A monomolecular micelle aqueous solution, its preparation method and application

Abstract

The present application relates to a kind of monomolecular micelle aqueous solution and its preparation method and application, biological medical technical field.The monomolecular micelle aqueous solution of the present application is formed by amphiphilic polyether ester multi-block copolymer in aqueous phase.Assembly into monomolecular micelle by slowly adding deionized water to amphiphilic multi-block copolymer dissolved in good solvent, or slowly drop into a large amount of deionized water, remove good solvent in water by dialysis, obtain monomolecular micelle aqueous solution.Amphiphilic polyether ester multi-block copolymer has good biocompatibility and degradability.The monomolecular micelle prepared in the present application has excellent stability, and will not dissociate with the dilution of polymer concentration, solve the problem that the micelle commonly used at present will dissociate with the dilution of polymer concentration.The monomolecular micelle prepared in the present application has good solubilization effect on water-insoluble drugs, and can be used in the fields of drug extraction, drug delivery and controlled release.

Description

Technical Field

[0001] This invention relates to the field of biomedical technology, and in particular to a single-molecule micelle aqueous solution, its preparation method, and its application. Background Technology

[0002] In recent years, polymer micelles as carriers for cancer therapy have attracted widespread attention. Polymer micelles are typically composed of block copolymer molecules, exhibiting good biocompatibility and excellent ability to dissolve hydrophobic anticancer drugs. Simultaneously, polymer micelles with suitable sizes (10-150 nanometers) can utilize the enhanced permeability and retention (EPR) effect at the tumor site to accumulate and achieve passive targeted therapy. Therefore, polymer micelles are considered one of the most promising nanomedicine carrier systems. However, traditional polymer micelles formed by the self-assembly of diblock or triblock copolymers, after being injected into the human body, tend to dissociate and release the loaded drug due to dilution. This can reduce efficacy and, moreover, cause damage to healthy tissues or cells due to premature drug release. These factors limit the application of polymer micelles in cancer therapy.

[0003] To overcome the problem of insufficient micelle stability, researchers have explored various strategies, one of which is to improve the structural stability of micelles by introducing crosslinkable groups into the core or shell to form covalent bonds. For example, Biswas et al. designed an ABA-type triblock copolymer containing disulfide bonds, which formed micelles that maintained colloidal stability under blood dilution and achieved rapid drug release under intracellular glutathione stimulation for tumor-targeted chemotherapy [D. Biswas, Molecular Pharmaceutics 2017, 14 (8), 2518-2528]. However, the crosslinking process is far more complex than the formation of ordinary micelles, and current research is only at the preclinical research stage.

[0004] Proteins in living organisms can specifically bind to certain drugs, and these drugs are not released with dilution. This is because proteins can fold into single molecules, which can be considered as forming monomolecular micelles. Therefore, monomolecular micelles hold promise for solving the problem of insufficient micelle stability. Furthermore, monomolecular micelles typically have a diameter of only 10-30 nm, much smaller than micelles composed of multiple molecules, which facilitates drug penetration into diseased tissues. Moreover, monomolecular micelles are not destroyed by changes in concentration, temperature, or other factors, allowing them to remain stable even at extremely low concentrations, thus offering unique advantages in the biomedical field.

[0005] Currently, the polymers that can form monomolecular micelles are mainly dendritic polymers. Fan et al. synthesized an RGD peptide-modified dendritic macromolecular amphiphilic copolymer, which can self-assemble into monomolecular micelles in aqueous solution and efficiently load the hydrophobic anticancer drug doxorubicin (DOX), exhibiting excellent pH-responsive drug release behavior, thereby achieving targeted therapy [X. Fan, Journal of Materials Chemistry B 2017, 5, 1062-1072]. However, dendritic polymers have problems such as complex synthesis methods, low synthesis efficiency leading to high costs, and slow degradation rate in vivo due to their special structure, resulting in slow drug release rate. These issues pose potential risks and problems in clinical applications, preventing their practical application.

[0006] Based on the above analysis, there is a need to develop monomolecular micelles with small particle size, capable of loading hydrophobic drugs and remaining stable under dilution conditions in a circulating system. These monomolecular micelles would have significant implications for cancer treatment. Summary of the Invention

[0007] To address the aforementioned technical problems, this invention provides a monomolecular micelle aqueous solution, its preparation method, and its applications. Given that multiblock copolymers are more easily folded and their hydrophilic segments can stabilize insoluble blocks, they are theoretically more likely to form monomolecular micelles than diblock copolymers. This method uses an amphiphilic polyether ester multiblock copolymer, which self-assembles in an aqueous solution to prepare monomolecular micelles with a smaller particle size than the multiblock copolymer in a good solvent. The polyether ester multiblock copolymer used is composed of aliphatic polyether blocks and aliphatic polyester blocks, thus possessing good biocompatibility and degradability. The prepared monomolecular micelle aqueous solution, through the microphase formed by the aliphatic polyester, exhibits good solubilizing effect on hydrophobic drugs, preventing drug release regardless of concentration changes. Furthermore, under the catalysis of enzymes, the aliphatic polyester blocks can degrade, thereby destroying the monomolecular micelles and releasing the drug. The monomolecular micelles prepared by this invention are small in size, allowing for passive targeted tumor therapy by utilizing the EPR effect at the tumor site.

[0008] This invention is achieved through the following technical solution:

[0009] The first objective of this invention is to provide a monomolecular micelle aqueous solution, which is formed by the self-assembly of a linear amphiphilic multiblock copolymer in an aqueous phase. The amphiphilic polyether ester multiblock copolymer has a high molecular weight and a high number of blocks, and its chemical structural formula is as follows:

[0010] ,

[0011] Where a is any integer from 2 to 4, b is any integer from 2 to 11, c is any integer from 22 to 90, m is any integer from 1 to 3, and n is any integer greater than 2.

[0012] In one embodiment of the present invention, the particle size of the micelles in the monomolecular micelle solution is smaller than the particle size of the polyether ester multiblock copolymer in a good solvent; indicating that monomolecular micelles are formed. Their average hydrodynamic diameter is less than 30 nanometers.

[0013] The good solvent is one or more of tetrahydrofuran, N,N-dimethylformamide, and dimethyl sulfoxide.

[0014] In one embodiment of the present invention, the concentration of the monomolecular micelle solution is 0.1 mg / mL to 10 mg / mL.

[0015] In one embodiment of the present invention, the amphiphilic polyether ester multiblock copolymer includes polyether blocks and polyester blocks; the polyether blocks are polyethylene glycol blocks; and the polyester blocks are aliphatic polyester blocks.

[0016] The mass ratio of polyether blocks to polyester blocks in the amphiphilic polyether ester multiblock copolymer is 2:1 to 5:1;

[0017] The amphiphilic polyether ester multiblock copolymer has biodegradable properties.

[0018] In one embodiment of the present invention, the molecular weight of the macromolecular initiator polyethylene glycol is 2 kg / mol to 4 kg / mol.

[0019] In one embodiment of the present invention, the molecular weight of the multiblock copolymer reaches 20 kg / mol to 100 kg / mol.

[0020] In one embodiment of the present invention, the aqueous phase is water and / or deuterated water.

[0021] The second objective of this invention is to provide a method for preparing the monomolecular micelle aqueous solution, comprising the following steps: dissolving an amphiphilic polyether ester multiblock copolymer in a good solvent to obtain a polyether ester multiblock copolymer solution; slowly adding an aqueous phase to the obtained polyether ester multiblock copolymer solution for dilution, thereby self-assembling into monomolecular micelles; and removing the good solvent from the solution by dialysis to obtain a monomolecular micelle solution.

[0022] Alternatively, the amphiphilic polyether ester multiblock copolymer is dissolved in a good solvent to obtain a polyether ester multiblock copolymer solution; the obtained polyether ester multiblock copolymer solution is added dropwise to an aqueous phase, where it self-assembles into monomolecular micelles; the good solvent in the solution is removed by dialysis to obtain an aqueous solution of monomolecular micelles.

[0023] In one embodiment of the present invention, the good solvent is one or more selected from N,N-dimethylformamide, tetrahydrofuran, and dimethyl sulfoxide; the good solvent is miscible with water;

[0024] The concentration of the polyether ester multiblock copolymer in the polyether ester multiblock copolymer solution is 1 mg / mL to 100 mg / mL.

[0025] A third objective of this invention is to provide the application of the monomolecular micelle aqueous solution in drug loading, wherein a hydrophobic drug is loaded onto the monomolecular micelle aqueous solution to obtain a drug-loaded monomolecular micelle solution, wherein the monomolecular micelle aqueous solution has a solubilizing effect on the hydrophobic drug.

[0026] In one embodiment of the present invention, the drug-loaded monomolecular micelle aqueous solution does not release the drug upon dilution, thus exhibiting stability.

[0027] In one embodiment of the present invention, the drug-loaded monomolecular micelle aqueous solution releases a hydrophobic drug under the action of an enzyme; the monomolecular micelles in the monomolecular micelle solution are biodegradable.

[0028] In the prior art, the polymers used to prepare monomolecular micelles are usually dendritic polymers. Such polymers and the monomolecules prepared from them usually have problems such as complex synthesis steps, low yield, difficulty in degradation in the human body, or slow drug release rate.

[0029] The technical solution of the present invention has the following advantages compared with the prior art:

[0030] 1. This invention provides a monomolecular micelle aqueous solution, its preparation method, and its application. The monomolecular micelles prepared by this invention exhibit good stability in water; the micelles do not dissociate with changes in concentration, thus preventing the release of the loaded drug upon dilution. In contrast, micelles formed by the self-assembly of traditional diblock and triblock copolymers, which are formed by the aggregation of multiple polymer chains, dissociate upon dilution, leading to drug release.

[0031] 2. The single-molecule micelles of the present invention have a smaller particle size than the multi-block copolymers in good solvents, and their average hydrodynamic diameter is usually less than 30 nanometers. Therefore, they are easy to accumulate at the tumor site and achieve passive targeted therapy.

[0032] 3. The present invention prepares monomolecular micelles from aliphatic polyether ester multiblock copolymers, wherein both the aliphatic polyester and the aliphatic polyether blocks have good biocompatibility and can be used in vivo;

[0033] 4. The monomolecular micelles prepared by this invention have good solubilizing ability for drugs that are insoluble in water;

[0034] 5. The monomolecular micelles prepared by this invention are biodegradable, and the monomolecular micelles loaded with hydrophobic drugs can release the hydrophobic drugs under the action of lipases. Attached Figure Description

[0035] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein:

[0036] Figure 1 This is a schematic diagram of the assembly of single-molecule micelles in this invention;

[0037] Figure 2 The results of dynamic light scattering tests are for the single-molecule micelle solution M-1 prepared in Example 1 of this invention.

[0038] Figure 3 The results of dynamic light scattering tests of the amphiphilic polyether ester multiblock copolymer mBCP-1 prepared in Example 1 of this invention in its good solvent tetrahydrofuran;

[0039] Figure 4 The transmission electron microscope test results are those of the single-molecule micelle solution M-1 prepared in Example 1 of this invention;

[0040] Figure 5 The NMR diffusion sequence spectrum of the amphiphilic polyether ester multiblock copolymer mBCP-1 in its good solvent deuterated chloroform is shown in Example 2 of this invention.

[0041] Figure 6 The nuclear magnetic diffusion sequence spectrum of the monomolecular micelle solution M-2 prepared from the amphiphilic polyether ester multiblock copolymer mBCP-1 in its selective solvent deuterium water in Example 2 of the present invention;

[0042] Figure 7 The results of dynamic light scattering tests are for the single-molecule micelle solution M-3 prepared in Example 3 of this invention;

[0043] Figure 8 The results of dynamic light scattering tests are for the single-molecule micelle solution M-4 prepared in Example 4 of this invention.

[0044] Figure 9 The results of dynamic light scattering tests are for the single-molecule micelle solution M-5 prepared in Example 5 of this invention.

[0045] Figure 10 The results of dynamic light scattering tests are for the single-molecule micelle solution M-6 prepared in Example 6 of this invention.

[0046] Figure 11 The results of dynamic light scattering tests are for the single-molecule micelle solution M-7 prepared in Example 7 of this invention.

[0047] Figure 12 The results of dynamic light scattering tests are for the single-molecule micelle solution M-8 prepared in Example 8 of this invention.

[0048] Figure 13 The results of the UV-Vis absorption spectrum test of the solution after mixing curcumin with single-molecule micelle solution M-1 and deionized water in Test Example 1 of this invention;

[0049] Figure 14 The results of dynamic light scattering tests on curcumin before and after solubilization by the single-molecule micelle solution M-1 in Test Example 1 of this invention are shown.

[0050] Figure 15 The results of the UV-Vis absorption spectrum test of the solution after continuous dilution of the drug-loaded single-molecule micelle M-1 in Test Example 1 of this invention;

[0051] Figure 16 The UV-Vis absorption spectrum test results of curcumin released by enzymes after drug loading in the single-molecule micelle solution M-4 in Test Example 2 of this invention;

[0052] Figure 17 The results of dynamic light scattering tests are shown for the triblock copolymer micelles Tri-M prepared in Comparative Example 1 of this invention.

[0053] Figure 18 The results of UV-Vis absorption spectroscopy tests on the Tri-M drug-loaded solution and its diluted solution in Test Example 3 of this invention are shown. Detailed Implementation

[0054] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0055] Unless otherwise specified, the experimental methods used in the following examples are conventional methods, and the materials and reagents used are commercially available.

[0056] The CAS numbers of the organic reagents used in this invention are listed below:

[0057] Table 1

[0058]

[0059] In the following embodiments of the present invention, the amphiphilic polyether ester multiblock copolymer is prepared by ring-opening-condensation cascade polymerization, specifically referring to patent CN115260460A - A copolyester and its preparation method. A common synthesis method is as follows: an aliphatic cyclic ester (musk T, cyclic oligobutylene succinate or cyclic oligoethylene adipate), polyethylene glycol, and a catalyst (tetrabutyl titanate) are mixed, purged with nitrogen, heated to 220 °C-240 °C, and polymerized under nitrogen or vacuum for a certain time to obtain the amphiphilic polyether ester multiblock copolymer.

[0060] In the following embodiments of the present invention, a solvent exchange method is used to prepare monomolecular micelles.

[0061] In the following embodiments of the present invention, a Brookhaven BI-200SM laser light scattering instrument was used to perform dynamic light scattering (DLS) tests on single-molecule micelles (temperature: 25 °C, wavelength: 637 nm, time: 10~15 min).

[0062] In the following embodiments of the present invention, the diffusion coefficients of the amphiphilic polyether ester multiblock copolymer in a good solvent (deuterated chloroform) and a selective solvent (deuterated water) were tested using nuclear magnetic resonance diffusion sequence spectroscopy (DOSY) of Agilent Direct-Drive II 600 MHz (temperature: 25 °C).

[0063] In the following embodiments of the present invention, the morphology of single-molecule micelles was measured using a Hitachi HT7700 transmission electron microscope (TEM).

[0064] In the following embodiments of the present invention, a Shimadzu UV-1800 spectrophotometer was used to perform UV-Vis absorption spectroscopy on the monomolecular micelle solubilized samples (temperature: room temperature).

[0065] Example 1

[0066] This embodiment provides a monomolecular micelle aqueous solution and its preparation method. The polyether ester multiblock copolymer mBCP-1 sample used was obtained by ring-opening-condensation cascade polymerization of polyethylene glycol (PEO, molecular weight 2000 g / mol) and musk T, with a molecular weight of 68.9 kg / mol, a polyether to polyester weight ratio of 3.5:1, and an average number of blocks of 55 (n = 27). Details are as follows:

[0067] 100 mg of mBCP-1 sample was weighed and dissolved in 10 mL of N,N-dimethylformamide (DMF) overnight. With stirring, 40 mL of deionized water was added dropwise to the DMF solution containing the polymer at a rate of 6 mL / h to prepare a micelle solution with a concentration of 2 mg / mL. The prepared micelle solution was dialyzed in deionized water, with the deionized water changed every 12 h for a total of 4 days. After dialysis, monomolecular micelle solution M-1 was obtained (see schematic diagram of monomolecular micelle assembly as shown). Figure 1 (As shown).

[0068] Figure 2 The results are from DLS analysis of the monomolecular micelle solution M-1. The average hydrodynamic diameter of the prepared monomolecular micelles is 13.6 nm.

[0069] Figure 3 The particle size of mBCP-1, measured by DLS in the good solvent tetrahydrofuran (THF), is 20.4 nm, which is larger than the diameter of the micelles in M-1. Since polymers are dispersed as monomolecules in a good solvent in dilute solutions, this indicates that monomolecular micelles are formed in water.

[0070] Figure 4 These are the TEM test results of the single-molecule micelle solution M-1. The average diameter of the prepared single-molecule micelles is about 13 nm.

[0071] Example 2

[0072] This embodiment provides a monomolecular micelle aqueous solution and its preparation method. The preparation method of micelles provided in this embodiment is similar to that in Example 1, except that deuterium water is used instead of deionized water to obtain monomolecular micelle deuterium aqueous solution M-2.

[0073] Figure 5 The diagram shows the DOSY curve of mBCP-1 in its good solvent, deuterated chloroform, with a measured diffusion coefficient of 0.561 × 10⁻⁶. -10 m 2 / s, from the Stokes-Einstein equation (D = kT / 6πηR h The hydrodynamic radius is 6.1 nm, where k is the Boltzmann constant, T is the thermodynamic temperature, and η is the viscosity of the solvent.

[0074] Figure 6 The image shows the DOSY diagram of mBCP-1 in its selective solvent, deuterium water, with a measured diffusion coefficient of 0.214 × 10⁻⁶. -10 m 2The hydrodynamic radius of the sample is 5.8 nm, obtained from the Stokes-Einstein equation. This is smaller than the hydrodynamic radius of the sample in the good solvent deuterated chloroform, indicating that the sample formed in deuterated water is a monomolecular micelle.

[0075] Example 3

[0076] This embodiment provides a monomolecular micelle aqueous solution and its preparation method. The preparation method of the micelles provided in this embodiment is similar to that in Example 1, except that: a polyether ester multiblock copolymer mBCP-2 is used instead of mBCP-1; a monomolecular micelle solution M-3 is prepared.

[0077] The preparation method of the polyether ester multiblock copolymer mBCP-2 sample is similar to that of mBCP-1, except that the polymerization time is shorter than that of mBCP-1. The resulting polyether ester multiblock copolymer has a molecular weight of 32.4 kg / mol and an average number of blocks of 27 (n = 13).

[0078] Figure 7 The results are from the DLS test of the monomolecular micelle solution M-3, showing that the average diameter of the prepared monomolecular micelles is 14.4 nm.

[0079] Example 4

[0080] This embodiment provides a single-molecule micelle aqueous solution and its preparation method. The preparation method of the micelles provided in this embodiment is similar to that in Example 1, except that: a polyether ester multiblock copolymer mBCP-3 is used instead of mBCP-1; the amount of mBCP-3 sample added is 250 mg; and a single-molecule micelle solution M-4 with a concentration of 5 mg / mL is obtained.

[0081] The preparation method of polyether ester multiblock copolymer mBCP-3 is similar to that of mBCP-1, with the only difference being that the mBCP-3 sample was obtained by ring-opening-condensation cascade polymerization of polyethylene glycol (PEO, molecular weight 3000 g / mol) and musk T, with a molecular weight of 63.5 kg / mol, a polyether to polyester weight ratio of 4.5:1, and an average number of blocks of 35 (n = 17).

[0082] Figure 8 The results are from the DLS test of the monomolecular micelle solution M-4. The average diameter of the prepared monomolecular micelles is 26.8 nm.

[0083] Example 5

[0084] This embodiment provides a single-molecule micelle aqueous solution and its preparation method. The preparation method of the micelles provided in this embodiment is similar to that in Example 1, except that the solvent N,N-dimethylformamide (DMF) is replaced with dimethyl sulfoxide (DMSO); the amount of mBCP-1 sample added is 25 mg; thus, a single-molecule micelle solution M-5 with a concentration of 0.5 mg / mL is prepared.

[0085] Figure 9 The results are from the DLS test of the monomolecular micelle solution M-5, showing that the average diameter of the prepared monomolecular micelles is 13.8 nm.

[0086] Example 6

[0087] This embodiment provides a monomolecular micelle aqueous solution and its preparation method. The preparation method of the micelles provided in this embodiment is similar to that in Example 1, except that: a polyether ester multiblock copolymer mBCP-4 is used instead of mBCP-1; and the solvent N,N-dimethylformamide (DMF) is replaced with tetrahydrofuran (THF). A monomolecular micelle solution M-6 with a concentration of 2 mg / mL is thus prepared.

[0088] The preparation method of the mBCP-4 sample used was similar to that of mBCP-1, with the only difference being that the molecular weight of the obtained polymer was 80.3 kg / mol, the weight ratio of polyether to polyester was 3:1, and the average number of blocks was 61 (n = 30).

[0089] Figure 10 The results are from the DLS test of the monomolecular micelle solution M-6, showing that the average diameter of the prepared monomolecular micelles is 12.5 nm.

[0090] Example 7

[0091] This embodiment provides a monomolecular micelle aqueous solution and its preparation method. The preparation method of the micelles provided in this embodiment is similar to that in Example 1, except that a polyether ester multiblock copolymer mBCP-5 is used instead of mBCP-1. A monomolecular micelle solution M-7 with a concentration of 2 mg / ml is prepared.

[0092] The preparation method of mBCP-5 is similar to that of mBCP-1, with the only difference being that the mBCP-5 sample is obtained by ring-opening-condensation cascade polymerization of polyethylene glycol (PEO, molecular weight 2000 g / mol) and cyclic oligobutyl succinate, with a molecular weight of 45.0 kg / mol, a polyether to polyester weight ratio of 3.5:1, and an average number of blocks of 35 (n = 17).

[0093] Figure 11 The results are from the DLS test of the monomolecular micelle solution M-7, showing that the average diameter of the prepared monomolecular micelles is 13.6 nm.

[0094] Example 8

[0095] This embodiment provides a monomolecular micelle aqueous solution and its preparation method. The preparation method of the micelles provided in this embodiment is similar to that in Example 1, except that a polyether ester multiblock copolymer mBCP-6 is used instead of mBCP-1. A monomolecular micelle solution M-8 with a concentration of 2 mg / mL is obtained.

[0096] The preparation method of mBCP-6 is similar to that of mBCP-1, with the only difference being that the mBCP-6 sample is obtained by ring-opening-condensation cascade polymerization of polyethylene glycol (PEO, molecular weight 1500 g / mol) and cyclic oligomeric polyethylene adipate, with a molecular weight of 55.5 kg / mol, a polyether to polyester weight ratio of 4:1, and an average number of blocks of 61 (n = 30).

[0097] Figure 12 The figure shows the DLS test results of the monomolecular micelle solution M-8. As can be seen from the figure, the average diameter of the prepared monomolecular micelles is 7.9 nm.

[0098] Test Example 1

[0099] This test case demonstrates the solubilizing ability of monomolecular micelle solutions for hydrophobic drugs and the stability of drug-loaded monomolecular micelles under dilution conditions, as detailed below:

[0100] Take 10 mL of the single-molecule micelle solution M-1 sample from Example 1 and 10 mL of deionized water as a control sample, add 0.5 mg of curcumin to each, and stir at room temperature for 24 h. Measure the UV-vis absorption spectra of the corresponding solutions, as shown below. Figure 13 As shown in the figure, an absorption peak of curcumin appeared in the solution of the single-molecule micelle sample, with a concentration of approximately 4.78 μg / mL. However, curcumin is insoluble in water and did not show a corresponding absorption peak, indicating that the prepared single-molecule micelles have excellent solubilizing ability for the hydrophobic drug curcumin.

[0101] Figure 14 The figure shows the DLS test results of the single-molecule micelle solution M-1 loaded with curcumin. As can be seen from the figure, the average diameter of the single-molecule micelles after loading with curcumin is 14.2 nm, which is not much different from the average diameter before solubilization (13.6 nm).

[0102] The stability of the curcumin-loaded single-molecule micelle solution M-1 was investigated by dilution and UV-vis testing. Figure 15These are the UV-Vis curves of the samples before and after dilution. The absorbance before dilution was 0.105. After a two-fold dilution, the theoretical absorbance calculated based on the concentration dilution was 0.0525, and the actual absorbance was 0.0521. After a five-fold dilution, the theoretical absorbance was 0.0210, and the actual absorbance was 0.0199. The measured absorbance after dilution is close to the theoretical absorbance, indicating that the single-molecule micelles loaded with curcumin do not release the loaded drug upon dilution.

[0103] Test Example 2

[0104] This test case demonstrates the release of hydrophobic drugs by unimolecular micelle solutions under enzymatic action, as detailed below:

[0105] Take the single-molecule micelle solution M-4 sample from Example 4, add 0.5 mg of curcumin to it and stir to solubilize it for 2 h, then filter to remove free curcumin and add lipase PS with an enzyme concentration of 1 mg / mL, and place it in a shaker at 45 °C for 24 h.

[0106] Figure 16 The figures show the UV-vis values ​​at 0 h and 24 h after the addition of lipase. As can be seen from the figure, after 24 h of lipase addition, the UV absorption curve of curcumin decreased significantly (the peak value decreased from 0.609 to 0.307), indicating that the monomolecular micelles were degraded under the action of the enzyme, thereby releasing curcumin.

[0107] Comparative Example 1

[0108] This comparative example provides an aqueous solution of triblock copolymer micelles. The triblock copolymer tri-BCP sample used was obtained by ring-opening polymerization of polyethylene glycol (PEO, molecular weight 2000 g / mol) and musk T, with a molecular weight of 2.6 kg / mol and a polyether to polyester weight ratio of 3.5:1. Its structure is similar to mBCP-1, but it is a triblock copolymer (i.e., n = 1). The triblock copolymer micelle solution tri-M with a concentration of 2 mg / mL was prepared according to the micelle preparation method in Example 1.

[0109] Figure 17 The figure shows the DLS test results of tri-M micelles prepared from the tri-BCP copolymer sample. As can be seen from the figure, the average diameter of the prepared micelles is 79.6 nm, which is much larger than the particle size in a good solvent, indicating that a micelle solution composed of aggregates of multiple molecules was formed.

[0110] Test Example 3

[0111] The solubilizing ability of the micelle solution prepared from the tri-BCP copolymer in Comparative Example 1 for hydrophobic drugs and the stability of the micelles under dilution conditions after drug loading are as follows:

[0112] Take 10 mL of the micelle solution tri-M sample from Comparative Example 1, add 0.5 mg of curcumin, and stir at room temperature for 24 h. Measure the UV-vis absorption spectrum of the solution, as shown below. Figure 18 As shown in the figure, an absorption peak of curcumin appeared in the Tri-M micelle sample solution, with a concentration of 3.53 μg / mL, indicating that the prepared micelles have a solubilizing effect on the hydrophobic drug curcumin.

[0113] The above solution was diluted and UV-vis tests were performed. The UV-vis curves of the samples before and after dilution are shown below. Figure 18 As shown, the absorbance before dilution was 0.488. After a two-fold dilution, the theoretical absorbance should be 0.244, but the actual absorbance was 0.202. After a five-fold dilution, the theoretical absorbance should be 0.0976, but the actual absorbance was 0.0637. The actual absorbance after dilution is less than the theoretical absorbance calculated based on concentration dilution, indicating that after the micelles assembled from the triblock copolymer are loaded with curcumin, the micelles will dissociate upon dilution, thereby releasing the loaded drug.

[0114] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A single-molecule micelle aqueous solution, characterized in that, The monomolecular micelle aqueous solution is formed by the self-assembly of an amphiphilic polyether ester multiblock copolymer in an aqueous phase; the chemical structural formula of the amphiphilic polyether ester multiblock copolymer is as follows: ， Where a is any integer from 2 to 4, b is any integer from 2 to 11, c is any integer from 22 to 90, m is any integer from 1 to 3, and n is any integer from 13 to 30; The mass ratio of polyether blocks to polyester blocks in the amphiphilic polyether ester multiblock copolymer is 2:1 to 5:

1. The molecular weight of the amphiphilic polyether ester multiblock copolymer is 20 kg / mol to 100 kg / mol; The method for preparing the monomolecular micelle aqueous solution is characterized by comprising the following steps: dissolving an amphiphilic polyether ester multiblock copolymer in a good solvent to obtain a polyether ester multiblock copolymer solution; slowly adding an aqueous phase to the obtained polyether ester multiblock copolymer solution for dilution, and self-assembling into monomolecular micelles; removing the good solvent from the solution by dialysis to obtain a monomolecular micelle solution; Alternatively, the amphiphilic polyether ester multiblock copolymer is dissolved in a good solvent to obtain a polyether ester multiblock copolymer solution; the obtained polyether ester multiblock copolymer solution is added dropwise to an aqueous phase, where it self-assembles into monomolecular micelles; the good solvent in the solution is removed by dialysis to obtain an aqueous solution of monomolecular micelles. The good solvent is one or more of N,N-dimethylformamide, tetrahydrofuran, and dimethyl sulfoxide.

2. The unimolecular micelle aqueous solution according to claim 1, characterized in that, The particle size of the micelles in the monomolecular micelle solution is smaller than that of the polyether ester multiblock copolymer in a good solvent.

3. The unimolecular micelle aqueous solution according to claim 1, characterized in that, The concentration of the monomolecular micelle solution is 0.1 mg / mL to 10 mg / mL.

4. The unimolecular micelle aqueous solution according to claim 1, characterized in that, The amphiphilic polyether ester multiblock copolymer includes polyether blocks and polyester blocks; the polyether blocks are polyethylene glycol blocks; and the polyester blocks are aliphatic polyester blocks. The amphiphilic polyether ester multiblock copolymer has biodegradable properties.

5. The unimolecular micelle aqueous solution according to claim 1, characterized in that, The aqueous phase is water and / or deuterated water.

6. The unimolecular micelle aqueous solution according to claim 1, characterized in that, The concentration of the polyether ester multiblock copolymer in the polyether ester multiblock copolymer solution is 1 mg / mL to 100 mg / mL.

7. The use of the monomolecular micelle aqueous solution according to any one of claims 1-5 in the preparation of a drug, characterized in that, A hydrophobic drug is loaded onto a monomolecular micelle aqueous solution to obtain a drug-loaded monomolecular micelle solution. The monomolecular micelle aqueous solution has a solubilizing effect on the hydrophobic drug. The hydrophobic drug is curcumin.

8. The application according to claim 7, characterized in that, The drug-loaded monomolecular micelle aqueous solution does not release the drug upon dilution, thus exhibiting stability.

9. The application according to claim 7, characterized in that, The drug-loaded monomolecular micelle aqueous solution releases the hydrophobic drug under the action of enzymes; the monomolecular micelles in the monomolecular micelle solution are biodegradable.

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