JP2006306786A - Magnetic gel particle, method for producing the same and drug delivery using the same magnetic gel particle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide magnetic gel particles which are gel particles producible under mild conditions, resultantly preventing even deterioration of a physiologically active substance, aggregating and localizing the gel particles in a diseased site by magnetic force applied from the outside of a body or a device inserted into the body and efficiently treating affected parts. <P>SOLUTION: The method for production is carried out as follows. (A) An aqueous solution containing an iron(II) salt, (B) an aqueous solution containing a basic substance and (C) an aqueous solution containing ascorbic acid are suspended and mixed into a lipophilic liquid. (D) A polymer modified with a xanthene dye and (E) an aqueous solution containing the physiologically active substance are suspended and mixed with the resultant suspension. Dispersed particles are then photo-cross-linked by irradiating the mixture liquid with visible light to produce the magnetic gel particles. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a magnetic gel particle that can be used for a drug delivery system (DDS) or the like that can be gathered to a diseased site by magnetic force, a production method thereof, and a drug delivery using the magnetic gel particle.

  Orally administered DDS using a pH-responsive capsule or a capsule that dissolves over time has been performed for a long time, but in recent years, it does not inactivate physiologically active substances and does not damage cells. It has been investigated to embed and encapsulate gel particles with a diameter of several nanometers to several hundreds of nanometers directly into blood by intravenous injection or percutaneous transluminal technique and use them for DDS.

Non-patent documents 1 and 2 below are available as methods for producing such gel particles. In Non-Patent Documents 1 and 2, gel particles are obtained by irradiating gelatin or polyethylene glycol modified with benzophenone with ultraviolet rays to crosslink and insolubilize them. Benzophenone is used as an initiator for radical polymerization by utilizing this reaction because it generates radicals in the molecule by a proton abstraction reaction when irradiated with ultraviolet light.
S. Nishi et al, b-FGF Impregnated Hydrogel Micropheres, ASAIO J, 405-410, 1998 Yasuhide Nakayama, photo-curing hydrophilic polymer, artificial organ 28, 250-255, 1999

  The gel particles described in Non-Patent Documents 1 and 2 are those in which a bioactive substance is supported on gel particles having a gelatin skeleton excellent in biocompatibility, and thus may be administered into blood vessels. However, it has been questioned whether administration of such gel particles into blood vessels is superior to administration of a physiologically active substance alone.

The reason is as follows.
That is, since the crosslinking reaction is performed using ultraviolet rays, part or all of the supported physiologically active substance may be inactivated. As a further big problem, when such gel particles are administered into blood vessels, foreign bodies are actively taken up in organs with many phagocytic cells such as the liver, spleen, lungs and kidneys. Although gel particles are taken in and physiologically active substances are released as a result, the effect of DDS can be expected to some extent, but these gel particles are not taken up by cardiomyocytes, nerve cells, vascular endothelium, capillaries and the like. Therefore, the release of physiologically active substances from gel particles must depend on the diffusion phenomenon due to the concentration gradient, but the release time of physiologically active substances is short because of the short time for localization of gel particles due to blood flow in blood vessels. If the speed is not extremely high, it is difficult to use for DDS.

  The present invention is a method for producing gel particles that can be produced under mild conditions, and thus prevents alteration of a physiologically active substance, and is applied to a disease site by a magnetic force applied from outside the body or from a device inserted into the body. An object of the present invention is to provide a magnetic gel particle capable of efficiently treating an affected area by collecting and localizing gel particles, a magnetic gel particle produced by this method, and a drug delivery including the magnetic gel particle. And

The method for producing gel particles of the present invention (Claim 1)
(A) an aqueous solution containing iron salt (II) (hereinafter sometimes referred to as “component (A)”);
(B) an aqueous solution containing a basic substance (hereinafter sometimes referred to as “component (B)”);
(C) An aqueous solution containing ascorbic acid (hereinafter sometimes referred to as “component (C)”) is suspended and mixed in a lipophilic liquid, and then this suspension is mixed with
(D) A polymer compound modified with a xanthene dye (hereinafter sometimes referred to as “component (D)”) and (E) a physiologically active substance (hereinafter sometimes referred to as “component (E)”). An aqueous solution containing (D) an aqueous solution containing a polymer compound modified with a xanthene dye and an aqueous solution containing (E) a physiologically active substance, and then irradiating the suspension with visible light, Gel particles are obtained by photocrosslinking a polymer compound contained in dispersed particles in a suspension.

  The method for producing magnetic gel particles according to claim 2 is characterized in that, in claim 1, the iron salt (II) is iron (II) halide.

  The method for producing magnetic gel particles according to claim 3 is the method according to claim 1 or 2, wherein the basic substance is selected from the group consisting of an amino group, an N-alkylamino group, and an N, N-dialkylamino group. It is a compound having two or more kinds.

  The method for producing magnetic gel particles according to claim 4 is the method according to any one of claims 1 to 3, wherein the polymer compound is collagen, fibronectin, gelatin, hyaluronic acid, keratanic acid, chondroitin, chondroitin sulfate, elastin, heparan. Sulfuric acid, laminin, thrombospondin, vitronectin, osteonectin, entactin, casein, polyethylene glycol, polypropylene glycol, polyglycidol, polyglycidol side chain esterified product, polylactic acid, polyglycolic acid, cyclic ester polymer, polyvinyl alcohol Copolymers of hydroxyethyl methacrylate and dimethylaminoethyl methacrylate, copolymers of hydroxyethyl methacrylate and methacrylic acid, alginic acid, polyacrylamide, polydimethyla Characterized in that the Riruamido the group consisting of polyvinyl pyrrolidone is at least one selected.

  The method for producing magnetic gel particles according to claim 5 is the method according to any one of claims 1 to 4, wherein the physiologically active substance is heparin, low molecular weight heparin, hirudin, argatroban, formacholine, bapiprost, prostamorin, prostamorin. Homologues, dextran, lofeproargol chloromethyl ketone, dipyridamole, platelet protein receptor antibody of glycoprotein, recombinant hirudin, thrombin inhibitor, vascular peptin, vascular tensin converting enzyme inhibitor, steroid, fibroblast growth Factor antagonist, fish oil, omega-3 fatty acid, histamine, antagonist, HMG-CoA reductase inhibitor, ceramine, serotonin blocking antibody, thioprotease inhibitor, trimazol pyridimine, interferon, rapamycin, F 506, platelet-derived growth factor, epidermal growth factor, transforming growth factor α, insulin-like growth factor, insulin-like growth factor binding protein, hepatocyte growth factor, vascular endothelial growth factor, angiopoietin, nerve growth factor, brain-derived nerve Trophic factor, ciliary neurotrophic factor, transforming growth factor β, latent transforming growth factor β, activin, osteoplasmic protein, fibroblast growth factor, tumor growth factor β, diploid fibroblast growth factor, Heparin-binding epidermal growth factor-like growth factor, schwanoma-derived growth factor, amphiregulin, betacellulin, epigrelin, lymphotoxin, erythroepoetin, tumor necrosis factor α, interleukin-1β, interleukin-6, interleukin-8 , Interleukin-17, interferon, antiviral agent, antibacterial agent, antibiotic, anti Cancer, antagonist, immunosuppressant, receptor blocker, antiparkinsonian, vitamin, flavonoid, antiarrhythmic, insulin, calcitonin, radioactive substance, reduced glutathione, nitroglycerin, prostaglandin, polyphenol, erythropoietin , RNA, DNA, and at least one selected from the group consisting of RNA and / or DNA-introduced vectors.

  The method for producing magnetic gel particles according to claim 6 is characterized in that, in any one of claims 1 to 5, the xanthene dye is eosin.

  The method for producing magnetic gel particles according to claim 7 is the method according to any one of claims 1 to 6, wherein the lipophilic liquid is selected from the group consisting of hydrocarbons, halogenated hydrocarbons, and natural oils. It is characterized by more than seeds.

  The method for producing magnetic gel particles according to claim 8 is characterized in that, in any one of claims 4 to 7, the polymer compound is gelatin.

  The method for producing magnetic gel particles according to claim 9 is the method according to claim 8, wherein the polymer compound modified with xanthene dye introduces 1 to 10 xanthene dye molecules in one gelatin molecule. It is characterized by.

  The method for producing magnetic gel particles according to claim 10 is the method according to claim 9, wherein the polymer compound modified with a xanthene dye introduces 2 to 6 xanthene dye molecules in one gelatin molecule. It is characterized by.

  The method for producing magnetic gel particles according to claim 11 is characterized in that, in any one of claims 1 to 10, the diameter of the produced gel particles is 2 nm to 200 μm.

  The magnetic gel particles of the present invention (Claim 12) are produced by such a method for producing magnetic gel particles of the present invention.

  The drug delivery of the present invention (Claim 13) is characterized by including such magnetic gel particles of the present invention.

  In the method for producing gel particles of the present invention, for example, after the iron salt (II) of (A) is dispersed in an aqueous phase in a lipophilic liquid, the basic substance of (B) is suspended and mixed. As a result, the iron salt (II) becomes iron hydroxide (II), which is further oxidized by the radical oxygen generated by the decomposition of ascorbic acid (C) using iron hydroxide (II) as a catalyst. It becomes some iron trioxide particles. This oxidation reaction has an effect that the particle diameters of the nano-sized triiron tetroxide particles produced are uniform because the reaction proceeds quantitatively.

  Further, the produced triiron tetroxide particles are formed by xanthene dyes in which ascorbic acid present on the surface of the particles when coated with the polymer compound (D) in a lipophilic liquid is present in the polymer compound. It is insolubilized so as to embed triiron tetroxide particles by acting as a radical counter necessary for the crosslinking reaction, so-called hydrogen toner. This photocrosslinking reaction using ascorbic acid as a hydrogen toner is cross-linked by light in the visible region, so that even a physiologically active substance that is weak against energy load such as heat and light is not deactivated. Magnetic gel particles contained in the gel layer can be obtained.

  The magnetic gel particles of the present invention thus obtained can efficiently treat the affected part by collecting the gel particles at the diseased site by magnetic force after intravascular administration in DDS therapy.

Hereinafter, embodiments of the present invention will be described in detail.
Although there is no restriction | limiting in particular as divalent iron salt of the aqueous solution containing (A) iron salt (II) used by this invention, Iron halides (II), such as iron chloride and iron bromide, are used suitably. be able to. These iron salts may be used alone or in combination of two or more.

  (A) The concentration of the iron salt (II) in the aqueous solution containing the iron salt (II) is preferably in the range of 0.01 to 1 mol / liter. When this concentration is lower than 0.01 mol / liter, the magnetic properties of the gel particles obtained are low, and when it is higher than 1 mol / liter, the particle size of the gel particles is increased.

  (B) As the basic substance of the aqueous solution containing the basic substance, any substance can be used as long as the pH of the system can be made neutral to alkaline in order to produce iron hydroxide from iron salt (II). In general, alkali metal hydroxides and amines of inorganic compounds can be used, but the crosslinking reaction of xanthene dyes is supported by assisting the properties as a hydrogen donor in the photocrosslinking reaction of (C) ascorbic acid described later. In view of the acceleration effect, basic substances include compounds having an amino group, N-alkylamino group, N, N-dialkylamino group, such as ammonia, ethylamine, dimethylamine, sodium dimethylaminobenzoate, 2 -Dimethylaminoethanol, N-methyl-2-pyrrolidinone, sodium dimethylaminopropyl acetate, N, N-dimethylformami N, N-dimethylacrylamide oligomer, 1,1,4,7,10,10-hexamethyltriethylenetetramine, 2- (dimethylamino) ethyl acrylate oligomer, N- (3-dimethylaminopropyl) acrylamide oligomer, etc. Is preferably used. These basic substances may be used alone or in combination of two or more.

  (B) As a basic substance concentration in an aqueous solution containing a basic substance, if it is excessively high, (C) ascorbic acid, (D) a xanthene dye-modified polymer compound and (E) May cause condensation, decomposition, denaturation, and deactivation of the physiologically active substance, and if it is too low, it will be difficult to form iron hydroxide from the iron salt (II), resulting in a magnetic substance. Since it becomes impossible to form ferric tetroxide, it is preferably about 0.01 to 10.0 mol / L. By performing in such a concentration range, the generation rate of radicals due to the decomposition of ascorbic acid and the ternary tetroxide are improved. It becomes possible to harmonize the production rate of iron.

  (C) Ascorbic acid generates radical oxygen upon contact with iron hydroxide to oxidize iron hydroxide to triiron tetroxide, and simultaneously coats the triiron tetroxide particles as described below ( D) It acts as a hydrogen donor when a layer of a polymer compound modified with a xanthene dye as a component is formed by photocrosslinking and insolubilization. That is, it acts as a hydrogen donor that is a radical counter in the crosslinking reaction of the xanthene dye by light irradiation.

  Of course, in addition to ascorbic acid, cysteines, thiols, alcohols, reducing sugars, polyphenols and the like can be added as hydrogen donors to accelerate the crosslinking reaction, but this is not an essential component.

  (C) Ascorbic acid concentration in the aqueous solution containing ascorbic acid is excessively high, the oxidation rate of iron (II) hydroxide increases, and the growth of secondary particles of fine particles generated by the oxidation reaction is promoted. Therefore, as a result, there is a possibility that the particle diameter of the triiron tetraoxide particles becomes large or non-uniform. On the other hand, if the concentration is too low, the solution may shift to the acidic side, and iron hydroxide (II) may not be efficiently generated, or the amount of generated radical oxygen may be insufficient. It is preferably about 1 to 10.0 mol / L.

  The polymer compound modified with the xanthene dye (D) is used as a substance that gels by generating radicals upon irradiation with visible light. Specific examples of polymer compounds modified with xanthene dyes include collagen, fibronectin, gelatin, hyaluronic acid, keratanic acid, chondroitin, chondroitin sulfate, elastin, heparan sulfate, laminin, thrombospondin, Vitronectin, osteonectin, entactin, gazein, polyethylene glycol, polypropylene glycol, polyglycidol, polyglycidol side chain esterified product, polylactic acid, polyglycolic acid, cyclic ester polymer, polyvinyl alcohol hydroxyethyl methacrylate and dimethylaminoethyl methacrylate Copolymer, hydroxyethyl methacrylate and methacrylic acid copolymer, alginic acid, polyacrylamide, polydimethylacrylamide, poly vinyl Rupiroridon, and the like. Moreover, as a polymer of cyclic ester here, it is compoundable by carrying out ring-opening polymerization of a C2-C14 cyclic ester compound. Examples of such cyclic ester compounds include butyrolactone, valerolactone, caprolactone, caprylolactone, laurolactone, valmilactone, stearolactone, glycoside, lactide, coumarin, crotolactone, α-angelica lactone and β-angelica lactone, Examples include 1,4-dioxane-2-one, 1,5-dioxepan-2-one, and trimethylene carbonate.

  (D) The polymer compound modified with a xanthene dye may be used alone or in combination of two or more.

  Eosin is suitable as the xanthene dye in the polymer compound modified with (D) xanthene dye, and eosinized gelatin is suitable as the polymer compound modified with (D) xanthene dye. This eosinized gelatin will be described later. When gelatin is modified with a xanthene dye, the number of xanthene dye molecules introduced per molecule of gelatin is preferably 10 or less, and particularly preferably 2 to 6. When this introduction number is more than 10, gelatin becomes hardly soluble in water, and eventually the gel particles become hard.

  (E) Examples of physiologically active substances include heparin, low molecular weight heparin, hirudin, argatroban, formacholine, bapiprost, prostamorin, prostaquilin homologue, dextran, lofepro-algchloromethyl ketone, dipyridamole, glycoprotein platelet membrane receptor Antibody, recombinant hirudin, thrombin inhibitor, vascular peptin, vascular tensin converting enzyme inhibitor, steroid, fibroblast growth factor antagonist, fish oil, omega-3 fatty acid, histamine, antagonist, HMG-CoA reductase inhibitor , Seramine, serotonin blocking antibody, thioprotein inhibitor, trimazole pyridimine, interferon, rapamycin, FK506, platelet-derived growth factor, epidermal growth factor, transforming growth factor α, in Phosphorus-like growth factor, insulin-like growth factor binding protein, hepatocyte growth factor, vascular endothelial growth factor, angiopoietin, nerve growth factor, brain-derived neurotrophic factor, ciliary neurotrophic factor, transforming growth factor β, latency Type transforming growth factor β, activin, osteoplasmic protein, fibroblast growth factor, tumor growth factor β, diploid fibroblast growth factor, heparin-binding epidermal growth factor-like growth factor, schwanoma-derived growth factor, amphire Glin, betacellulin, epigrelin, lymphotoxin, erythroepoetin, tumor necrosis factor α, interleukin-1β, interleukin-6, interleukin-8, interleukin-17, interferon, antiviral agent, antibacterial agent, antibiotic , Antagonists, immunosuppressants, receptor blockers, antiparkinsonian drugs, vitamin drugs, Rabonoido, antiarrhythmic agents, insulin, calcitonin, radioactive substances, reduced glutathione, nitroglycerin, prostaglandins, polyphenols, mention may be made of erythropoietin, RNA, DNA, and the vector was introduced RNA and / or DNA. These physiologically active substances may be used alone or in combination of two or more.

  A polymer modified with a xanthene dye in an aqueous solution containing (D) a xanthene dye-modified polymer compound and (E) a physiologically active substance, or (D) a xanthene dye-modified polymer compound When the compound concentration is excessively high, the density of the layer embedding the ferric tetroxide particles increases, and as a result, (E) the amount of the physiologically active substance supported is reduced, and the concentration is excessively low. If there is, (E) a layer supporting a physiologically active substance is not formed or the particles of triiron tetroxide cannot be completely embedded, and therefore it is preferably about 0.1 to 50% by weight. In addition, the concentration of the physiologically active substance in the aqueous solution containing (D) the xanthene dye-modified polymer compound and (E) the physiologically active substance, or (E) the physiologically active substance is the concentration of the physiologically active substance used. Effective dose number and concentration at risk of toxicity, type of polymer compound modified with (D) xanthene dye that embeds triiron tetroxide particles, density and thickness of the formed layer, Although it is appropriately set by those skilled in the art in consideration of a target sustained release rate and the like, for example, a layer of about 100 μm is formed using a polyethylene glycol polymer compound (molecular weight of about 2000), and bFGF is 48 If it is desired to release slowly over a period of time, typically, it is preferably about 0.5 to 50.0 μg / mL.

  (A) an aqueous solution containing the iron salt (II) in a lipophilic liquid, (B) an aqueous solution containing a basic substance, (C) an aqueous solution containing ascorbic acid, (D) a polymer compound modified with a xanthene dye, and When (E) an aqueous solution containing a physiologically active substance (or (D) an aqueous solution containing a polymer compound modified with a xanthene dye and (E) an aqueous solution containing a physiologically active substance) is added, these use a capillary or the like. Add and mix as droplets, or suspend and disperse using a stirrer such as a defoaming stirrer, and add or remove the aqueous solution by dropping, etc. It is preferable to make it. By performing these reactions in a suspended state in a lipophilic liquid, the particle size distribution of the finally produced magnetic gel particles can be made narrow and monodispersed. In this case, it is preferable to disperse the obtained gel particles so that the diameter thereof is 2 nm to 200 μm, particularly 10 nm to 100 μm.

  In addition, although the polymer compound modified with the xanthene dye of (D) is also set as an aqueous solution, this may be dissolved in the aqueous solution together with (E) the physiologically active substance, and is set as a different aqueous solution. The aqueous physiologically active substance may be added separately to the lipophilic liquid.

  (D) An aqueous solution containing a polymer compound modified with a xanthene dye and (E) a physiologically active substance (or (D) an aqueous solution containing a polymer compound modified with a xanthene dye and (E) an aqueous solution containing a physiologically active substance) Is added after suspending and mixing the lipophilic liquid with the aqueous solution containing (A) the iron salt (II), (B) the aqueous solution containing the basic substance, and (C) the aqueous solution containing ascorbic acid. The order of addition of (A) the aqueous solution containing the iron salt (II), (B) the aqueous solution containing the basic substance, and (C) the aqueous solution containing ascorbic acid to the lipophilic liquid is not particularly limited. (B) an aqueous solution containing a basic substance, (A) an aqueous solution containing an iron salt (II), (C) an aqueous solution containing ascorbic acid, A) Aqueous solution containing iron salt (II), (C) A An aqueous solution containing corbic acid, (B) an aqueous solution containing a basic substance, (A) an aqueous solution containing an iron salt (II), (B) an aqueous solution containing a basic substance, (C) ascorbine You may add in order of the aqueous solution containing an acid.

  As the lipophilic liquid, hydrocarbons such as hexane, cyclohexane and liquid paraffin; halogenated hydrocarbons such as chloroform and methylene chloride; natural oils such as castor oil and olive oil; and the like, these lipophilic liquids can be used. One kind may be used alone, or two or more kinds may be mixed and used.

  One or more surfactants such as polyoxyethylene ceyl ether, oxyethylene oxypropylene copolymer and sodium dodecyl sulfate may be added to this lipophilic liquid, whereby the particles can be dispersed more finely. . The amount of the surfactant added to the lipophilic liquid is preferably about 0.1 to 50% by weight.

  Further, a thickener such as polyethylene glycol may be added to the lipophilic liquid, whereby the dispersed particle size can be made uniform or the dispersed particle size can be reduced. The addition amount of the thickener to the lipophilic liquid is preferably about 0.1 to 20% by weight.

(A) an aqueous solution containing an iron salt (II) in a lipophilic liquid, (B) an aqueous solution containing a basic substance, (C) an aqueous solution containing ascorbic acid, and (D) a polymer compound modified with a xanthene dye and ( E) Light irradiation after adding and suspending an aqueous solution containing a physiologically active substance ((D) an aqueous solution containing a polymer compound modified with a xanthene-based dye and (E) an aqueous solution containing a physiologically active substance) has a wavelength of 400 It is preferable to adjust the visible light of ˜700 nm to 1 to 500 mW / cm ² and irradiate it for about 1 to 60 minutes.

  Thus, the magnetic gel particles of the present invention obtained by gelling the dispersed particles by photocrosslinking preferably have a diameter of 2 nm to 200 μm, particularly 10 nm to 100 μm. If the diameter of the magnetic gel particles is less than 2 nm, the amount capable of supporting the (C) physiologically active substance is small and the mobility to the magnetic force is lost, and if it exceeds 200 μm, the risk of vascular occlusion increases.

  Such magnetic gel particles swell about 1 to 30 times when suspended in physiological saline.

  Moreover, it is preferable that the content rate of the ferric tetroxide contained in this magnetic gel particle is 20 to 98 weight%. If this ratio is too large, (C) it becomes impossible to carry a physiologically active substance, and if it is too small, the function of guiding to the affected area with a magnetic force is impaired.

  Such a magnetic gel particle of the present invention is effectively administered by a physiologically active substance carried by the gel particle by assembling the gel particle to a diseased site by magnetic force after intravascular administration in DDS therapy as a drug delivery. Can be treated.

  In this case, as a method for applying the magnetic force, there are a method in which the magnetic force is directly applied from the body surface on the affected part, and a method in which the magnetic force is applied from a device inserted into the body. Such devices include those that are percutaneously inserted into the tissue near the affected area, vascular catheters that can apply a magnetic force in the vicinity of the affected area, and those that are placed in blood vessels such as stent grafts. However, this is not the case.

  When the magnetic gel particle of the present invention is used as a drug delivery, the particle size of the magnetic gel particle is less than 400 nm, which is easily recognized as a foreign substance in the blood vessel, causing a risk of blockage of a capillary vessel, and the direction of the mini magnet. For example, the thickness is preferably 2 to 200 nm in consideration of carrying a physiologically active substance having an effective dose number because the properties are unified and gathered by magnetic force.

Next, eosinized gelatin suitable for use in the present invention will be described.
Here, the gelatin may be a normal gelatin having a molecular weight of 5,000 to 100,000 and an amino group of about 10 to 100 per molecule.
Eosinized gelatin is prepared by introducing eosin into the side chain of gelatin according to the following reaction.

  The number of eosin introduced into the gelatin molecule can be calculated based on, for example, the absorbance of an aqueous solution of eosinized gelatin measured at the maximum absorption wavelength of eosin at 522 nm and the molar extinction coefficient of eosin (ε = 94755). The number is preferably 1 to 10, more preferably about 2 to 5, with respect to the molecule. If the number of compounds having a photosensitive group such as eosin is small, the gelation rate is lowered, and if it is more than necessary, the flexibility inherent to gelatin may be impaired, and it becomes hardly soluble in water. End up.

  This eosinized gelatin is a viscous liquid. For example, when an aqueous solution having a concentration of 1 to 10% by weight is used, visible light of about 300 to 30,000 lx, particularly for use with a living body, with a relatively low illuminance of about 300 to 15,000 lx, Can be cured in a gel state by irradiating visible light having a low influence for about 0.1 to 30 minutes.

  Hereinafter, the present invention will be described more specifically with reference to synthesis examples and examples.

Synthesis Example 1: Preparation of iron salt (II) aqueous solution and ascorbic acid aqueous solution Purified water obtained by sufficiently deoxidizing iron chloride (II) tetrahydrate (manufactured by Kanto Chemical Co., Ltd., JIS special grade reagent) by nitrogen bubbling for 24 hours ( A 0.3M solution was prepared by dissolving in JP Water for Injection.

  Similarly, ascorbic acid (manufactured by Kanto Chemical Co., Ltd., special grade reagent) was dissolved in purified water deoxygenated to prepare a 0.3 M solution.

Synthesis Example 2: Synthesis of Eosinized Gelatin N-ethyl-N ′-(3-dimethylaminopropyl) carbodiimide (WSC), which is a water-soluble carbodiimide, is added to gelatin (molecular weight 95,000, amino group content approximately 37 / molecule). In the presence of, eosin was synthesized by linking eosin to the amino group of the side chain of gelatin by the following reaction to introduce about 5 eosin per molecule of gelatin. Purification was performed by dialysis, and the rate of introduction of eosin into the gelatin chain was calculated from the absorbance at 522 nm.

Synthesis Example 3 Preparation of Solution Containing Polymer and Bioactive Substance Modified with Xanthene Dye The eosinized gelatin synthesized in Synthesis Example 2 was dissolved in water to a concentration of 11% by weight. As physiologically active substances, heparin and fibroblast growth factor (FGF-2) were dissolved in water. The eosinized gelatin and a physiologically active substance solution were mixed to obtain an aqueous solution containing 10% by weight of a polymer compound modified with a xanthene dye and 2 μg / mL of the physiologically active substance.

Example 1
[Production of magnetic gel particles for DDS]
While stirring 1.0 L of a 0.25M polyoxyethylene (20) cetyl ether (Brij58) cyclohexane solution with a homogenizer (Hoki Disper F, manufactured by Tokushu Kika Kogyo Co., Ltd.), 5.0 mL of a 0.3 M iron (II) chloride solution Were mixed dropwise. These operations were performed in a closed system under nitrogen flow. Subsequently, 5.0 mL of 0.3 M ascorbic acid solution was dropped and mixed and sufficiently emulsified and dispersed, and then aqueous ammonia was added dropwise to adjust the pH of the aqueous phase emulsified and dispersed to about 9.0. Stirring was continued for 1 hour, and 50 mL of the solution containing the polymer compound and physiologically active substance prepared in Synthesis Example 3 was added dropwise using a capillary. Thereafter, visible light having a wavelength of 400 nm to 520 nm was adjusted to 200 mW / cm ² with a halogen lamp (manufactured by Ushio Electric) in a photochemical reaction apparatus (manufactured by Ushio Electric) and irradiated for 20 minutes to crosslink eosinized gelatin.

  This was cooled in a 4 ° C. water bath, the precipitate was collected by filtration, washed with cyclohexane, and the remaining cyclohexane was evaporated in a desiccator to obtain gel particles for drug delivery system having an average particle size of about 1 μm ( (See FIG. 1).

  When this gel particle was suspended in physiological saline, it swollen and the average particle size became about 10 μm (see FIG. 2).

  Further, when the gel particles were treated in a muffle furnace at 600 ° C., the surface gel layer was burned off, and confirmed by TEM, a cuboid crystal of about 10 to 60 nanometers of triiron tetroxide particles was observed. (See FIG. 3).

  The content of triiron tetroxide in the gel particles was about 90% by weight based on the dry gel particles.

[Evaluation of sustained release of bioactive substances]
The magnetic gel particles for DDS thus obtained were suspended in the DMEM medium, and the fibroblast growth factor (FGF-2) released into the medium over time was measured by the ELISA method.

  Gel particles in aliquots collected over time were allowed to act on an aqueous solution of toluidine blue dye, and the elution continuity of heparin was confirmed based on whether or not the beads were colored. About 90% of fibroblast growth factor (FGF-2) was released in 19 hours. Although heparin was colored for up to 2 hours, the gel particles were not colored thereafter, and it was confirmed that almost the entire amount was released in 2 hours.

  When the DMEM medium was stirred with a magnetic stirrer and a permanent magnet was placed on the container wall, the gel particles gathered on the container wall and became visible without diffusing in the flow of the medium. When the magnet was moved away, the gel particles diffused and dispersed into the medium.

2 is a photomicrograph of magnetic gel particles produced in Example 1. It is a microscope picture when the magnetic gel particle manufactured in Example 1 is suspended in physiological saline. It is a TEM photograph of the magnetite particle which remained after baking the magnetic gel particle manufactured in Example 1 at 600 degreeC.

Claims (13)

(A) an aqueous solution containing iron salt (II);
(B) an aqueous solution containing a basic substance;
(C) Suspending and mixing an aqueous solution containing ascorbic acid into a lipophilic liquid,
(D) an aqueous solution containing a polymer compound modified with a xanthene dye and (E) a physiologically active substance, or (D) an aqueous solution containing a polymer compound modified with a xanthene dye and (E) an aqueous solution containing a physiologically active substance. Magnetic gel particles characterized in that gel particles are obtained by suspending and mixing, and then irradiating the suspension with visible light to photocrosslink the polymer compound contained in the dispersed particles in the suspension. Manufacturing method.   The method for producing magnetic gel particles according to claim 1, wherein the iron salt (II) is iron (II) halide.   The magnetic gel particle according to claim 1 or 2, wherein the basic substance is a compound having one or more selected from the group consisting of an amino group, an N-alkylamino group, and an N, N-dialkylamino group. Manufacturing method.   The polymer compound is collagen, fibronectin, gelatin, hyaluronic acid, keratanic acid, chondroitin, chondroitin sulfate, elastin, heparan sulfate, laminin, thrombospondin, vitronectin, osteonectin, enteractin, gazein, polyethylene glycol, polypropylene glycol, poly Glycidol, polyglycidol side chain esterified product, polylactic acid, polyglycolic acid, cyclic ester polymer, polyvinyl alcohol hydroxyethyl methacrylate and dimethylaminoethyl methacrylate copolymer, hydroxyethyl methacrylate and methacrylic acid copolymer, At least one selected from the group consisting of alginic acid, polyacrylamide, polydimethylacrylamide and polyvinylpyrrolidone Method of manufacturing a magnetic gel particles according to any one of claims 1 to 3 that.   The physiologically active substance is heparin, low molecular weight heparin, hirudin, argatroban, formacholine, bapiprost, prostamorin, prostakyrin homologue, dextran, lofepro-argchloromethyl ketone, dipyridamole, glycoprotein platelet membrane receptor antibody, group Reversible hirudin, thrombin inhibitor, vascular peptin, vascular tensin converting enzyme inhibitor, steroid, fibroblast growth factor antagonist, fish oil, omega-3 fatty acid, histamine, antagonist, HMG-CoA reductase inhibitor, ceramine, Serotonin blocking antibody, thioprotease inhibitor, trimazole pyridimine, interferon, rapamycin, FK506, platelet-derived growth factor, epidermal growth factor, transforming growth factor α, insulin-like Growth factor, insulin-like growth factor binding protein, hepatocyte growth factor, vascular endothelial growth factor, angiopoietin, nerve growth factor, brain-derived neurotrophic factor, ciliary neurotrophic factor, transforming growth factor β, latent trait Conversion growth factor β, activin, osteoplasmic protein, fibroblast growth factor, tumor growth factor β, diploid fibroblast growth factor, heparin-binding epidermal growth factor-like growth factor, schwanoma-derived growth factor, amphiregulin, Betacellulin, epigrelin, lymphotoxin, erythroepoetin, tumor necrosis factor α, interleukin-1β, interleukin-6, interleukin-8, interleukin-17, interferon, antiviral agent, antibacterial agent, antibiotic, antimicrobial Cancer drugs, antagonists, immunosuppressants, receptor blockers, antiparkinsonian drugs, vitamin drugs Selected from the group consisting of flavonoids, antiarrhythmic agents, insulin, calcitonin, radioactive substances, reduced glutathione, nitroglycerin, prostaglandins, polyphenols, erythropoietin, RNA, DNA and RNA and / or DNA-introduced vectors The method for producing magnetic gel particles according to claim 1, wherein the method is at least one kind.   The method for producing magnetic gel particles according to any one of claims 1 to 5, wherein the xanthene dye is eosin.   The method for producing magnetic gel particles according to any one of claims 1 to 6, wherein the lipophilic liquid is one or more selected from the group consisting of hydrocarbons, halogenated hydrocarbons, and natural oils.   The method for producing magnetic gel particles according to claim 4, wherein the polymer compound is gelatin.   The method for producing magnetic gel particles according to claim 8, wherein the polymer compound modified with a xanthene dye is one in which 1 to 10 xanthene dye molecules are introduced into one molecule of gelatin.   The method for producing magnetic gel particles according to claim 9, wherein the polymer compound modified with a xanthene dye is one in which 2 to 6 xanthene dye molecules are introduced into one molecule of gelatin.   The method for producing magnetic gel particles according to any one of claims 1 to 10, wherein the diameter of the produced gel particles is 2 nm to 200 µm.   Magnetic gel particles produced by the method for producing gel particles according to any one of claims 1 to 11.   A drug delivery comprising the magnetic gel particles according to claim 12.

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