column for column chromatography, and have excellent chromatographic separation performance (substance separation development performance).
It is used as an essential material for high-purity separation and purification of substances in the biotechnology field.

The HAP particles and their manufacturing method are described in Japanese Patent Application Laid-Open No. 1983-1999.
In Publication No. 202808, the monetite suspension water obtained by heating the suspension water of purushite crystal particles in the range from the dehydration phase transition temperature to the boiling point of the suspension water and causing the dehydration phase transition to be boiled by applying an alkali to the monetite suspension water, A method has been proposed for synthesizing plate-like HAP crystal particles that retain the shape of the starting material, the Pruscheite crystal particles. however.

In all of the composites obtained by the above methods, only multi-crystalline aggregates of HAP crystal particles are obtained, and the morphology of the HAp primary particles constituting the aggregates is not controlled.
Stationary phase agent packed in the column.

When used as a carrier material for cell culture/separation, etc.

The drawback is that highly accurate substance separation and development performance cannot be obtained.

Furthermore, in JP-A No. 61-242968, a method is proposed in which hexagonal columnar HAp crystal particles are synthesized by applying pressure and carrying out a hydraulic reaction using an autoclave. The particles are hexagonal columnar primary particles with an aspect ratio of 2.5 to 3.0,
The HAP crystal particles are the same in shape as the HAp particles obtained by calcining the HAp precursor obtained by wet synthesis at around 800°C, and therefore the primary particles are HAp particles whose shape is more precisely controlled. Development of crystalline particles is desired.

<Problems to be Solved by the Invention> The purpose of the present invention is to provide HAp microcrystalline particles that precisely control the shape of primary particles and have higher precision substance separation and development ability, and a method for producing the same. be.

According to the present invention, a calcium phosphate compound slurry adjusted to pH=10 or higher or a calcium phosphate compound slurry containing an additive is subjected to hydrothermal treatment under saturated steam pressure at a temperature higher than the boiling point of the slurry solvent. Microcrystalline hydroxyapatite having an aspect ratio (c/a) of less than 2.0 is provided.

Further, according to the present invention, the pH of the calcium phosphate compound slurry is adjusted to 10 or higher, or the calcium phosphate compound slurry containing an additive is hydrothermally treated under saturated steam pressure at a temperature higher than the boiling point of the slurry solvent. Obtained aspect ratio (c/a)2.
A method for producing hydroxyapatite microcrystals of less than 0 is provided.

The present invention will be explained in more detail below.

The HAp microcrystal of the present invention can be produced by a specific method.
Preferably, it is a plate-shaped crystal characterized by having a specific aspect ratio.

In the present invention, 1, for example, stationary phase agent packed in a column, cell culture,
When used as a separation carrier, the aspect ratio (c
/a) is less than 2.0. When the aspect ratio is 2.0 or more.

When used as a stationary phase agent packed in a column, there is a risk that the adsorption rate characteristics will decrease.

In addition, the lengths of the a-axis and all in the HAP microcrystals of the present invention are set such that the length of the crystals in the a-axis direction is set to facilitate the penetration and to prevent clogging when used as a stationary phase agent packed in a column. 10~1100n.

The length of the crystal in the C-axis direction is preferably 1 to 200 nm.

Next, the manufacturing method of the HAp microcrystal of the present invention will be explained in more detail.

To fabricate the HAp microfine product of the present invention, first.

A calcium phosphate compound slurry adjusted to pH=10 or higher, preferably pH=12 or higher, or a calcium phosphate compound slurry containing an additive is g*. The pH=10
The calcium phosphate compound slurry prepared above was
For example, a slurry is obtained by wet-synthesizing Ca(OH), H, and PO2 by a known method.
It can then be obtained by adding a pH adjuster such as aqueous ammonia. At this time, the weight ratio of the calcium phosphate compound and water in the slurry is 1:1 to 1.
Preferably, it is in the range of 00. When the pH of the calcium phosphate compound slurry is less than 10, C
It is not possible to suppress the elution and precipitation of constituent ions necessary for the growth of the axis, and it is not possible to adsorb hydroxide ions to the C-plane and increase the relative growth rate of the a-axis.

In the present invention, the C-plane of a microcrystal is defined as a
This is a surface determined by defining the surface determined by the axis and the b-axis as the C surface.

On the other hand, apart from this, additives are added and the aspect ratio (c
It is also possible to obtain fine crystals with /a) of less than 20. A calcium phosphate compound slurry containing the additive can be prepared by adding the additive during, after, or both during and after the preparation of the calcium phosphate compound. As the additive, HAp fine crystal C
Any additive may be used as long as it is capable of adsorbing anions on the surface, dissolving crystals in the C-axis direction, or accelerating the growth rate of the a-axis, or has these effects.Specifically, for example, Preferred examples include chloride salt compounds such as potassium chloride and sodium chloride, and sulfate compounds such as potassium sulfate and sodium sulfate. At this time, the amount of additive added is 1 for the calcium phosphate compound slurry.
The amount is preferably in the range of 0.1 to 50 parts by weight per 00 parts by weight.

To produce HAp microcrystals, then the pH=10
The calcium phosphate compound slurry prepared above or the calcium phosphate compound slurry containing the additive is heated at a temperature of at least 100% to a boiling point of the slurry solvent.
At 300°C.

Under saturated vapor pressure, preferably 0.1 to 2 OM Pa.

It can be obtained by hydrothermal treatment. The hydrothermal treatment may be performed using a known autoclave or the like under the conditions described above, and more preferably, by performing the hydrothermal treatment for 0.1 to 24 hours, HAp@fine crystals having a desired aspect ratio can be obtained. If the reaction temperature in the hydrothermal treatment is lower than the boiling point temperature of the slurry solvent, the reaction will not proceed.

Further, if the pressure is less than the saturated vapor pressure, crystallinity will not improve.

The HAP microcrystals of the present invention can be used after being purified by a known method if necessary.

<Effects of the Invention> The HAP microcrystals of the present invention are produced by a specific method,
The aspect ratio (c/a) is less than 2.0, and more calcium sites are present on the surface.*m The C-plane of the crystal is grown in a stacked manner, exposing a relatively large amount of calcium sites. It is possible to selectively increase the separation or culture efficiency of biochemical substances, cells, etc. that have an affinity for, and therefore, it is extremely useful as a stationary phase agent packed in a column, a carrier material for cell culture/separation, etc. In addition, in the production method of the present invention, H
Since Ap fine crystals can be obtained, it is extremely useful industrially.

<Examples> The present invention will be described in more detail below with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

A 10% by weight slurry of a calcium phosphate compound was obtained by wet synthesis of 1J Li Ca (OHL, 85% by weight H, and P04).

To 500 mQ of the obtained Rinsan calcium compound slurry, pH II Add and dissolve ammonia water as a preservative, P
It was adjusted to H=10.12.

Each slurry obtained was then filled into an autoclave,
Hydrothermal treatment was performed at 200° C., 2 MPa, and for 5 hours. After completion of the treatment, each of the obtained slurries was washed with distilled water IQ, filtered, and then dried at 100° C. in a drier.

When the shape of the obtained hydroxyapatite microcrystals was analyzed by X-ray analysis, it was found that when the crystallite diameter was pH=10, the crystal length in the a-axis direction was 80 nm, the crystal length in the C-axis direction was 50 nm, and the aspect ratio ( c/a) = 1
,6.

At PH=12, it was a plate-like single crystal with a length in the a-axis direction of 50 nm, a length in the c-axis direction of 50 nm, and an aspect ratio (c/a) of 1.0.

Example 1 was carried out in the same manner as in Example 1, except that 5 g of CQ was added and mixed into the additive instead of pH 5 l aqueous ammonia. Crystal length of 80 nm + 7 spectral ratio (c/a)
A plate-shaped HAp single crystal with a diameter of 1.8 was obtained.

Item 11 pHI in calcium phosphate compound slurry! The crystallite diameter was 50 nm, the crystal length in the a-axis direction, in the same manner as in Example 1, except that no conditioner or additive was added.

A hexagonal columnar HAp single crystal with a crystal length in the C-axis direction of 140 nm and an aspect ratio (c/a) of 2.8 was obtained.

The dried HAp fine crystals obtained in Examples 1 and 2 (microcrystals obtained using a slurry with pH = 12) and Comparative Example 1 were each crushed and classified to form agglomerated powders of 144 μm or less. did. As a binder, the product name "Maxelon" (manufactured by Shin-Etsu Chemical Co., Ltd.) was applied to the powder for 5 minutes.
After addition and mixing in weight percent, the mixture was press-molded using a mold, and then crushed and classified to obtain granules with a caliber diameter of 0.3 to 0.5 square meters. Furthermore, the obtained granules were placed in an electric furnace at 900°C for 3 hours at a temperature increase/decrease rate of 5°C.
/ min, and the column packing material for cell culture was baked at 2 min.
I got 5g. Each 3-column volume was filled with this packing material, and 1 to Q of a cell suspension (approximately 105 to 106 cells) of mouse calvaria-derived bone material cells MC3T3-El was charged into the column. Next, the column was made into a closed system, and a pump was used to flow the medium at an elution rate of 5El!1/min using α-MEM (trade name, manufactured by Hazelton) as a developing solvent.10mQ of the medium eluted from the column was poured into a small The adsorption rate was calculated from the number of eluted cells collected in a test tube and counted using a hemocytometer (manufactured by Kayagaki Seisakusho).The results are shown in Table 1.
From the results, the adsorption rate characteristics as a column packing material for cell culture are inversely proportional to the aspect ratio (c/a), that is, a
It was found that it increases in proportion to the effective area of the plane or b-plane.

(Margin below) Table-1

Claims (1)

[Claims] 1) Calcium phosphate compound slurry adjusted to pH=10 or higher at a temperature higher than the boiling point of the slurry solvent,
Aspect ratio (c) obtained by hydrothermal treatment under saturated steam pressure
/a) Hydroxyapatite microcrystals less than 2.0. 2) Calcium phosphate compound slurry containing additives,
Aspect ratio (c/a) 2.0 obtained by hydrothermal treatment under saturated steam pressure at a temperature above the boiling point of the slurry solvent
Less than hydroxyapatite microcrystals. 3) Set the pH of the calcium phosphate compound slurry to pH=
10 or higher, and hydrothermal treatment under saturated steam pressure at a temperature equal to or higher than the boiling point of a slurry solvent. 4) A method for producing hydroxyapatite microcrystals having an aspect ratio (c/a) of less than 2.0 obtained by hydrothermally treating a calcium phosphate slurry containing an additive under saturated steam pressure at a temperature equal to or higher than the slurry boiling point.