KR100991099B1 - Silica xerogel physiologically active organic substance hybrid composites and preparation method thereof - Google Patents

Abstract

The present invention provides an organic / inorganic hybrid composite having a silica-based silica gel (silica xerogel) bioactive organic material having excellent biocompatibility and a method for preparing the same.

The present invention also relates to a hard tissue regeneration, transplantation or replacement material including an organic / inorganic hybrid complex in which silica-based xerogel physiologically active organic matter is bound; Or a carrier for drug delivery.

In the present invention, by using a solgel (Solgel) method for synthesizing the inorganic material at room temperature, it is possible to provide a biomedical organic-inorganic complex having excellent biological properties without additional heat treatment.

Biomaterials, Sol-Gel Method, Hybrid

Description

SILICA XEROGEL PHYSIOLOGICALLY ACTIVE ORGANIC SUBSTANCE HYBRID COMPOSITES AND PREPARATION METHOD THEREOF}

The present invention provides a method for preparing an organic / inorganic hybrid composite using the sol-gel method, and a bio-medical silica zero gel bioactive organic composite hybrid having a superior bio-characteristic prepared by the method, preferably silica zero gel chitosan ( chitosan) hybrid composites.

 As the ratio of organic matter is the highest among the substances constituting the human body, bio-organic materials take up a large proportion in the study of biomaterials. Among them, chitosan is a representative bio-organic material used for various studies such as wound healing, drug delivery, and coating because it is suitable as a natural bio-organic material, is inexpensive, and has various characteristics such as water solubility. However, because of low bioactivity, many researches have been made to overcome this problem.

On the other hand, since the hard tissue of the human body is composed of a composite of organic fibers and inorganic nanoparticles, it can be said that the development of organic-inorganic nano-composite technology in the development of biomaterials for hard tissue replacement is the ultimate challenge. In the design of organic-inorganic hybrid nanomaterials that mimic human bone tissue, technology is needed to improve or overcome the problems of current technology by introducing nanotechnology, and not to discover new materials that require huge capital and time. The introduction of material technology is of significant value in developing biomimetic artificial bones. Until now, many efforts have been made to develop organic-inorganic hybrid composites at home and abroad, but inorganic materials are basically materials that require heat treatment, and this problem must be solved in order to complex with organic materials that are relatively weak in heat.

Accordingly, many studies using coprecipitation or sol-gel method have been conducted to prepare an organic / inorganic hybrid composite. However, sol-gel method used in the preceding experiments is silane or siloxane in organic matter. The back is first mixed with an organic material to form a complex of organic material and silicon (Si) or used for crosslinking of the organic material. In addition, the microstructure and various biological properties of the materials produced by these studies are rarely clearly presented. Therefore, there is an urgent need for an organic / inorganic hybrid composite having various biological characteristics and a manufacturing method satisfying their manufacturing characteristics.

It is an object of the present invention to provide a biomedical organic-inorganic hybrid composite having excellent homogeneity, fineness, and biocompatibility without a separate heat treatment, and a method of manufacturing the same.

The present invention is based on this.

The present invention is an organic / inorganic hybrid composite comprising (a) a silica xerogel and (b) a physiologically active organic compound, wherein the physiologically active organic material is a three-dimensional network in the surface of the zero gel or in the zero gel. Provided is an organic / inorganic hybrid composite characterized by uniform distribution on (networked) pores.

In this case, the physiologically active organic material may be chitosan, a natural polymer, or a synthetic polymer.

The present invention also provides a material for hard tissue regeneration, transplantation or replacement comprising the organic / inorganic hybrid complex.

Furthermore, the present invention provides a carrier for drug delivery comprising the organic / inorganic hybrid complex.

In addition, the present invention comprises the steps of (a) preparing a silica zero gel appetizer by mixing and stirring the silicate, catalyst, distilled water; (b) mixing the physiologically active organic material in a liquid state to the silica zero gel appetizer prepared in step (a) to form a hybrid material; And (c) neutralizing and drying the liquid hybrid material to prepare an organic / inorganic hybrid composite.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

In the present invention, using the room temperature sol-gel method has a nano-scale uniform microstructure and characterized in that the organic / inorganic hybrid composite having excellent biological properties.

The organic / inorganic hybrid composite of the present invention may largely include a silica-based zero gel and a bioactive organic material.

The xerogel is a kind of porosity glass material and may be prepared according to a method of forming a porous polymer through a specific solvent reaction. The zero gel has a complicated three-dimensional network of pore structures in nano units, and it is possible to collect and distribute bioactive organic substances uniformly in the pores of the zero gel, part or all of the surface thereof. It can show the structural and physical stability of the final organic / inorganic hybrid composite.

That is, the organic / inorganic hybrid composite of the present invention not only promotes structural stability and ease of manufacture by using zero gel as an inorganic component, but also stably and continuously exerts excellent biocompatibility by bioactive organic substances that are firmly bound to zero gel. Can be.

In addition, in the present invention, not only various natural and synthetic organic materials may be applied as bioactive materials without limitation, but also various biomedical fields may be applied based on various biological properties of the applied organic materials. In particular, the materials of the present invention are expected to contribute to the field of related hard tissue regenerative medicine while addressing the needs of various hard tissue replacements with soft tissues, transplantation and drug delivery (DDS) for damaged hard tissue regeneration, and bone replacement materials.

The zero gel of the present invention is not particularly limited as long as it can uniformly distribute and firmly bind the bioactive substance. Preferably it is a silica type zero gel.

Silica zero gel refers to an inorganic material that forms a silicate structure formed through the step of hydrolysis condensation of metal alkoxides [M (OR) ₄ : M = Si]. Such silica zero gel can be easily prepared by mixing raw material reagents at room temperature by the sol-gel method, and easily removing components other than silicates, such as ethanol, methanol, water, etc., by drying and washing. There is this.

The silica-based zero gel may be an aluminum silicate hydrate containing an element selected from alkali metals and alkaline earth metals, wherein Ca, P, Ga, Ge, Fe, Zr, Ti, Cr, B, Be, V It is preferably substituted by an atom selected from the group consisting of, Zn and As. In order to increase biocompatibility, silica-based zero gels containing Ca and / or P are more preferable. This is because the minerals that make up hard tissues are generally calcium phosphate-based, so if the biomaterials of the present invention contain calcium phosphate-based, Ca and / or P components, the implanted material reacts with body fluids to regenerate hard tissues (e.g., new bone). This can be derived faster.

The size (particle diameter), porosity and / or pore size of the silica zero gel is not particularly limited, and may be appropriately adjusted within a range capable of exhibiting excellent biocompatibility and structural stability.

According to the present invention, the component forming the hybrid complex with the zero gel is not particularly limited as long as it is an organic component showing bioactivity.

Non-limiting examples of bioactive substances that can be used include chitosan, gelatin, collagen, starch, polylactide (PLA), polyglycolide (PGA), polycaprolactone ( PCL), poly (caprolactone lactide) random copolymer (PCLA), poly (caprolactoneglycolide) random copolymer (PCGA), poly (lactideglycolide) random copolymer (PLGA), poly Ethyl oxide (PEO), polyethylglycol (PEG) or mixtures of one or more thereof. In particular, chitosan is preferable. In addition to the above-mentioned ingredients, organic substances which can be supported on a zero gel to be biocompatible are also within the scope of the present invention.

In the organic / inorganic hybrid composite according to the present invention, the component ratio of the silica zero gel and the bioactive organic compound may be in the range of 10 to 95:90 to 5 (vol%), preferably 10 to 40:90 to 60 (vol%). ) Range. However, it is not limited thereto. At this time, if the content of the physiologically active organic material is too high, biocompatibility may be insignificant, and if the content of zero gel is too high, the mechanical properties of the final organic / inorganic hybrid composite may be reduced.

In addition to the aforementioned components, the organic / inorganic hybrid composite of the present invention may include other components or additives commonly used.

The organic / inorganic hybrid composite of the present invention can be prepared using a room temperature solgel (solgel) method using a silica zero gel and a bioactive material.

Particularly, in the present invention, the two liquid organic inorganic materials are mixed at room temperature and synthesized by a sol-gel method. Unlike the conventional method, before the organic and inorganic materials are mixed, the raw material reagents of the inorganic materials are mixed in advance to hydrolyze the silica zero gel. It is characterized by first inducing to produce a composite comprising a fine silica structure.

For one preferred embodiment of the production method, (a) preparing a silica zero gel antagonist by mixing and stirring the silicate, catalyst, distilled water; (b) mixing the chitosan solution prepared in the silica zero gel appetizer prepared in step (a) in a liquid at a predetermined ratio to form an organic / inorganic hybrid material; And (c) neutralizing and drying the liquid hybrid material to prepare an organic / inorganic hybrid composite.

First, silicate, a catalyst, and distilled water are mixed to prepare a silica zero gel appetizer.

The silicate may use a silicate compound known in the art, non-limiting examples thereof include tetraethoxysilane (TEOS), tetramethoxysilane (TMOS) and the like. In addition, the catalyst is preferably an acid catalyst such as an acid, but is not limited thereto. In this case, the acidity of the silica zero gel precursor may be appropriately adjusted within a conventional range in the art according to the form to be prepared or required properties.

In this case, in order to prepare a silica zero gel containing calcium and phosphorus, it is preferable to add silica and phosphorus and stir until gelation occurs to prepare a silica zero gel appetizer. The composition ratio of the preferred silica zero gel appetizers ranges from 80 to 100 parts by weight of silicate, 0 to 15 parts by weight of calcium-containing precursor compound and 0 to 5 parts by weight of phosphorus-containing precursor compound, based on 100 parts by weight of the total appetizer. to be.

Thereafter, a physiologically active organic material, such as a chitosan solution, is added to the silica zero gel appetizer, followed by mixing to prepare a liquid composite for preparing a silica zero gel bioactive organic compound hybrid composite. At this time, the component ratio of the silica zero gel and the physiologically active organic material may be in the range of 10 to 95:90 to 5 (vol%), and preferably in the range of 10 to 40:90 to 60 (vol%).

Neutralize to neutral using the prepared liquid composite, and then precipitate the composite to wash and dry to obtain an organic / inorganic hybrid composite. At this time, the washing and drying process may use a conventional method known in the art.

In fact, the method for producing the organic / inorganic hybrid composite of the present invention is all made at room temperature and does not generate excessive heat during the process, it is suitable for manufacturing a hybrid composite using an organic material.

The organic / inorganic hybrid composite of the present invention prepared as described above may be used for biomedical purposes. In addition, they may be manufactured in the form of a membrane, a bulk, a shield, a coating, or the like through various processes.

In addition, the present invention provides a membrane, preferably a shielding membrane, comprising a silica zero gel bioactive organic hybrid composite as an organic / inorganic hybrid composite.

The membrane can be obtained, for example, by neutralizing and stirring the liquid silica zero gel chitosan compound described above, followed by precipitation and filtration of the compound, followed by drying and washing, and can be used as a biocompatible membrane. Biocompatibility here means that it does not cause a significantly undesirable reaction to the recipient.

Furthermore, the present invention provides materials for hard tissue regeneration, transplantation or replacement, including silica zero gel-bioactive organic hybrid composites as organic / inorganic hybrid composites.

In this case, the material may include a polymer material, a metal or a ceramic material, in which biosafety and biocompatibility have been confirmed. Non-limiting examples thereof include D, L-lactic acid glycolic acid copolymer, polylactic acid, polylactic acid copolymer, polymethyl methacrylate (PMMA), collagen, hyaluronic acid, calcium phosphate-based ceramic materials, and the like. In addition, other additives, solvents and the like known in the art may be additionally included, and may be used in various forms.

In addition, the present invention (a) silica zero gel bioactive organic hybrid composite; And (b) provides a carrier for drug delivery containing a pharmacological material that can be encapsulated in the complex.

The pharmacological substance that can be encapsulated in the complex is not particularly limited as long as it is a substance for treatment, prevention or diagnosis of a disease. Non-limiting examples thereof include anticancer agents, antibacterial agents, steroids, anti-inflammatory drugs, sex hormones, immunosuppressants, antiviral agents, anesthetics, antiemetics or antihistamines. In addition to the aforementioned components, it may also include conventional additives known in the art such as excipients, stabilizers, pH adjusters, antioxidants, preservatives, binders or disintegrants and the like.

Hereinafter, examples and experimental examples according to the present invention are presented. Since these examples and experimental examples are only intended to present specific examples of the present invention, it should not be understood that the scope of the present invention is limited thereto, and that various other modifications and changes may be possible.

As described above, since the present invention uses a manufacturing method that does not require heat treatment, the present invention can easily achieve complexation of inorganic materials with organic materials that are weak to heat, and has an economical advantage by simplifying the manufacturing process. In addition, the present invention relates to the composite between the silica zero gel and the organic material can be applied together in various biomedical organic materials.

As a result of evaluating through similar biological experiments, the method for preparing an organic-inorganic hybrid composite using the sol-gel method according to the present invention and the silica zero gel inorganic organic composite prepared by the method have excellent biocompatibility and potential for use in hard tissue fields. Has

The present invention has been described above with reference to preferred embodiments, but is not limited thereto, and is interpreted by the appended claims, which are intended to cover many modifications that will be apparent to those skilled in the art without departing from the scope of the present invention. Should be done.

Example  1. Silica Zero Gel Chitosan  Organic / Inorganic Hybrid Composite Manufacturing

Silica zero gel chitosan organic-inorganic composite of the present invention was prepared as shown in FIG. 1 is a view schematically illustrating a process for preparing a silica zero gel chitosan organic-inorganic composite, which is an embodiment of the present invention, and is not limited to the contents shown in the drawings.

A chitosan solution was first prepared to prepare a composite for preparing silica zero gel chitosan organic-inorganic complex. Chitosan solution was made of 5% chitosan solution using an acid solution. Thereafter, TMOS (tetramethyl orthosilicate), water, and catalyst (1N HCl), which are raw material reagents of silica zero gel, were first mixed and stirred for 30 minutes to induce hydrolysis. Silica zero gel appetizer obtained through agitation and the prepared chitosan solution were mixed in a range of 10:90 vol% to prepare a liquid composite for making a silica zero gel chitosan organic / inorganic hybrid composite. The manufacturing method was carried out at room temperature.

Example  2

In order to make silica zero gel containing calcium and phosphorus, except for preparing a whole product of silica zero gel by adding calcium (Ca) and phosphorus (P) after stirring for 30 minutes and stirring until gelation occurred. In the same manner as in Example 1, a liquid composite for preparing silica gel zero chitosan organic / inorganic hybrid composite was prepared.

Example  3

The same method as in Example 1 was carried out except that the silica gel preparation and the chitosan solution were changed to 20: 80% by volume instead of in the range of 10: 90% by volume.

Example  4

The same method as in Example 1 was performed except that the silica zero gel appetizer and chitosan solution were changed to 30: 70% by volume instead of in the range of 10: 90% by volume.

Example  5

The same method as in Example 1 was performed except that the silica zero gel appetizer and the chitosan solution were changed to 40: 60 vol% instead of the 10: 90 vol% range.

Example  6. Shield  Produce

Silica zero gel chitosan composite having the composition ratio shown in Table 1 was prepared, and the liquid composite was slowly added dropwise to 96% ethanol. The mixture was stirred for 2 hours to be sufficiently mixed, neutralized by adding dilute ammonia water to pH 7 and stirred for about 1 hour. The composite was neutralized to remove moisture through filtration, and a silica zero gel chitosan composite shielding membrane was prepared by drying and washing.

Comparative Example 1 Example 1 Example 3 Example 4 Example 5 NAME CTS 1S9C 2S8C 3S7C 4S6C Zero gel 0 10 (% by volume) 20 (% by volume) 30 (% by volume) 40 (vol%) Chitosan 100 (volume%) 90 (% by volume) 80 (% by volume) 70 (vol%) 60 (% by volume)

Comparative example  One

Chitosan alone (pure CTS) was used without using zero gels.

Experimental Example  1. Property evaluation

The surface state, microstructure, and biological properties of the silica zero gel chitosan hybrid composite according to the present invention were performed as follows.

1-1. Surface condition

2 is a scanning electron micrograph showing the surface state of the silica zero gel chitosan hybrid composite prepared according to the present invention. In this case, ⓐ in the organic-inorganic hybrid complex is a case where the content of the zero gel is small and ⓑ is a photograph of the composite having a high content of zero gel.

As shown in FIG. 2, the surface (pure CTS) of the material prepared using only 100% pure chitosan was relatively smooth, and as the content of zero gel increased, the surface roughness was increased. In addition, it can be seen from the photographs of FIG. 2 that the zero gel chitosan hybrid composite of the present invention has a very uniform shape as a whole.

1-2. Microstructure

Figure 3 is a photograph showing the microstructure of the silica zero gel chitosan hybrid composite observed through a transmission electron microscope (TEM).

The twig-shaped black material shown in the photograph represents silica zero gel formed in the organic material through a solgel reaction during the formation of the silica zero gel chitosan compound, and shows a representative fractal structure of the silica silicate structure.

1-3. Biometrics evaluation

FIG. 4 is an image observed through a scanning electron microscope (SEM), arranged over time, photographs obtained through experiments on the formation of mineral components, which are generally performed to evaluate the biocharacteristic of a biomaterial.

When the material was soaked in an analogous biological solution (SBF) and observed for 14 days, the complex of zero-gel chitosan of the present invention was found to be 1 in comparison with 100% pure chitosan, which did not form a trace mineral component for 14 days. Mineral components began to precipitate on the surface, and after 14 days, the surface was completely covered with the mineral component. This is interpreted to be very good biocompatibility of the silica zero gel chitosan complex when compared to the control 100% pure chitosan.

In addition, the degree of infiltration of mineral components in the zero gel chitosan hybrid composite of the present invention was different depending on the composition ratio and components (containing calcium and phosphorus) of the zero gel. In other words, the higher the content of the zero gel, the faster the formation of minerals in the case of the composite using a gel and zero gel containing phosphorus.

Experimental Example  2. Toxicity and Biocompatibility Assessment

Similar bioassay is an experiment to evaluate the toxicity and biocompatibility of a material by evaluating the biocharacteristic of the material. Figures 5 and 6 are the results obtained through in vivo experiments using cells before differentiation occurs.

2-1. Toxicity and Cellular Reactivity

FIG. 5 shows the cell attachment experiments. The cell attachment was confirmed through a confocal laser scanning microscope (CLSM). The cell adhesion experiment is an experiment in which the cells are dispensed on the material and after several hours, the morphology of the cells is simply used to confirm the toxicity of the material and the initial cell reactivity.

For reference, the red-looking substance is a cell attached to the specimen, and healthy cells are well spread and grow, and the round shape represents dying cells.

As a result of the experiment, it was confirmed that the cells that appeared red in both the pure chitosan and silica zero gel chitosan complexes were expanded and attached well. However, it was confirmed that the cells incubated on pure chitosan could not be activated and die round. 5 shows that the silica zero gel chitosan hybrid complex has significantly superior affinity with cells than pure chitosan.

2-2. Biocompatibility

FIG. 6 is a graph measuring the differentiation capacity of cells cultured on silica zero gel chitosan complexes according to the present invention, and comparing the biocompatibility between materials by analyzing the activity of alkaline enzymes.

As a result, the activity of alkaline enzyme of silica zero gel chitosan complex was different depending on the composition ratio and component (containing calcium and phosphorus) of zero gel. That is, the differentiation ability was measured when the hybrid complex was formed using zero gel and chitosan than when using pure chitosan, and in particular, the higher the content of zero gel, the higher the biocompatibility. Furthermore, the differentiation capacity of the hybrid composite was significantly higher than that of the zero gel containing calcium and phosphorus.

As such, it has been demonstrated that the silica zero gel chitosan hybrid composite of the present invention has excellent biocompatibility and can be used in the field of hard tissue.

1 is a process diagram schematically showing a manufacturing process of a silica gel zero gel chitosan organic-inorganic composite for biomedical use in accordance with an embodiment of the present invention.

Figure 2 is a photograph of the surface of the silica zero gel chitosan complex of the present invention and pure chitosan as a control group by scanning electron microscope (SEM).

Figure 3 is a view showing the microstructure of the nano-size silica zero gel chitosan complex observed through a transmission electron microscope (TEM).

FIG. 4 is a photograph showing a process of immersing silica zero gel chitosan hybrid composite of Example 5 and chitosan as a control in a body simulated fluid (SBF) for 14 days and depositing a mineral component.

5 is a photograph showing the results of cell adhesion experiments observed using confocal laser scanning microscope.

6 is a graph showing the results of evaluating the cell differentiation ability (Alkaline Phosphptase activity) of the chitosan silica gel control group and the silica gel gel gel composite of the present invention.

Claims (16)

delete delete delete delete delete delete (a) silica-based zero gel (silica xerogel), (b) an organic / inorganic hybrid complex to which bioactive organics are bound, The physiologically active organic material is uniformly distributed on the surface of the zero gel or three-dimensional networked pores in the zero gel, The organic / inorganic hybrid complex is an organic / inorganic hybrid composite for biomedical use. (a) silica-based zero gel (silica xerogel), (b) an organic / inorganic hybrid complex to which bioactive organics are bound, The physiologically active organic material is uniformly distributed on the surface of the zero gel or three-dimensional networked pores in the zero gel, The organic / inorganic hybrid composite is applied in the form of a membrane (membrane) or bulk (bulk). (a) silica-based zero gel (silica xerogel), (b) an organic / inorganic hybrid complex to which bioactive organics are bound, A shielding film comprising an organic / inorganic hybrid composite in which the physiologically active organic material is uniformly distributed on the surface of the zero gel or three-dimensionally networked pores in the zero gel. (a) silica-based zero gel (silica xerogel), (b) an organic / inorganic hybrid complex to which bioactive organics are bound, Hard tissue regeneration, implantation or replacement material comprising an organic / inorganic hybrid complex is distributed evenly on the surface of the zero gel or three-dimensional networked pores in the zero gel. (a) an organic / inorganic hybrid composite in which a silica-based zero gel (silica xerogel) is combined with a physiologically active organic substance, wherein the physiologically active organic substance is formed on a surface of the zero gel or three-dimensional networked pores in the zero gel. Organic / inorganic hybrid composite uniformly distributed in phase, and (b) a carrier for drug delivery comprising a pharmacological substance that can be encapsulated in the complex. (a) mixing and stirring the silicate, the catalyst, and the distilled water to prepare a silica zero gel appetizer; (b) mixing the physiologically active organic matter in a liquid state to the silica zero gel appetizer prepared in step (a) to form a hybrid material; And (c) neutralizing and drying a liquid hybrid material to prepare an organic / inorganic hybrid composite. The method of claim 12, The silica zero gel applicator of step (a) further comprises a calcium (Ca) -containing precursor compound, a phosphorus (P) -containing precursor compound or both. The method of claim 13, The silica zero gel applicator of step a) includes 80-100 parts by weight of silicate, 0-15 parts by weight of calcium-containing precursor compound and 0-5 parts by weight of phosphorus-containing precursor compound, based on 100 parts by weight of the total. The manufacturing method. The method of claim 12, The bioactive organic material is chitosan, gelatin (gelatine), collagen (collagen), starch (starch), polylactide (PLA), polyglycolide (PGA), polycaprolactone (PCL), poly (caprolactone lactide) Random copolymer (PCLA), poly (caprolactoneglycolide) random copolymer (PCGA), poly (lactideglycolide) random copolymer (PLGA), polyethyloxide (PEO) and polyethylglycol ( PEG) is selected from the group consisting of. The method of claim 12, The manufacturing method is a room temperature solgel (solgel) method.

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