JP2009184973A - Sustained release antimicrobial agent preparation using carbon nanohorn as carrier - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sustained release antimicrobial agent preparation containing an antimicrobial agent, the release of which is sustained by using carbon nanohorns as a carrier. <P>SOLUTION: The sustained release antimicrobial agent preparation involves the antimicrobial agent containing an inorganic antimicrobial agent such as silver, a synthetic organic antimicrobial agent, a natural antimicrobial agent or the like, and the antimicrobial agent has the opened carbon nanohorns including at least one kind of a germicidal agent and an antibiotic as the carrier. Chemical modification for controlling the release rate of the involved chemical may be applied to the sidewall, the tip or the edge of the opening part of the carbon nanohorn. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an antibacterial sustained-release preparation using carbon nanohorn as a carrier.

  Moreover, what adsorb | sucked the inorganic type antimicrobial agent to the adsorption agent as a formulation containing an antimicrobial agent is proposed (for example, refer patent document 1). The antibacterial product described in Patent Document 1 is exemplified by carbon such as activated carbon, charcoal, and carbon nanotube, silica gel, and the like as an adsorbent. However, the carbon nanotube has a small diameter of about 1.4 nm, and it is not easy to include an organic antibacterial agent therein.

  Further, Patent Document 2 relates to a product similar to Patent Document 1, but discloses the use of carbon nanohorns as an adsorbent. However, Patent Document 2 does not disclose an adsorbed substance.

  Patent Document 3 discloses that carbon nanohorns contain steroidal hormones such as anticancer agents such as dexomethasone and cisplatin, but are not antibacterial agents.

Japanese Patent Laid-Open No. 2003-40718 JP 2006007217 A JP-A-2005-343885

  First, the necessity of sustained release of the antibacterial agent preparation will be described by taking vancomycin hydrochloride, which is one of the antibiotics, as an example. Vancomycin hydrochloride is widely used as a remedy for methicillin-resistant Staphylococcus aureus (MRSA), which is a serious problem causing bacterial infections. However, it has nephrotoxicity as a side effect, and has an optimal blood concentration and toxicity. Since the expression levels are close to each other, it is necessary to strictly adjust the dose and interval based on the measurement of blood levels.

  Further, as a general property of antibiotics, local administration to a surgical site or infected site has little effect because the drug concentration cannot be maintained and decreases rapidly.

  As a means for solving these drawbacks, a method of sustained release of a drug is known, and a preparation using a microparticulate of poly (lactide-co-glycolide) (PLGA) as a carrier as a sustained release preparation of vancomycin hydrochloride is reported. However, in this preparation, about 90% of vancomycin hydrochloride contained is released within 24 hours, and the optimum concentration cannot be maintained for a long time.

  As described above, in the case of vancomycin hydrochloride, the sustained release preparation technique using a microparticulate of poly (lactide-co-glycolide) (PLGA) requires administration once a day, compared with vancomycin hydrochloride alone administration. There are few benefits.

  In addition, by developing a formulation that allows sustained release over a long period of time, it is possible to maintain the antibacterial action for a long time with a single administration, and there is only one administration opportunity, such as extended administration intervals or local use at the surgical site. This is useful for long-term maintenance of antibacterial effects in situations where there is no such thing.

  Then, the technical subject of this invention is providing the antimicrobial agent sustained release formulation containing the antimicrobial agent with which sustained release was achieved by using carbon nanohorn as a carrier.

  ADVANTAGE OF THE INVENTION According to this invention, the antimicrobial agent sustained release formulation characterized by having as a carrier the carbon nanohorn which included the antimicrobial agent is obtained.

  Further, according to the present invention, in the antibacterial agent sustained-release preparation, the antibacterial agent includes an inorganic antibacterial agent, a synthetic organic antibacterial agent, a natural product antibacterial agent, and the like. A modified preparation is obtained. In the present invention, examples of the inorganic antibacterial agent include silver and silver antibacterial agents, but the present invention is not limited thereto.

  Moreover, according to the present invention, the antibacterial agent sustained release preparation, wherein the antibacterial agent contains at least one of a bactericidal agent and an antibacterial agent.

  Here, in the present invention, examples of the bactericidal agent include iodine, and examples of the antibacterial agent include antibiotics such as vancomycin hydrochloride, but are not limited thereto. .

  Moreover, according to the present invention, in any one of the antibacterial agent sustained-release preparations, an antibacterial agent sustained-release preparation is obtained, wherein the carbon nanohorn is a carbon nanohorn having an opening.

  Further, according to the present invention, in the antibacterial agent sustained-release preparation, the side wall, tip, or opening edge of the carbon nanohorn is chemically modified to control the release rate of the encapsulated drug. Thus, an antibacterial sustained-release preparation is obtained.

  Moreover, according to the present invention, in the antibacterial agent sustained-release preparation, the side wall, the tip, or the opening edge of the carbon nanohorn is chemically modified to increase the hydrophilicity of the carbon nanohorn, which is hydrophobic, or An antibacterial sustained-release preparation characterized by chemical modification for avoiding phagocytosis of the reticuloendothelial system is obtained.

  Further, according to the present invention, in the antibacterial agent sustained-release preparation, it is specifically expressed in the affected part so as to selectively reach the affected part at the side wall, tip, or edge of the opening of the carbon nanohorn. An antibacterial sustained-release preparation characterized in that a molecule that selectively adheres to an antibody or the like is added.

  Further, according to the present invention, there is provided an antibacterial agent sustained-release preparation characterized in that in any one of the antibacterial agent sustained-release preparations, a functional substance is physically adsorbed on the carbon nanohorn or the chemically modified carbon nanohorn. can get.

  Further, according to the present invention, in the antibacterial agent sustained-release preparation, the function of the functional substance is controlled release of the encapsulated antibacterial agent, antibacterial action, drug, hydrophilic molecule, target molecule, etc. Thus, an antibacterial sustained-release preparation is obtained.

  In addition, according to the present invention, there can be obtained an antibacterial agent sustained-release preparation characterized in that the antibacterial agent-encapsulated carbon nanohorn is used for skin disease treatment in any one of the antibacterial agent sustained-release preparations.

  In addition, according to the present invention, an antibacterial agent sustained-release preparation characterized by using the antibacterial agent-encapsulating carbon nanohorn mixed with a substance having a function that facilitates application to the skin or the like can be obtained.

  Further, according to the present invention, in the antibacterial agent sustained-release preparation according to any one of the above, the antibacterial agent-containing carbon nanohorn is used by being administered in the body for the treatment of skin diseases. A release formulation is obtained.

  In addition, according to the present invention, there can be obtained a method for producing a sustained-release preparation of an antibacterial agent characterized in that carbon nanohorns are subjected to pore opening treatment as a carrier and the antibacterial agent is encapsulated.

  According to the present invention, in the method for producing a sustained-release preparation for an antibacterial agent, the antibacterial agent includes an inorganic antibacterial agent, a synthetic organic antibacterial agent, a natural product antibacterial agent, and the like. A method for producing a sustained-release preparation is obtained.

  According to the present invention, in the method for producing an antibacterial agent sustained-release preparation, the antibacterial agent comprises at least one of a bactericidal agent and an antibiotic agent. A method is obtained.

  ADVANTAGE OF THE INVENTION According to this invention, the antimicrobial agent sustained release formulation containing the antimicrobial agent with which sustained release was achieved can be provided by using carbon nanohorn as a carrier.

  The present invention will be described in more detail.

  In the present invention, the carbon nanohorn (CNH) is formed by forming a spherical aggregate having a diameter of 80 to 100 nm in which graphite sheets are rounded in a cylindrical shape and single-walled carbon nanotubes having a conical end shape are arranged almost radially.

  CNH can make a hole in the tube wall, and can control the encapsulation and release of the drug to the tube by controlling the opening and chemical modification, and the usefulness of the drug as a sustained-release preparation carrier has been reported. Has been.

  In the present invention, a superior sustained release preparation of an antibacterial agent such as vancomycin hydrochloride is designed by using CNH as a drug carrier.

  The antimicrobial agent release preparation of the present invention has carbon nanohorns containing an antibacterial agent as a carrier.

  Here, the carbon nanohorn is preferably an apertured carbon nanohorn having an aperture provided by an aperture treatment such as hydrogen peroxide.

  The antibacterial agent may also include an inorganic antibacterial agent, a synthetic organic antibacterial agent, and various natural product antibacterial agents.

Examples of inorganic antibacterial agents include metal ions such as manganese (Mn ²⁺ ), iron (Fe ³⁺ ), cobalt (Co ²⁺ ), nickel (Ni ²⁺ ), and copper (Cu ²⁺ ) in addition to silver and silver antibacterial agents. Compounds such as oxides or hydroxides containing are preferred.

  Synthetic organic antibacterial agents include imidazole derivatives such as 2- (4-thiazolyl) benzimidazole, N-haloalkylthio compounds such as cyclofuranide, phenyl ether derivatives such as 10, 10′-oxybisphenoxaarsine, and cecil. Quaternary ammonium salts such as dimethylethylammonium bromide and sulfone derivatives such as 2,3,5,6tetracolol-4- (methylsulfonyl) pyridine, amides, triazine derivatives, triazole derivatives, methylol group-containing compounds, active halogen-containing compounds, Examples include activated NS bond-containing compounds, isothiazolones, organic iodines, benzisothiazolones, and pyrithiones, but are not limited thereto.

  The antibacterial agent includes at least one of a bactericidal agent and an antibiotic. Examples of the bactericidal agent include iodine, and examples of the antibiotic include vancomycin hydrochloride, but are not limited thereto.

  In the antibacterial agent sustained-release preparation of the present invention, it is preferable that the side wall, the tip, or the opening edge of the carbon nanohorn is chemically modified to control the release rate of the encapsulated drug.

  Further, in the antibacterial agent sustained-release preparation of the present invention, the side wall, tip, or opening edge of the carbon nanohorn is hydrophobic. Chemical modification for enhancing the hydrophilicity of the carbon nanohorn or reticuloendothelium Although it has been chemically modified to avoid the phagocytosis of the system, it is preferably applied. The hydrophilicity can be obtained, for example, by chemically modifying oxygen atoms by sputtering or the like, but is not limited thereto.

  Further, in the antibacterial sustained-release preparation of the present invention, an antibody that is specifically expressed in the affected part so as to selectively reach the affected part at the side wall, tip, or opening edge of the carbon nanohorn It is preferable that a molecule that selectively adheres to a molecule is added.

  In the antibacterial sustained-release preparation of the present invention, it is preferable that a functional substance is physically adsorbed on the carbon nanohorn or the chemically modified carbon nanohorn.

  This functional substance has a controlled release of an encapsulated antibacterial agent, an antibacterial action, a drug, a hydrophilic molecule, a target molecule, and the like. An oxygen-containing molecule can be used as the hydrophilic molecule.

  The antibacterial agent sustained-release preparation of the present invention uses the antibacterial agent-encapsulated carbon nanohorn for treating skin diseases. As this antibacterial agent sustained-release preparation, it is preferable to use the antibacterial agent-encapsulated carbon nanohorn mixed with a substance having a function that facilitates application to the skin or the like.

  In the antibacterial agent sustained-release preparation of the present invention, the antibacterial agent-encapsulated carbon nanohorn is preferably administered by administration into the body for the treatment of skin diseases.

  Examples of the present invention will be described below, but the present invention is of course not limited to the following examples.

  In Example 1 of the present invention, a vancomycin hydrochloride (VCM) -encapsulated carbon nanohorn will be described.

  About 18 mg of VCM is dissolved in 100 cc of water, and about 25 mg of open-hole single-walled carbon nanohorn (SWNHox) is dispersed therein. When the dispersion was left in an atmospheric pressure nitrogen stream for 1 week, a black powder of VCM-encapsulated SWNHox (hereinafter referred to as VCM @ SWNHox) could be obtained. Encapsulated VCM was about 30-40% (0.4-0.7 g / g) by thermogravimetric analysis in He. The yield was about 95%.

  VCM @ SWNHox (1.85 mg) was dispersed in 4 ml of a buffer solution, and after a certain period of time, the supernatant was collected by centrifugation at 10,000 rpm for 5 minutes, and further filtered using a membrane having a pore size of 200 nm. The UV-visible absorption spectrum of the filtrate was measured, and the concentration of VCM was estimated from the intensity of the peak at ˜280 nm. The experiment was repeated with VCM @ SWNHox remaining at the bottom of the centrifuge tube dispersed again in 4 ml of buffer. The result is shown in FIG.

  FIG. 1 is a diagram showing the amount of VCM released from VCM @ SWNHox into a buffer solution, and the numbers in the figure indicate the measurement order of data points.

  From FIG. 1, the release of VCM from the nanohorn was special, and the amount of VCM released was low except for the VCM initial burst release (points 1 and 2 in FIG. 1) that appeared when first immersed in the buffer solution. Moreover, the release and uptake of VCM reached equilibrium within 15 minutes of buffer soaking, and the release was apparently stopped. This is an unprecedented drug release pattern, suggesting that there is no excessive release when VCM released in vivo is in the vicinity. The initial burst is caused by the dissolution of VCM attached to the outer wall of SWNHox.

  The release characteristics seem to be a preferable feature for preventing overdose in clinical practice, and it is possible to keep the drug concentration constant for at least 200 hours or more by one administration of the preparation. When administered into the blood, it is possible to maintain the antibacterial effect for a long period of time, and it is possible to greatly extend the administration interval of a drug that normally needs to be administered 1 to 4 times a day. In addition, antibacterial effect over a long period of time can be achieved by local administration to a site where MRSA infection is possible during surgery or treatment.

  Vancomycin hydrochloride is not absorbed by the intestinal tract and is used as an internal medicine for sterilization of the digestive tract during bone marrow transplantation pretreatment and treatment of some bacterial infections (necessary to take 4 times a day). By using the preparation, it is possible to prolong the administration interval and maintain a continuous antibacterial activity.

(Anti-bacteria test)
It was used for E. coli (JM101) antibacterial test. First, tryptone (DIFCO Laboratories), yeast extract (DIFCO Laboratories), NaCl, agar (BD), and water are mixed at a weight ratio of 2: 1: 2: 3: 200 to prepare an LB agar solid culture medium. Produced. The medium was autoclaved for 1.5 hours and then transferred to a culture dish (100 mm) when cooled to 50 ° C. E. coli was inoculated into LB liquid medium and cultured overnight at 37 ° C. A small portion of the bacterial solution was inoculated into individual LB plates and spread over the agar surface and then stored at 4 ° C. for later use.

  In order to investigate the activity of SWNHox containing VCM (indicated as VCM @ SWNHox), about 3 mg sample (including about 1.2 mg VCM) was placed on the agar surface inoculated with bacteria as shown in FIG. For comparison, 1.2 mg VCM and 1.8 mg SWNHox were placed in the same dish. The dish was incubated overnight at 37 ° C.

  FIG. 2 shows the results of E. coli experiments using VCM, SWNHox, and VCM @ SWNHox. The white color of the solid medium indicates the presence of E. coli. From the insert, bacteria are sterilized near VCM (Figure 2 top) and VCM @ SWNHox (Figure 2 bottom left), whereas SWNHox has no bactericidal effect on bacteria (non-toxic) It can be seen that there is a lower right figure in FIG.

  From FIG. 2, it was found that there is an inhibition ring due to the absence of bacteria around the VCM and VCM @ SWNHox samples. This indicates that VCM @ SWNHox has an effect of suppressing bacterial growth. However, SWNHox does not itself have antibiotic action.

  In Example 2 of the present invention, an iodine adsorbent using a nanohorn will be described.

1. <About iodine adsorption capacity of nanohorn>
Carbon nanohorns (CNH) were opened by hydrogen peroxide (100 ° C., 3 hours heating) treatment. Open carbon nanohorn (CNHox) (52 mg) was placed in a sealed glass container together with iodine particles (0.5 g) and allowed to stand to adsorb iodine gas to CNHox (I ₂ / CNHox). The results of examining the weight increase of CNHox due to iodine adsorption are shown in FIG. FIG. 3 shows the time dependence of the amount of iodine adsorbed on CNHox. FIG. 4 shows the Raman spectrum of I ₂ / CNHox. It was found that iodine contained in CNHox was I ⁵⁻ or I ³⁻ . G band of CNHox had about ^{8cm -1} blue shift than normal CNHox1592cm ^-1. From this, it is clear that electrons were transferred from CNHox to iodine.

2. <Iodine release from the _I 2 / CNHox>
The release of I ₂ from I ₂ / CNHox proceeded more slowly than the uptake rate. I ₂ / NHox was exposed to air at room temperature. The weight loss of the _I 2 / NHox with iodine release from I ₂ / CNHox shown in FIG. As shown in FIG. 5, the initial weight of I ₂ / CNHox was 180.5 mg (128.5 mg of I ₂ and 52 mg of CNHox). It is a result _{of I 2} was included in CNHox the 52 days. After exposure of I ₂ / CNHox to air for 64 days, its weight only decreased to 120.6 mg and still 59.9 mg of I2 remained in the CNHox. The adsorption half-life was about 2000 hours (about 83 days).

3. <Antimicrobial action of released iodine>
The antimicrobial effect of I ₂ / NHox, was studied in E. coli (colon bacilli). 26 days after the adsorption of _{I 2} in CNHox, the weight ratio of _{I 2} contained in CNHox was 2: 1. 0.15 mg of I ₂ / CNHox was placed on a culture dish on which E. coli had grown. For comparison, 20 μl water and 20 μl penicillin were dropped into the same culture dish. As shown in FIG. 6, it was found that penicillin and I ₂ / CNHox had an effect of inhibiting the growth of Escherichia coli after one day of constant temperature culture.

  As described above, in the present invention, the present invention is applied to a preparation that gradually releases an antibacterial agent by using carbon nanohorn as a carrier.

It is a figure which shows the amount of VCM discharge | released into the buffer solution from VCM @ SWNHox by Example 1 of this invention, The number in a figure has shown the measurement order of the data point. It is a photograph which shows the colon_bacillus | E._coli (E. coli) experiment result using VCM, SWNHox, and VCM @ SWNHox. The time dependence of the amount of iodine adsorbed on CNHox according to Example 2 of the present invention is shown. It is a diagram showing a Raman spectrum of the _I 2 / CNHox according to Example 2 of the present invention. It shows a weight loss of _I 2 / NHox with iodine release from _I 2 / CNHox according to Example 2 of the present invention. Is a photograph showing the penicillin and growth inhibitory effects of I _{2 /} CNHox to E. coli after the constant temperature culture day.

Claims (15)

  An antibacterial sustained-release preparation comprising a carbon nanohorn containing an antibacterial agent as a carrier.   The antibacterial sustained-release preparation according to claim 1, wherein the antibacterial agent comprises an inorganic antibacterial agent, a synthetic organic antibacterial agent, a natural product antibacterial agent, and the like.   The antibacterial sustained-release preparation according to claim 1 or 2, wherein the antibacterial agent contains at least one of a bactericidal agent and an antibiotic.   The antibacterial sustained-release preparation according to any one of claims 1 to 3, wherein the carbon nanohorn is a carbon nanohorn having an opening.   5. The antibacterial sustained release preparation according to claim 4, wherein the carbon nanohorn is subjected to chemical modification for controlling the release rate of the encapsulated drug on the side wall, tip, or edge of the opening. An antibacterial sustained release formulation.   5. The antibacterial sustained release preparation according to claim 4, wherein the carbon nanohorn is chemically modified or reticulated on a side wall, a tip, or a hole edge of the carbon nanohorn to increase the hydrophilicity of the carbon nanohorn. An antibacterial sustained-release preparation characterized by chemical modification for avoiding phagocytosis of endothelial system.   The antibacterial sustained-release preparation according to claim 4, wherein the antibody is specifically expressed in the affected part so as to selectively reach the affected part on the side wall, tip, or edge of the opening of the carbon nanohorn. A sustained release preparation of an antibacterial agent, characterized in that a molecule that selectively adheres to, etc. is added.   The antibacterial agent sustained-release preparation according to any one of claims 1 to 6, wherein a functional substance is physically adsorbed on the carbon nanohorn or the chemically modified carbon nanohorn. Preparation.   The antibacterial sustained-release preparation according to claim 8, wherein the function of the functional substance is controlled release of the encapsulated antibacterial agent, antibacterial action, drug, hydrophilic molecule, or target molecule. Antibacterial sustained release formulation.   The antibacterial agent sustained-release preparation according to any one of claims 1 to 9, wherein the antibacterial agent-encapsulated carbon nanohorn is used for skin disease treatment. .   The antibacterial agent sustained-release preparation according to any one of claims 1 to 9, or the antibacterial agent-encapsulated carbon nanohorn mixed with a substance having a function that facilitates application to the skin or the like. An antibacterial sustained-release preparation characterized by that.   10. The antibacterial agent sustained-release preparation according to any one of claims 1 to 9, wherein the antibacterial agent-encapsulated carbon nanohorn is administered and used in the body for the treatment of skin diseases. Preparation.   A method for producing a sustained-release preparation of an antibacterial agent, characterized in that carbon nanohorns are subjected to pore opening treatment as a carrier and the antibacterial agent is included.   The antibacterial sustained-release preparation according to claim 13, wherein the antibacterial agent includes an inorganic antibacterial agent, a synthetic organic antibacterial agent, a natural product antibacterial agent, and the like. A method for producing a pharmaceutical preparation.   The method for producing an antibacterial sustained-release preparation according to claim 13, wherein the antibacterial agent includes at least one of a bactericide and an antibiotic.

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