KR20110113473A - Heparin-based self-assembled nanoparticle for photosensitizer - Google Patents

Abstract

The present invention relates to a composite self-assembled nanoparticles and a biosensitizer containing the biodegradable photoactive material encapsulated, the composite self-assembled nanoparticles are heparin and biodegradable photoactive material for the inhibition of new angiogenesis and cancer growth In addition to the synergistic effect, the biodegradable photoactive substance, a hydrophobic photosensitive agent, can be efficiently delivered to cancer cells, thereby greatly contributing to the treatment of cancer through photodynamic therapy.

Description

Composite self-assembled nanoparticles encapsulated with a biodegradable photoactive material and a photosensitizer comprising the same {Heparin-based self-assembled nanoparticle for photosensitizer}

The present invention relates to composite self-assembled nanoparticles encapsulated with a biodegradable photoactive material and a photosensitizer comprising the same.

Photodynamic therapy (PDT) is a new medical technology in the treatment of cancer. The photodynamic therapy is achieved through photochemical reactions due to interactions with photosensitisers (PS), light and tissue oxygen. Photosensitizers accumulate in tumor tissues or are adsorbed by cancer cells to generate photoactivity with light of appropriate wavelengths, causing toxicity, which destroys tumor cells such as reactive oxygen species (ROS). In addition to directly killing tumor cells with free radicals, photodynamic therapy destroys tumors in two ways. Photodynamic therapy can damage the blood vessels associated with the tumor. Photodynamic therapy can also activate immune responses against tumor cells. Photosensitizers are not harmful without light and can be effectively and selectively treated without damaging normal tissues.

However, the usefulness of photodynamic therapy for the treatment of cancer is limited to the low selectivity of photosensitive agents for tumor tissue. In addition, it is difficult to make drugs with parenteral medications because most of the photosensitizers for photodynamic therapy are currently in or before clinical trials and are hydrophobic. Therefore, for the proper delivery system, it is necessary to improve the therapeutic effect and the selectivity of the photosensitizer to the tumor tissue.

Heparin is a water-soluble, sulfated polysaccharide, consisting primarily of uronic acid, which has been widely used as an anticoagulant for the past 60 years. Until now, heparin derivatives having drug delivery, new angiogenesis, and cancer growth effects have been developed by chemically or physically combining low molecular weight and high molecular compounds using heparin. Compounds have been used to treat cancer.

Therefore, the present inventors have continued to study various heparin derivatives and heparin nanoparticles having novel angiogenesis suppression, anticancer efficacy, and the possibility of drug carriers, and have a low molecular weight hydrophobic substance in heparin to the carboxy group of heparin. By chemically bonding to develop amphiphilic polymers, and found synergistic effects on the heparin and biodegradable photoactive material on cancer growth inhibition, the present invention was completed.

It is an object of the present invention to provide a composite self-assembled nanoparticle in which a biodegradable photoactive material is encapsulated in an amphiphilic polymer prepared by chemically bonding a low molecular weight hydrophobic material to heparin to a carboxy group of heparin.

It is another object of the present invention to provide a photosensitizer comprising the composite self-assembled nanoparticles.

Hereinafter, a manufacturing method of the present invention will be described in detail with reference to the accompanying drawings. The drawings introduced below are provided as examples and may be exaggerated in order to sufficiently convey the spirit of the present invention to those skilled in the art.

Hereinafter, the technical and scientific terms used herein will be understood by those skilled in the art without departing from the scope of the present invention. Descriptions of known functions and configurations that may be unnecessarily blurred are omitted.

The present invention provides a composite self-assembled nanoparticle and a composite self-assembled nanoparticle in which a biodegradable photoactive material is encapsulated in an amphipathic polymer prepared by chemically bonding a low molecular weight hydrophobic substance to heparin to a carboxy group of heparin. It provides a photosensitizer comprising a.

Hereinafter, the present invention will be described in detail.

The present invention

Provided is a composite self-assembled nanoparticles in which a biodegradable photoactive material is encapsulated in an amphiphilic polymer of Formula 1 below.

More specifically, the present invention provides composite self-assembled nanoparticles in which a biodegradable photoactive material is encapsulated in an amphiphilic polymer prepared by chemically bonding a low molecular weight hydrophobic material to heparin to a carboxy group of heparin.

In the present invention, the composite self-assembled nanoparticles of the present invention is a biodegradable photoactive material in the amphiphilic polymer of Formula 1 as pheophorbide a, hematopophyrin, Haematoporphyrin, Bacteriochlorins, One or more selected from Phthalocyanines, Benzoporphyrin derivatives, and 5-Aminolevulinic acid are used.

More specifically, the composite self-assembling nanoparticles of the present invention is characterized in that the pheophovide A of Formula 2 is encapsulated in the amphipathic polymer of Formula 1.

In the present invention, the composite self-assembled nanoparticles are characterized in that the amphiphilic polymer: biodegradable photoactive material of Formula 1 is 10: 0.1 to 3 ratio.

In the present invention, the amphiphilic polymer of Formula 1 is characterized in that the particle size of 10 to 200 nm. Please refer to Fig.

In the present invention, the composite self-assembled nanoparticles comprises the steps of preparing an amphipathic polymer of Formula 1; And encapsulating the biodegradable photoactive material in the prepared amphipathic polymer.

Amphiphilic polymer of the formula (1) is characterized in that the hydrophobic group of poly (β-benzyl L-aspartate) as a hydrophobic group in the chain of heparin is configured by introducing, the amphiphilic polymer of formula (1) is poly (β-benzyl L heparin in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of a hydrophobic block of -aspartate).

In the present invention, the hydrophobic block of the poly (β-benzyl L-aspartate) is an average molecular weight of 4500 to 5500 Da, the heparin is characterized in that the weight average molecular weight of 500 to 10,000.

As a more specific example, β-benzyl-L-aspartate-N-carboxy anhydride (BLA-NCA) using β-benzyl-L-aspartate (BLA), Trahydrofurane (THF) and triphosgene (triphosgene) ) Was synthesized and liquefied, and then mixed with dimethylformamide (dimethylformamide, DMF) and butylamine (butylamine) was reacted for 48 hours at 40 ℃ in a nitrogen atmosphere to synthesize PBLA having an average molecular weight of 4890 Da.

In order to synthesize an amphiphilic copolymer using heparin, a low molecular weight heparin (Mn: 6000) solution was prepared, and the resulting mixture was stirred for 36 hours by adding a PBLA and a coupling, and the resulting product was dialyzed for 2 days. After lyophilization and vacuum drying, an amphiphilic polymer was prepared.

In the present invention, the composite self-assembled nanoparticles are characterized in that the particle size is 10 to 200 nm.

More specifically, as a result of examining the size of the composite self-assembling nanoparticles of the present invention, it was confirmed that the length of the drug was slightly larger than that of the self-assembling nanoparticles, which were not encapsulated, which significantly affected the size of the amphiphilic polymer. This is the result of confirming. In addition, the amphiphilic polymers after the injection of the drug have their negative potential difference, it was confirmed that the electrostatically stable and negatively charged heparin shell (cell) can provide long-term stability in the physical environment. See FIG. 2.

In the present invention, it provides a photosensitizer comprising the composite self-assembled nanoparticles.

More specifically, as a result of examining the cell viability of the composite self-assembled nanoparticles of the present invention, it was confirmed that the composite self-assembled nanoparticles of the present invention are toxic to SCC7 cancer cells by themselves, and self-assembled nanoparticles. The group treated with particles showed that the cell viability was about 80% or more without photodynamic therapy and about 20% or less with photodynamic therapy. It is also confirmed that after photodynamic therapy, the phototoxic toxicity caused serious damage to cancer cells. See FIG. 5.

The composite self-assembled nanoparticles according to the present invention can not only obtain synergistic effects of heparin and biodegradable photoactive substances on new angiogenesis and inhibit cancer growth, but also provide efficient delivery of biodegradable photoactive substances which are hydrophobic photosensitive agents to cancer cells. It will make a great contribution to cancer treatment through photodynamic therapy.

1 is a result of investigating the hydrodynamic diameter (A) and particle shape (B) of the amphiphilic polymer of Preparation Example 1 according to the present invention,
2 is a result of investigating the hydrodynamic diameter (A) and morphology (B) of the composite self-assembled nanoparticles of Example 3 according to the present invention.
3 is a result of examining the absorption spectrum of the composite self-assembled nanoparticles according to the present invention,
(a: pheopovid A, b: Example 4, c: Example 3, d: Example 5, e: Example 6, f: DMSO)
Figure 4 is a result of investigating the drug in vitro release behavior from the composite self-assembled nanoparticles according to the present invention,
Figure 5 shows the results of examining the cell survival rate of the complex self-assembled nanoparticles treatment of the present invention using the SCC7 cell line,
(■: 0 J / cm 2, □: 5 J / cm 2, ▦: 10 J / cm 2)
6 is a result of examining the cytotoxicity according to the concentration of the composite self-assembled nanoparticles of Example 4 (A) and Example 6 (B) according to the present invention,
(■: 0 J / cm 2, □: 5 J / cm 2, ▦: 10 J / cm 2)
7 is a result of observing the change in cell shape according to photodynamic therapy using the composite self-assembled nanoparticles of Example 4 according to the present invention.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the following examples are only for illustrating the present invention, and the scope of the present invention is not limited thereto.

Preparation Example Preparation of Amphiphilic Polymer

First, β-benzyl-L-aspartate (BLA) was dissolved in 60 mL of dried tetrahydrofurane (THF) at 60 ° C, and 3.2 g of trihosgene was added and dissolved until it became clear. BLA-NCA Was prepared. The BLA-NCA prepared above was purified by recrystallization in cold hexane to synthesize β-benzyl-L-aspartate-N-carboxy anhydride (BLA-NCA).

6.25 g of the synthesized BLA-NCA was dissolved in 10 mL of dimethylformamide (dimethylformamide, DMF), and then 36.5 mg of butylamine dissolved in 100 mL dichloromethane (DCM) was mixed with the BLA-NCA solution. The mixture was reacted at 40 ° C. for 48 hours in a nitrogen atmosphere to synthesize PBLA having an average molecular weight of 4890 Da.

For synthesizing amphiphilic copolymer using heparin, heparin solution was prepared by dissolving low molecular weight heparin (Mn: 6000) purchased from 200 mg of Mediplex (Korea) in 5 mL of formamide.

The synthesized PBLA dissolved in 5 mL DMSO (Dimethylsulfoxide) was added to 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide (EDC) as a coupling reagent and heparin solution prepared above, followed by stirring. The content of the heparin: PBLA: EDC is shown in Table 1 below.

The resulting product was stirred for 36 hours by stirring the solution of heparin, PBLA and EDC mixed for 2 days and then lyophilized.

The unreacted reactant in the lyophilized reactant was removed with acetone and dried in vacuo to prepare an amphiphilic polymer.

[ Example ] Preparation of Composite Self-Assembly Nanoparticles

Amphiphilic polymers encapsulated with pheophorbide a of the present invention were synthesized through a dialysis method.

95 mg of each of the amphiphilic polymer (3HP) prepared in Preparation Example 1 and the amphiphilic polymer (6HP) prepared in Preparation Example 2 were added to 5 mL of DMSO (dimethylsulfoxide), and dissolved by stirring with slight heat. . To the solution in which the amphiphilic polymer is dissolved was mixed by adding a pheopovid A solution dissolved in 2 mL of DMSO. The mixing ratio of the amphiphilic polymer and pheopovidide A is shown in Table 2 below.

The mixture was dialyzed with distilled water for 2 days. The resulting product was filtered using a 0.45 μm syringe filter and then lyophilized to prepare composite self-assembled nanoparticles.

Experimental Example 1 Characterization of Amphiphilic Polymer

In order to measure the content of heparin contained in the amphipathic polymer prepared in the preparation example it was calculated using toluidine blue colorimetric method (toluidine blue colorimetric).

As can be seen from the results of Table 3, in the amphiphilic polymers of Preparation Examples 1 and 2, the coupling ratios of PBLA and heparin are 2.66 and 4.35, respectively, and the coupling ratio increases as the content of PBLA increases. there was.

In addition, the complete anticoagulant activity of the amphiphilic polymers of Preparation Examples 1 and 2 were investigated using anti-FXa chromogenic assay.

A mixture of 100 μL amphiphilic polymer solution (0.01 mg / mL) and 100 μL of anti-thrombin solution was incubated at 37 ° C. for 3 minutes, and 100 μL of FXa was added thereto for 30 seconds. After adding S-222 (200 μL, 1 mM) substrate and incubating for 3 minutes at 37 ° C., the reaction was terminated by adding 300 μL of 20% acetic acid. The product was transferred to a semi-micro cuvette and irradiated at a wavelength of 405 nm using a UV-VIS spectrophotometer (Mini-1024, SHIMADZU, Japan). Bioavailability of the amphiphilic polymers of Preparation Examples 1 and 2 was measured in comparison with the absorption wavelength of heparin.

As a result, it was confirmed that the anticoagulant activity of the amphipathic polymer of Preparation Example 85.6 and the amphiphilic polymer of Preparation Example 2 had an activity of 70.5 IU / mg. From the above results, it was confirmed that increasing the coupling ratio of PBLA decreased the anticoagulant activity of the amphiphilic polymer. This is due to the inactivation of the critical functional group of heparin or the antithrombin-bindin sequence unit, which results in lower anticoagulant activity of PBLA bound to the heparin backbone due to the altered heparin carboxyl group. will be. However, since sulfate groups, which are important for endothelial cell binding and inhibition of VEGF- and bFGF-mediated development, remain unchanged, amphiphilic polymers have an anticancer effect regardless of anticoagulant activity. It can overcome side effects such as bleeding, thrombocytopenia, and osteoporosis related to various heparin, and is preferred as an anticancer agent because of its high dosage.

The hydrodynamic diameter, zeta potential, and particle morphology of the amphipathic polymer of the above preparation were investigated.

The hydrodynamic diameter was measured using a semiconductor laser (semi-conductor laser, 655 nm) from a light source at 25 ℃ conditions at an angle of 165 ° using dynamic light scattering (ELS-Z, OTSUKA, Japan).

The zeta potential was analyzed using an electrophoretic light scattering spectrophotometer of ELS-Z, and 5 mg of drug in powder form obtained through lyophilization in 10 mL of distilled water was subjected to sonication for 0.45 light scattering analysis. Filter by μm syringe filter.

As a result, as can be seen from the results of Table 3, the amphiphilic polymers of Preparation Examples 1 and 2 were able to identify self-assembled nanoparticles having an average size of 51 nm and 66 nm, respectively, in aqueous solution, and zeta potential was -44.1. mV and -41.6 mV confirm that the presence of negatively charged heparin chains encloses self-assembled nanoparticles.

In addition, the morphology of the amphiphilic polymers of the preparation was observed at 15 kV through FE-SEM (JSM-7000F, JEOL, Japan).

As a result, as can be seen from the results of FIGS. 1 and 2, the amphiphilic polymer has a typical spherical particle distribution, and it can be confirmed that the change of the constituents of the amphiphilic polymer does not significantly affect the particle diameter and zeta potential. there was.

[ Experimental Example  2] Characterization of composite self-assembled nanoparticles

The hydrodynamic diameter, Zeta potential, and particle morphology of the composite self-assembled nanoparticles prepared in the above examples were investigated.

The hydrodynamic diameter was measured using a semiconductor laser (semi-conductor laser, 655 nm) at 25 ° C. at an angle of 165 ° using dynamic light scattering (ELS-Z, OTSUKA, Japan). The form was investigated in the same manner as in Experimental Example 1 and shown in Table 4 below.

In addition, the amount of pheophovide A encapsulated in the composite self-assembled nanoparticles prepared in the above example was measured using a colorimetric method. For analysis by colorimetric analysis, lyophilized pheophobide A-encapsulated composite self-assembled nanoparticles were dissolved until completely dissolved in 10 mL formamide, and then UV-VIS spectrophotometer was used at 669 nm wavelength. Investigate. Prepare various concentrations of pheopovid A solution, dissolve the composite self-assembled nanoparticles prepared in Example in PBS (0.01M, PH 7.4), and then absorb the spectrum using UV-VIS spectrophotometer at room temperature. It was measured by. Amphiphilic polymer without drug was used as blank sample. The spectra of pheopovid A were measured for comparison in methanol and PBS.

A calibration curve was measured at 669 nm to calculate the amount of inclusion of the drug. Drug-loading content (DLC) and drug-loading efficiency (DLE) were calculated using the above equation.

As can be seen from the results of Table 4, the drug loading concentration (%) was found to be about 1.45 to 17.53%, depending on the molar ratio of the amphiphilic polymer and the pheophobeid A. When the ratio of 10: 1 was confirmed that the drug loading concentration (%) and drug loading efficiency (%) has the lowest value.

In addition, it can be seen that the drug loading concentration (%) and drug loading efficiency (%) increases as the content of pheophovid A increases, and it is confirmed that the effective drug loading is an important condition for the content of the drug to be added. .

As a result of investigating the distribution and size of the composite self-assembled nanoparticles prepared in the above example, as shown in FIG. 2, it was confirmed that the composite self-assembled nanoparticles (3HP-Pheo15) had a typical particle distribution. The average particle size was found to be 117-189 nm. This is a result of confirming that the drug is considerably longer than the self-assembled nanoparticles without encapsulation, and that the loading of the drug has a great influence on the size of the amphiphilic polymer. In addition, the amphiphilic polymers had their negative potentials after drug encapsulation, which allowed the drug-encapsulated composite self-assembled nanoparticles to be electrostatically stable and negatively charged heparin shells for long periods of time in the physical environment. It is also the result of confirming that it can provide.

[ Experimental Example  3] Investigation of drug release from complex self-assembled nanoparticles

In The diaysis technique was used to investigate the release behavior of pheophovide A from complex self-assembled nanoparticles in vitro .

After lyophilized pheophobide A-encapsulated composite self-assembled nanoparticles prepared in the above example was sonicated with a little heat and 10 minutes to completely dissolve in 2 mL of PBS (0.01M, pH7.4), Molecular weight 2000 Da or less was put in a membrane that can be exported, soaked in 20 mL PBS and put into a thermostat shaking at 37 ℃, 50 rpm speed.

At selected time intervals, 3 mL of the solution was withdrawn from the soluble medium and lyophilized by addition of the same amount of PBS, and then mixed with 3 mL of methanol to measure the absorption value at 669 nm using a UV-VIS spectrophotometer. The amount of pheophovide A released is measured in comparison to Standard.

As a result, as can be seen from the results of Figure 4, approximately 14 to 24% of the encapsulated drug was released on the first day. This rapid release can be attributed to the degradation and release of the incorrectly encapsulated drug in the amphipathic polymer matrix. In addition, slow and sustained release was observed for 3 weeks after rapid release.

In addition, it was confirmed that the amphipathic polymer affects the release rate. That is, while Example 3 (3HP-pheo15) and Example 5 (3HP-pheo20) released 65% and 80% for 20 days, Example 4 (6HP-pheo15) and Example 6 (6HP-Pheo20) It was confirmed that 35% and 47% were released. This is because the slow release occurs because the interaction between the hydrophobic core and the drug of the amphiphilic polymer of Preparation Example 2 (6HP) is stronger than the amphiphilic polymer of Preparation Example 1 (3HP) for binding to pheophovid A It is also.

[ Experimental Example  4] Study of Cell Viability for Complex Self-Assembled Nanoparticles

Cell viability was measured using a CCK-8 assay kit using a squamous cell carcinoma (SCC7) cell line to investigate cell viability for the composite self-assembled nanoparticles prepared in the above examples.

The squamous cell carcinoma (SCC7) was purchased from the American type Culture Collection (Rockville, MD). The basal medium of the cells was 10% fetal bovine serum (FBS, GIBCO) and 1% antibiotics (P / S, GIBCO) added to RPMI 1640 (GIBCO), and 5% CO ₂ and 95% air were added to the culture vessel. It was supplied and incubated under conditions of a suitable humidity and a temperature of 37 ℃.

SCC7 (squamous cell carcinoma) cell lines were seeded in a 96-well plate at 20,000 per well and incubated for 24 hours. Subsequently, the complex self-assembled nanoparticles encapsulated with pheopovid A were diluted with fresh cell culture so as to have equivalent concentrations of pheopovid A of 0.1 M, 0.5 M and 1 M, and then 200 µl was added per well. Treatment was carried out at 37 ° C. for 4 hours. As a control, 200 µl of the cell culture solution was added per well, and the culture was performed for 4 hours. Subsequently, the cells were removed with a phosphate buffer solution to remove the cell culture medium containing the complex self-assembled nanoparticles encapsulated with pheophovide A, and to remove the complex self-assembled nanoparticles of the above example that were not absorbed into the cells. Washed twice.

After adding 200 μl of the new culture solution per well, the photodynamic therapy (PDT) treatment group used a 670 nm laser at a dose density of 50 mW / cm 2, 10 J / cm 2 and 5 J / cm 2. Photodynamic therapy was performed. After 24 hours of incubation, cell viability was measured using a CCK-8 assay kit.

As a result, as can be seen from the results of Figure 5, in the case of Preparation Example 1 (3HP) and Preparation Example 2 (6HP) it was confirmed that the cells are not toxic when the light is not irradiated. The above results were also confirmed that the amphiphilic polymer that is not encapsulated pheopovid A does not affect the cells by itself when the photodynamic therapy is not performed.

However, in the cell groups treated with the composite self-assembled nanoparticles of Examples 3 and 5, only about 30% of the cells survived without photodynamic therapy, and about 10% or less of the cells treated with photodynamic therapy. It was confirmed that the survival rate. From the above results, it was confirmed that Example 3 and Example 5 are toxic to SCC7 cancer cells by themselves. Groups treated with the composite self-assembled nanoparticles of Examples 4 and 6 showed about 80% or more cell viability without photodynamic therapy and about 20% or less with photodynamic therapy. It confirmed that it was seen.

This is a result of confirming that the cancer cells are seriously damaged by the phototoxicity after the adsorption and photodynamic therapy on the good cells.

In addition, after treating the complex self-assembled nanoparticles of Examples 4 and 6 at various concentrations, the toxicity to the cells during the photodynamic treatment of the irradiation dose (5 and 10 J / ㎠) according to the concentration was investigated . As a result, as can be seen in 6, it was confirmed that the cell viability decreased depending on the concentration of light and self-assembled composite nanoparticles.

The composite self-assembled nanoparticles of Example 4 were treated, and the cell shape and fluorescence intensity before and after photodynamic therapy were observed by confocal microscopy. As a result, as shown in FIG. 7, the composite self-assembled nanoparticles of Example 4 were absorbed by the cells to give a strong fluorescence signal to the inside of the cell and the nuclear membrane, and the shape of the cells was normal before the photodynamic treatment, but after the treatment. The cells swell like balloons and numerous bubbles can be observed.

Claims (11)

Composite self-assembled nanoparticles in which a biodegradable photoactive material is encapsulated in an amphiphilic polymer of the formula (1).

The method of claim 1,
The biodegradable photoactive materials are pheophorbide a, hematopophyrin, Haematoporphyrin, bacteriochlorins, Phthalocyanines, benzopophyrin derivatization, and 5-aminoeburinic. Complex self-assembling nanoparticles of any one or more selected from 5-Aminolevulinic acid. The method of claim 1,
The composite self-assembling nanoparticles are composite self-assembling nanoparticles of the amphipathic polymer: biodegradable photoactive material of Formula 1 in a ratio of 10: 0.1 to 3. The method of claim 3, wherein
The composite self-assembling nanoparticles is prepared by the amphipathic polymer of Formula 1; And encapsulating a biodegradable photoactive material in the prepared amphipathic polymer. The method of claim 1,
The composite self-assembled nanoparticles are composite self-assembled nanoparticles having a particle size of 10 to 200 nm. The method of claim 4, wherein
Amphiphilic polymer of Formula 1 is a composite self-assembling nanoparticles composed by introducing a hydrophobic block of poly (β-benzyl L-aspartate) as a hydrophobic group in the chain of heparin. The method of claim 6,
Amphiphilic polymer of Formula 1 is a composite self-assembled nanoparticles composed of 0.1 to 10 parts by weight of heparin with respect to 100 parts by weight of hydrophobic block of poly (β-benzyl L-aspartate). The method of claim 7, wherein
The hydrophobic block of the poly (β-benzyl L-aspartate) is a composite self-assembled nanoparticles having an average molecular weight of 4500 to 5500 Da. The method of claim 7, wherein
The heparin is a composite self-assembled nanoparticles having a weight average molecular weight of 500 to 10,000. The method of claim 6,
Amphiphilic polymer of Formula 1 is a composite self-assembling nanoparticles having a particle size of 10 to 200 nm. A photosensitizer comprising the composite self-assembled nanoparticle of any one of claims 1 to 10.

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