Method for producing ultrasound-responsive drug carrier for drug delivery and ultrasound-responsive drug carrier using same

Abstract

Disclosed are a method for producing an ultrasound-responsive drug carrier for delivering a drug and an ultrasound-responsive drug carrier produced by the method, the method comprising: (a) obtaining a drug-ion conjugate using an acidic compound and the drug; and (b) generating the ultrasonic response drug carrier by using the drug-ion conjugate, drug carrying oil, an inert gas and a phospholipid.

Description

Technical Field

[0001] The present invention relates to a method for generating a drug carrier and a drug carrier using the method, and in particular, to a method for generating an ultrasound-responsive drug carrier for effectively delivering drugs and an ultrasound-responsive drug carrier using the method. Background Art

[0002] A drug delivery system (DDS) can be described as a dosage formulation that effectively delivers the required dose of a drug to treat a disease by minimizing the efficacy and effect of the drug.

[0003] Such drug delivery systems include transdermal, oral, or vascular methods depending on the drug delivery route. In addition, drug delivery systems that treat the affected area by introducing microcapsules into blood vessels are attracting attention as an ideal treatment technology for the future.

[0004] In addition, it can be said that the basic technology in drug delivery system technology is the technology of accurately targeting the drug to the target affected part and the technology of controlling the release of the drug in the affected part. Therefore, targeted drug delivery systems using ultrasound and ultrasound-responsive drug carriers have received increasing attention in recent years as technologies that can solve these problems.

[0005] In particular, microbubbles used as ultrasound contrast agents undergo cavitation due to ultrasound energy, and studies have shown that this phenomenon improves the effect of drug delivery to the skin or inside cells, so people have tried to bind ligands to drugs or receptors in the microbubble membrane to deliver drugs to the human body.

[0006] However, this method binds drugs on the membrane surface, so there is a possibility that drugs will be lost during the movement of microbubbles to the target location, thus failing to fully play the role of drug carrier. In addition, there is also the limitation that a large amount of drugs cannot be loaded.

[0007] Therefore, an improved solution that can solve the above problems is needed. Summary of the invention

[0008] Technical problem to be solved by the invention

[0009] The present invention aims to solve all the above problems.

[0010] Furthermore, another object of the present invention is to protect drugs from the external environment by loading the drugs into the interior of the ultrasound-responsive drug carrier.

[0011] In addition, another object of the present invention is to enable an ultrasound-responsive drug carrier to exhibit significant drug effects by loading a certain amount or more of the drug into the carrier.

[0012] Furthermore, another object of the present invention is to effectively deliver a drug in a target area irradiated with ultrasonic energy by making the drug show high responsiveness to ultrasonic energy.

[0013] Furthermore, another object of the present invention is to enable concentrated delivery of drugs to a target area by preventing the natural release of drugs loaded in ultrasound-responsive drug carriers.

[0014] Furthermore, another object of the present invention is to load a certain amount or more of a hydrophilic drug into an ultrasound-responsive drug carrier by increasing the solubility of the hydrophilic drug in oil.

[0015] Technical means for solving technical problems

[0016] The features of the present invention are used to achieve the above-mentioned purpose of the present invention and the characteristic effects of the present invention described later, and its structure is as follows.

[0017] According to one embodiment of the present invention, a method for generating an ultrasound-responsive drug carrier for drug delivery is provided, which comprises: (a) obtaining a drug-ion conjugate using an acidic compound and the drug; and (b) generating the ultrasound-responsive drug carrier using the drug-ion conjugate, drug-carrying oil, inactive gas and phospholipids.

[0018] In the step (a), the drug-ion conjugate is obtained by adding the acidic compound to an aqueous drug solution in which the drug is dissolved to generate a drug-ion conjugate precipitate, and then washing and drying the drug-ion conjugate precipitate under reduced pressure.

[0019] In the step (a), after adding the sodium bicarbonate aqueous solution to the drug aqueous solution, the acidic compound is added to the drug aqueous solution to generate the drug-ion conjugate precipitate.

[0020] In the step (b), the drug-ion conjugate carrier oil is obtained by dissolving the drug-ion conjugate in the drug carrier oil, and the ultrasound-responsive drug carrier is generated by using the drug-ion conjugate carrier oil, the inactive gas and the phospholipid.

[0021] In the step (b), the drug-ion conjugate carrier oil is centrifuged to remove the insoluble drug-ion conjugate that is not dissolved in the drug-ion conjugate carrier oil, thereby obtaining the drug-ion conjugate carrier oil.

[0022] The drug is a hydrophilic drug.

[0023] The drug includes at least a part of anthracycline anticancer agents, metabolic antagonist anticancer agents and hypomethylation agonist anticancer agents.

[0024] The anthracycline anticancer agents include at least a part of daunorubicin, doxorubicin, mitoxantrone, epirubicin and carmichaline, the metabolic antagonist anticancer agents include cytarabine, and the hypomethylation agonist anticancer agents include at least a part of azacitidine and decitabine.

[0025] In the step (a), the drug includes an amino group (NH2), and in an aqueous drug solution in which the drug is dissolved, NH3+ is formed from the amino group of the drug by protonation, and after an acidic compound is added thereto, COO- is formed from the carboxyl group of the acidic compound by deprotonation, thereby obtaining the drug-ion conjugate through ionic bonding between the drug and the acidic compound.

[0026] The acidic compound includes at least a portion of nonanoic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, palmitoleic acid, stearic acid, oleic acid, linoleic acid, α-linoleic acid, eleostearic acid, β-linoleic acid, γ-linoleic acid, arachidonic acid, eicosapentaenoic acid, docosenoic acid, docosatetraenoic acid, docosapentaenoic acid, docosahexaenoic acid and nervonic acid.

[0027] The inert gas includes at least a portion of perfluoromethane, perfluoroethane, perfluoropropane, perfluorobutane, perfluoropentane, perfluorohexane, perfluoroheptane, perfluorooctane, decafluoropentane, perfluoro(2-methyl-3-pentanone), perfluorotributylamine, perfluoro-15-crown-5 ether, perfluoro-1,3-dimethylcyclohexane, perfluoromethylcyclopentane, perfluorodecalin, perfluoromethyldecalin, perfluoroperhydrobenzyltetralin, PERFECTA, and sulfur hexafluoride.

[0028] According to another embodiment of the present invention, there is provided an ultrasound-responsive drug carrier for drug delivery, which includes: a drug-ion conjugate obtained by an acidic compound and the drug; a drug-carrying oil for loading the drug-ion conjugate; an inactive gas; and a shell including phospholipids.

[0029] The ultrasound-responsive drug carrier is characterized in that: the drug-ion conjugate is obtained by adding the acidic compound to an aqueous drug solution in which the drug is dissolved to generate a drug-ion conjugate precipitate, and then washing and drying the drug-ion conjugate precipitate under reduced pressure.

[0030] After adding the sodium bicarbonate aqueous solution to the drug aqueous solution, the acidic compound is added to the drug aqueous solution to generate the drug-ion conjugate precipitate.

[0031] The ultrasound-responsive drug carrier is characterized by utilizing (i) a drug-ion conjugate carrier oil, which is obtained by dissolving the drug-ion conjugate in the drug carrier oil, (ii) the inactive gas, and (iii) the phospholipid to generate the ultrasound-responsive drug carrier.

[0032] The ultrasound-responsive drug carrier is characterized in that the insoluble drug-ion conjugates not dissolved in the drug-ion conjugate carrier oil are removed by centrifuging the drug-ion conjugate carrier oil dissolved in the drug-ion conjugate, thereby obtaining the drug-ion conjugate carrier oil.

[0033] The drug is a hydrophilic drug.

[0034] The drug includes at least a part of anthracycline anticancer agents, metabolic antagonist anticancer agents and hypomethylation agonist anticancer agents.

[0035] The anthracycline anticancer agents include at least a part of daunorubicin, doxorubicin, mitoxantrone, epirubicin and carmichaline, the metabolic antagonist anticancer agents include cytarabine, and the hypomethylation agonist anticancer agents include at least a part of azacitidine and decitabine.

[0036] The drug includes an amino group (NH2).

[0037] The size of the ultrasound-responsive drug carrier is 100 nm to 2 um.

[0038] The acidic compound includes at least a portion of nonanoic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, palmitoleic acid, stearic acid, oleic acid, linoleic acid, α-linoleic acid, eleostearic acid, β-linoleic acid, γ-linoleic acid, arachidonic acid, eicosapentaenoic acid, docosenoic acid, docosatetraenoic acid, docosapentaenoic acid, docosahexaenoic acid and nervonic acid.

[0039] The inert gas includes at least a portion of perfluoromethane, perfluoroethane, perfluoropropane, perfluorobutane, perfluoropentane, perfluorohexane, perfluoroheptane, perfluorooctane, decafluoropentane, perfluoro(2-methyl-3-pentanone), perfluorotributylamine, perfluoro-15-crown-5 ether, perfluoro-1,3-dimethylcyclohexane, perfluoromethylcyclopentane, perfluorodecalin, perfluoromethyldecalin, perfluoroperhydrobenzyltetralin, PERFECTA, and sulfur hexafluoride.

[0040] Effects of the Invention

[0041] The present invention protects the drug from the influence of the external environment by loading the drug into the ultrasound responsive drug carrier.

[0042] In addition, the present invention enables the ultrasound-responsive drug carrier to exhibit significant drug effects by loading a certain amount or more of the drug into the ultrasound-responsive drug carrier.

[0043] Furthermore, the present invention enables efficient delivery of a drug in a target area irradiated with ultrasonic energy by making the drug show high responsiveness to ultrasonic energy.

[0044] Furthermore, the present invention enables concentrated delivery of drugs to a target area by preventing the natural release of drugs loaded in the ultrasound-responsive drug carrier.

[0045] Furthermore, the present invention enables a certain amount or more of hydrophilic drugs to be loaded into the ultrasound-responsive drug carrier by increasing the solubility of the hydrophilic drugs in oil. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The following drawings used to describe embodiments of the present invention are only part of the embodiments of the present invention, and technicians in the field to which the present invention belongs (hereinafter referred to as "technicians") can obtain other drawings based on these drawings without performing any creative work.

[0047] Figure 1 An ultrasound-responsive drug carrier according to an embodiment of the present invention is schematically shown.

[0048] Figure 2 The schematic diagram shows a process for generating a drug-ion conjugate for generating an ultrasound-responsive drug carrier according to an embodiment of the present invention.

[0049] Figure 3a to Figure 3d The result of observing the ultrasound-responsive drug carrier structure according to an embodiment of the present invention is schematically shown.

[0050] Figure 4 The drug release rate when the ultrasound-responsive drug carrier is loaded with drugs and the drug release rate when the ultrasound-responsive drug carrier is not loaded with drugs according to one embodiment of the present invention are schematically shown.

[0051] Figure 5a to Figure 5e The result of irradiating ultrasound to an ultrasound-responsive drug carrier according to an embodiment of the present invention is schematically shown.

[0052] Figure 6 An application example of an ultrasound-responsive drug carrier according to an embodiment of the present invention is schematically shown. DETAILED DESCRIPTION

[0053] The following detailed description of the present invention refers to the accompanying drawings, which schematically illustrate specific embodiments in which the present invention can be implemented to illustrate the purpose, technical solutions and advantages of the present invention. These embodiments are described in sufficient detail to enable ordinary technicians to implement the present invention.

[0054] In addition, throughout the detailed description and claims of the present invention, the word "comprise" and its modifications are not intended to exclude other technical features, additions, constituent elements or steps. For those skilled in the art, some other purposes, advantages and characteristics of the present invention are obvious from this description, while others are obvious from the embodiments of the present invention. The following examples and drawings are exemplary and are not intended to limit the present invention.

[0055] The present invention includes any realizable combination of the embodiments in this specification. It should be understood that the various embodiments of the present invention are different but not necessarily mutually exclusive. For example, without exceeding the technical concept and scope of the present invention, the specific shapes, structures and characteristics described in this specification can be realized by other embodiments. In addition, it should be understood that without exceeding the technical concept and scope of the present invention, the position or configuration of each constituent element in each disclosed embodiment can be changed. Therefore, the detailed description described below does not have a limiting meaning, and as long as it can be properly described, the scope of the present invention is limited only by all scopes equivalent to those described in its claims and the attached claims. Similar figure marks in the drawings refer to the same or similar functions in many aspects.

[0056] In order to enable those skilled in the art to easily implement the present invention, preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0057] Figure 1 An ultrasound-responsive drug carrier 1000 for drug delivery according to an embodiment of the present invention is schematically shown.

[0058] See also Figure 1 In an ultrasound-responsive drug carrier 1000 according to an embodiment of the present invention, its outer surface may form a shell 100 containing phospholipids, and the interior includes a drug-carrying oil 300 loaded with an inactive gas 200 and a drug-ion conjugate.

[0059] For reference, the ultrasound-responsive drug carrier 1000 according to an embodiment of the present invention may be an ultrasound-responsive microbubble having a high responsiveness to ultrasound, but is not limited thereto.

[0060] At this time, the drug may be a hydrophilic drug, wherein the hydrophilic drug may refer to a drug that is only soluble in water and completely insoluble in oil, but is not limited thereto, and may also include a drug that is slightly soluble in oil but more soluble in water.

[0061] For example, the drug may include at least a portion of anthracycline anticancer agents, metabolic antagonist anticancer agents, and hypomethylating agonist anticancer agents.

[0062] Among them, anthracycline anticancer agents may include at least a part of daunorubicin, doxorubicin, mitoxantrone, epirubicin and carmichaline, metabolic antagonist anticancer agents may include cytarabine, and hypomethylating agonist anticancer agents may include at least a part of azacitidine and decitabine.

[0063] For another example, the drug as a hydrophobic drug may include bendamustine, busulfan, carmustine, chlorambucil, cyclophosphamide, dacarbazine, ifosfamide, melphalan, procarbazine, streptozocin, temozolomide, asparaginase, capecitabine, cytarabine, 5-fluorouracil, fludarabine, gemcitabine, methotrexate, pemetrexed, raltitrexed, actinomycin-D, bleomycin, daunorubicin, epirubicin, idarubicin, mitomycin, mitoxantrone, etoposide , docetaxel, irinotecan, paclitaxel, topotecan, vinblastine, vincristine, vinorelbine, carboplatin, cisplatin, oxaliplatin, alemtuzumab, BCG, bevacizumab, cetuximab, denosumab, erlotinib, gefitinib, imatinib, interferon, ipilimumab, lapatinib, panitumumab, rituximab, sunitinib, sorafenib, temsirolimus, trastuzumab, clodronate, ibandronate, pamidronate and zoledronic acid.

[0064] In addition, drug-ion conjugates can be obtained using acidic compounds and drugs.

[0065] For example, a drug-ion conjugate precipitate can be generated by adding an acidic compound to an aqueous drug solution in which the drug is dissolved. In addition, a drug-ion conjugate precipitate can be obtained by washing and drying the drug-ion conjugate precipitate under reduced pressure.

[0066] At this time, in order to correct the pH, after adding a sodium bicarbonate aqueous solution to the aqueous drug solution, an acidic compound may be added to the aqueous drug solution to generate a drug-ion conjugate precipitate.

[0067] At this time, the acidic compound used to generate the ultrasound-responsive drug carrier 1000 according to an embodiment of the present invention may include fatty acids, for example, may include at least a portion of nonanoic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, palmitoleic acid, stearic acid, oleic acid, linoleic acid, α-linoleic acid, eleostearic acid, β-linoleic acid, γ-linoleic acid, arachidonic acid, eicosapentaenoic acid, docosenoic acid, docosatetraenoic acid, docosapentaenoic acid, docosahexaenoic acid and neuraminic acid.

[0068] In addition, the drug contained in the ultrasound-responsive drug carrier 1000 according to an embodiment of the present invention may be a drug containing an amino group (NH2). For example, after protonation and deprotonation, the amino group (NH2) of the drug and the carboxyl group (COOH) of the acidic compound can form a drug-ion conjugate through ionic bonding between the drug and the acidic compound.

[0069] See below Figure 2 The process of forming a drug-ion conjugate is described as an example. As a reference, for ease of description, Figure 2 An example in which a doxorubicin ion conjugate is obtained as a drug-ion conjugate by doxorubicin, sodium bicarbonate, and oleic acid is shown, but the present invention is not limited thereto.

[0070] See also Figure 2 When an aqueous sodium bicarbonate solution is added to an aqueous doxorubicin solution, protonation occurs, thereby forming NH3+ from the amino group (NH2) of doxorubicin. If an acidic compound (e.g., oleic acid) is added thereto, deprotonation occurs, thereby forming COO- from the carboxyl group (COOH) of oleic acid, thereby obtaining a doxorubicin ion conjugate as a drug-ion conjugate through ionic bonding of doxorubicin and oleic acid.

[0071] In addition, the ultrasound-responsive drug carrier 1000 can be generated using drug-ion conjugates, drug-carrying oils, inactive gases, and phospholipids.

[0072] For reference, the inactive gas used to generate the ultrasound-responsive drug carrier 1000 according to an embodiment of the present invention may include perfluorocarbon gases (for example, perfluoromethane, perfluoroethane, perfluoropropane, perfluorobutane, perfluoropentane, perfluorohexane, perfluoroheptane, perfluorooctane, decafluoropentane, perfluoro(2-methyl-3-pentanone), perfluorotributylamine, perfluoro-15-crown-5 ether, perfluoro-1,3-dimethylcyclohexane, perfluoromethylcyclopentane, perfluorodecalin, perfluoromethyldecalin, perfluoroperhydrobenzyltetralin, PERFECTA, etc.), sulfur hexafluoride, and at least a portion of the air. For reference, the inactive gas included in the ultrasound-responsive drug carrier 1000 may be in liquid form, but is not limited to this, and may also be in gaseous form.

[0073] In addition, the drug-carrying oil included in the ultrasound-responsive drug carrier 1000 according to an embodiment of the present invention may include at least a portion of almond oil, apricot oil, avocado oil, rapeseed oil, castor oil, coconut oil, cocoa butter, corn oil, cottonseed oil, linseed oil, medium-chain triglyceride (MCT) oil, palm oil, soybean oil and sunflower oil.

[0074] In addition, the phospholipids contained in the shell formed on the outer surface of the ultrasound-responsive drug carrier 1000 according to an embodiment of the present invention may include at least a portion of DPPC, DPPA, DSPE-mPEG-2000 and cholesterol. However, the present invention is not limited thereto, and the phospholipids contained in the shell formed on the outer surface of the ultrasound-responsive drug carrier 1000 according to an embodiment of the present invention may include at least a portion of phosphatidylcholine substances (HSPC, DEPC, DOPC and DMPC, etc.), DMPA-NA, DPPA-Na, DOPA-Na, DSPE, DSPE-mPEG, DSPE-mPEG-2000-Na, DSPE-mPEG-5000-Na, DSPE-Maleimide PEG-2000-Na.

[0075] For example, a drug-ion conjugate carrier oil can be obtained by dissolving a drug-ion conjugate in a drug carrier oil, and the ultrasound-responsive drug carrier 1000 can be generated using the drug-ion conjugate carrier oil, an inactive gas, and a phospholipid.

[0076] At this time, the drug-ion conjugate-carrying oil in which the drug-ion conjugate is dissolved can be centrifuged to remove the insoluble drug-ion conjugate that is not dissolved in the drug-carrying oil, thereby obtaining the drug-ion conjugate-carrying oil.

[0077] For reference, the insoluble drug-ion conjugate may refer to a portion of the drug-ion conjugate that is no longer dissolved in the saturated state of the drug carrier oil when the drug-ion conjugate is excessively put into the drug carrier oil in an amount greater than its solubility in the drug carrier oil.

[0078] Furthermore, the ultrasound-responsive drug carrier 1000 can be generated by mechanically mixing a mixture comprising a drug-ion conjugate carrier oil, an inactive gas, and a phospholipid.

[0079] The diameter of the ultrasound-responsive drug carrier 1000 according to one embodiment of the present invention generated by the above process may be 100 nm to 2 um. However, the present invention is not limited thereto, and the size of the ultrasound-responsive drug carrier 1000 may be determined by changing the rpm value of mechanical mixing or selecting oils of different viscosities.

[0080] In addition, see Figure 1 It can be confirmed that the shell 100 formed outside the ultrasound-responsive drug carrier 1000 has a phospholipid monolayer shape.

[0081] For reference, the head of a phospholipid is hydrophilic and the tail is hydrophobic, so Figure 1 The interior of the ultrasound-responsive drug carrier shown to include a shell formed as a single layer is hydrophobic.

[0082] Therefore, the prior art is unable to load hydrophilic drugs into ultrasound-responsive drug carriers comprising an outer shell formed of a phospholipid monolayer.

[0083] For example, doxorubicin is a hydrophilic drug with a solubility in water greater than 10 mg / mL and a solubility in oil less than 100 ug / mL. Even if a mixture containing doxorubicin, an inactive gas, and a phospholipid is mechanically mixed to generate microbubbles having an outer shell formed by a phospholipid monolayer, doxorubicin is not present inside the microbubbles generated in this way, or only a very small amount of doxorubicin is present.

[0084] In contrast, according to one embodiment of the present invention, a hydrophilic drug is effectively dissolved in a drug-carrying oil by forming an ion conjugate, thereby generating a drug-ion conjugate-carrying oil. The drug-ion conjugate-carrying oil generated in this way has the advantage of being able to be loaded in large quantities inside a shell formed of a phospholipid monolayer.

[0085] For reference, taking the doxorubicin ion conjugate as an example, its solubility in water is greatly reduced (eg, 10 ug / mL or lower) compared to the solubility of doxorubicin, whereas its solubility in oil is greatly increased (eg, 10 mg / mL or more).

[0086] Furthermore, according to another embodiment of the present invention, after dissolving the hydrophobic drug in the oil, the oil in which the hydrophobic drug is dissolved can be loaded into the ultrasound-responsive drug carrier.

[0087] If the hydrophobic drug is loaded into the ultrasound-responsive drug carrier without dissolving the hydrophobic drug in oil, the problem of excessive release of the hydrophobic drug loaded in the ultrasound-responsive drug carrier may occur before the ultrasound-responsive drug carrier is irradiated with ultrasound.

[0088] Therefore, according to another embodiment of the present invention, after dissolving the sleep-wake drug in the oil, the vial mixed with the oil (in which the hydrophobic drug is dissolved), the inactive gas and the phospholipid aqueous solution is mechanically mixed, thereby generating an ultrasound-responsive drug carrier.

[0089] In addition, the following is a process for generating an ultrasound-responsive drug carrier 1000 according to an embodiment of the present invention by using specific drugs (e.g., doxorubicin, etc.), specific acidic compounds (e.g., nonanoic acid, palmitic acid, oleic acid, etc.), specific drug carrier oils (e.g., MCT oil, soybean oil, etc.), specific inactive gases (e.g., perfluorohexane), and specific phospholipids (e.g., DPPC, DPPA, and cholesterol, etc.).

[0090] However, the generation process of the ultrasound responsive drug carrier 1000 described below is only an example to help understand the present invention, and the present invention is not limited to this. Those skilled in the art can easily understand without undue effort the method of generating the ultrasound responsive drug carrier 1000 according to the present invention by combining other drugs, other acidic compounds, other drug carrier oils, other inactive gases, and other phospholipids as described above.

[0091] For reference, the ultrasound-responsive drug carrier described below may be ultrasound-responsive microbubbles having a high responsiveness to ultrasound waves, but is not limited thereto.

[0092] For example, 50 mg of doxorubicin hydrochloride can be placed in a 50 mL glass vial and then 10 mL of distilled water can be added to produce an aqueous doxorubicin solution with a concentration of 5 mg / mL.

[0093] Alternatively, 2 mL of a 50 mg / mL sodium bicarbonate (chloride) aqueous solution may be slowly added to a 5 mg / mL doxorubicin aqueous solution and stirred. pH correction may be performed by the above process.

[0094] In addition, 0.5 g of an acidic compound (e.g., any one of nonanoic acid, palmitic acid, and oleic acid) is diluted in 10 mL of ethanol, and the diluted acidic compound is slowly added to the doxorubicin aqueous solution and stirred at room temperature for 30 minutes, thereby forming a precipitate (i.e., a doxorubicin ion conjugate precipitate as a drug-ion conjugate precipitate).

[0095] Furthermore, the doxorubicin ion conjugate precipitate is washed with distilled water and dried under reduced pressure at room temperature, thereby obtaining the doxorubicin ion conjugate.

[0096] Furthermore, after 50 mg of the doxorubicin ion conjugate is dispersed in 10 mL of oil (eg, MCT oil or soybean oil), the doxorubicin ion conjugate is dissolved using an ultrasonic cleaner at 40° C. for 1 hour.

[0097] Furthermore, the oil in which the doxorubicin ion conjugate is dissolved (drug-ion conjugate carrier oil) is centrifuged using a centrifuge, thereby removing the doxorubicin ion conjugate that is not dissolved in the oil (ie, insoluble drug-ion conjugate).

[0098] In addition, (i) 0.2 g of dipalmitoylphosphatidylcholine (DPPC, 1,2-Dipalmitoyl-sn-glycerol-3-phosphocholine), (ii) 0.02 mg of diphenylphosphoryl azide (DPPA, diphenylphosphoryl azide), and (iii) 0.035 mg of cholesterol are dispersed in 30 mL of propylene glycol and then vortexed and sonicated (for example, using a bath sonicator at 40°C for about 1 hour) to achieve dissolution.

[0099] Furthermore, by adding 70 mL of distilled water to the phospholipid aqueous solution in which DPPC, DPPA and cholesterol are dissolved, a phospholipid aqueous solution for preparing the ultrasound-responsive drug carrier 1000 can be obtained. For reference, the refrigerated temperature of the phospholipid aqueous solution can be 4°C.

[0100] Alternatively, (i) 1.8 mL of an aqueous phospholipid solution, (ii) 0.1 mL of an oil in which a doxorubicin ion conjugate is dissolved, and (iii) 0.1 mL of perfluorohexane may be added in sequence to a 2 mL glass vial.

[0101] In addition, an emulsion (i.e., an ultrasound-responsive drug carrier) can be generated by mechanically mixing (i) a phospholipid aqueous solution, (ii) an oil in which a doxorubicin ion conjugate is dissolved, and (iii) perfluorohexane placed in a glass vial. For reference, the ultrasound-responsive drug carrier 1000 can be generated by mechanically mixing as follows: (i) when using a vial mixer, mechanical mixing at 4500 rpm for 45 seconds, and (ii) when using a homogenizer, mechanical mixing at 35000 rpm for 5 minutes.

[0102] In addition, see Figure 3a to Figure 3d The imaging result of the ultrasound-responsive drug carrier 1000 generated by the preparation method according to an embodiment of the present invention and the size of the ultrasound-responsive drug carrier 1000 are confirmed.

[0103] First, see Figure 3a and Figure 3b It can be confirmed that the interior of the ultrasound responsive drug carrier 1000 generated by the preparation method according to an embodiment of the present invention is divided into a crescent shape.

[0104] In particular, see Figure 3b, it can be confirmed that the interior of the ultrasound-responsive drug carrier 1000 is divided into (i) a space imaged green, which is occupied by the drug-carrying oil in which the doxorubicin ion conjugate is dissolved, and (ii) a space imaged black, which is occupied by an inactive gas.

[0105] In addition, through Figure 3a and Figure 3b It can be confirmed that the inert gas is fixed at a specific position inside the ultrasound responsive drug carrier 1000. If the inert gas is not fixed at a specific position inside the ultrasound responsive drug carrier, but moves freely inside the ultrasound responsive drug carrier, it may not show a crescent shape (such as Figure 3a and Figure 3d The partitioning style is shown in Figure 1.

[0106] Specifically, when the inactive gas is fixed at a specific position inside the ultrasonic responsive drug carrier, the arrangement direction of the ultrasonic responsive drug carrier can be determined according to the weight of the inactive gas. Therefore, irradiating ultrasonic waves according to the arrangement direction of the ultrasonic responsive drug carrier can exert a more effective cavitation effect.

[0107] also, Figure 3c The imaging results of the cross section of the ultrasound-responsive drug carrier 1000 according to an embodiment of the present invention are shown at various depths.

[0108] also, Figure 3d FIG. 2 shows a diameter distribution diagram (intensity) of an ultrasound-responsive drug carrier 1000 according to an embodiment of the present invention. Figure 3d It can be seen that the diameter of the ultrasound-responsive drug carrier 1000 according to an embodiment of the present invention shows a distribution of about 100 nm to 2 μm, with an average diameter of 771.1 nm and a dispersion of 0.395. That is, it can be confirmed that no large ultrasound-responsive drug carriers greater than or equal to 8 μm (a size that may cause complications in blood vessels) are generated.

[0109] also, Figure 4 Schematically showing (i) the drug release rate when ultrasound is not irradiated on the ultrasound-responsive drug carrier 1000 according to an embodiment of the present invention, (ii) the drug release rate of MCT oil in which doxorubicin ion conjugates are dissolved, and (iii) the drug release rate of doxorubicin not dissolved in MCT oil.

[0110] For reference, Figure 4The results of detecting the drug release rate of each example are shown after (i) an ultrasound-responsive drug carrier according to an embodiment of the present invention (i.e., an ultrasound-responsive drug carrier internally loaded with a doxorubicin ion conjugate), (ii) MCT oil in which a doxorubicin ion conjugate is dissolved (i.e., not in a state of being loaded with the ultrasound-responsive drug carrier), and (iii) doxorubicin not dissolved in MCT oil (i.e., not in a state of being loaded with the ultrasound-responsive drug carrier), when each membrane tube is immersed in a medium (which has properties similar to those in the in vivo environment) and then placed.

[0111] See also Figure 4 , taking doxorubicin not dissolved in MCT oil as an example, it can be seen that nearly 30% of the drug was released from the membrane tube into the medium at 1 minute due to osmotic pressure, and 60% or more of the drug was released after 5 minutes.

[0112] In addition, taking MCT oil dissolved with doxorubicin ion conjugate as an example, it can be seen that its drug release rate is lower than that of doxorubicin not dissolved in MCT oil, but more drug is released than when doxorubicin ion conjugate is loaded in ultrasound-responsive drug carrier.

[0113] As described above, when the drug release rate is high, even if the drug is injected into a subject, it is released from blood vessels to surrounding tissues before reaching the target site due to osmotic pressure, etc., making it difficult to effectively deliver the drug to the desired site at the desired time point.

[0114] In contrast, taking the ultrasound-responsive drug carrier 1000 according to an embodiment of the present invention as an example, the drug release rate it exhibits is significantly lower than the above two examples. This means that when the ultrasound-responsive drug carrier 1000 according to an embodiment of the present invention is injected into a subject, the amount of drug lost before reaching the target site can be minimized, and the drug can be effectively delivered to the desired site at the desired time point.

[0115] also, Figure 5a to Figure 5e The result of irradiating ultrasound on the ultrasound-responsive drug carrier 1000 is schematically shown to confirm the responsiveness of the ultrasound-responsive drug carrier 1000 to ultrasound energy according to an embodiment of the present invention.

[0116] First, see Figure 5a It can be confirmed that when the ultrasound responsive drug carrier 1000 according to an embodiment of the present invention is applied to a silicone tube, ultrasound is applied to the ultrasound responsive drug carrier 1000 using an ultrasound irradiation device (transducer), and its environment is photographed using an imaging device.

[0117] also, Figure 5b Shown by Figure 5a The imaging device shown captures the results of ultrasound-responsive drug carrier 1000. Figure 5b, it can be seen that the longer the ultrasonic irradiation time is, the darker the middle area in the four images (i.e., the area where the ultrasonic response drug carrier is located).

[0118] also, Figure 5c The image brightness of (i) the ultrasound-responsive drug carrier 1000 with ultrasound irradiation and (ii) the image brightness of the ultrasound-responsive drug carrier 1000 without ultrasound irradiation are shown. For reference, the ultrasound-responsive drug carrier 1000 according to an embodiment of the present invention exhibits high responsiveness to ultrasound energy, so when ultrasound is irradiated, the ultrasound-responsive drug carrier 1000 is destroyed by the cavitation effect, thereby releasing the drug. Figure 5c When the ultrasound-responsive drug carrier 1000 according to an embodiment of the present invention is irradiated with ultrasound (US), the image brightness is much lower than the image brightness when it is not irradiated with ultrasound. This confirms that the ultrasound-responsive drug carrier 1000 according to an embodiment of the present invention exhibits high responsiveness to ultrasound energy.

[0119] also, Figure 5d 1 is a picture of the ultrasound-responsive drug carrier 1000 taken before irradiating the ultrasound-responsive drug carrier 1000 with ultrasound. Figure 5e 100 is a picture of the ultrasound-responsive drug carrier 1000 taken after irradiating the ultrasound-responsive drug carrier 1000 with ultrasound.

[0120] See also Figure 5d and Figure 5e It can be seen that most of the ultrasound-responsive drug carriers 1000 are destroyed after being irradiated with ultrasound, which confirms that the ultrasound-responsive drug carrier 1000 according to an embodiment of the present invention exhibits a high responsiveness to ultrasound energy.

[0121] In addition, see Figure 6 A method for effectively delivering drugs using the ultrasound-responsive drug carrier 1000 according to an embodiment of the present invention is described in detail.

[0122] See also Figure 6 By injecting the ultrasound responsive drug carrier 1000 into a blood vessel and irradiating ultrasound to the target site, the doxorubicin contained in the ultrasound responsive drug carrier 1000 can be effectively delivered to the target site, wherein the ultrasound responsive drug carrier 1000 is generated by the following process: after mixing (i) oil in which doxorubicin ion conjugate is dissolved, (ii) inactive gas, and (iii) phospholipid aqueous solution, mechanical mixing is performed at 4500 rpm for 45 seconds using a roller bottle machine.

[0123] The present invention is described above through specific matters such as specific constituent elements and limited embodiments and drawings, but this is only to help a comprehensive understanding of the present invention. The present invention is not limited thereto, and technicians in the field of the present invention can make various modifications and changes based on the above description.

[0124] Therefore, the technical concept of the present invention should not be limited to the embodiments described above, and the claims and modifications equivalent or equivalent to the claims all belong to the technical concept scope of the present invention.

Claims

1. A method for producing an ultrasound-responsive drug carrier for drug delivery, comprising: (a) obtaining a drug-ion conjugate using an acidic compound and the drug; as well as (b) using the drug-ion conjugate, drug-carrying oil, inactive gas and phospholipid to generate the ultrasound-responsive drug carrier.

2. The method according to claim 1, characterized in that: In the step (a), The drug-ion conjugate is obtained by adding the acidic compound to an aqueous drug solution in which the drug is dissolved to generate a drug-ion conjugate precipitate, and then washing and drying the drug-ion conjugate precipitate under reduced pressure.

3. The method according to claim 2, characterized in that: In the step (a), After adding the sodium bicarbonate aqueous solution to the drug aqueous solution, the acidic compound is added to the drug aqueous solution to generate the drug-ion conjugate precipitate.

4. The method according to claim 1, characterized in that: In the step (b), The drug-ion conjugate carrier oil is obtained by dissolving the drug-ion conjugate in the drug carrier oil, and the ultrasound-responsive drug carrier is generated by using the drug-ion conjugate carrier oil, the inactive gas and the phospholipid.

5. The method according to claim 4, characterized in that: In the step (b), The drug-ion conjugate carrier oil is centrifuged to remove the insoluble drug-ion conjugate that is not dissolved in the drug-ion conjugate carrier oil, thereby obtaining the drug-ion conjugate carrier oil.

6. The method according to claim 1, characterized in that: The drug is a hydrophilic drug.

7. The method according to claim 6, characterized in that: The drug includes at least a part of anthracycline anticancer agents, metabolic antagonist anticancer agents and hypomethylation agonist anticancer agents.

8. The method according to claim 7, characterized in that: The anthracycline anticancer agent includes at least a part of daunorubicin, doxorubicin, mitoxantrone, epirubicin and carmichaline, The metabolic antagonist anticancer agents include cytarabine, The hypomethylating agonist anticancer agent includes at least a portion of azacitidine and decitabine.

9. The method according to claim 1, characterized in that: In the step (a), The drug includes an amino group (NH2), In the aqueous drug solution in which the drug is dissolved, NH3 is formed from the amino group of the drug by protonation. + , and after adding an acidic compound thereto, COO is formed from the carboxyl group of the acidic compound by deprotonation. - , thereby obtaining the drug-ion conjugate through ionic bonding of the drug and the acidic compound.

10. The method according to claim 1, characterized in that: The acidic compound includes at least a portion of nonanoic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, palmitoleic acid, stearic acid, oleic acid, linoleic acid, α-linoleic acid, eleostearic acid, β-linoleic acid, γ-linoleic acid, arachidonic acid, eicosapentaenoic acid, docosenoic acid, docosatetraenoic acid, docosapentaenoic acid, docosahexaenoic acid and nervonic acid.

11. The method according to claim 1, characterized in that: The inert gas includes at least a portion of perfluoromethane, perfluoroethane, perfluoropropane, perfluorobutane, perfluoropentane, perfluorohexane, perfluoroheptane, perfluorooctane, decafluoropentane, perfluoro(2-methyl-3-pentanone), perfluorotributylamine, perfluoro-15-crown-5 ether, perfluoro-1,3-dimethylcyclohexane, perfluoromethylcyclopentane, perfluorodecalin, perfluoromethyldecalin, perfluoroperhydrobenzyltetralin, PERFECTA, and sulfur hexafluoride.

12. An ultrasound-responsive drug carrier for delivering drugs, comprising: a drug-ion conjugate obtained by an acidic compound and the drug; A drug-carrying oil, which is used to load the drug-ion conjugate; Inert gases; as well as An outer shell comprising phospholipids.

13. The ultrasound-responsive drug carrier according to claim 12, characterized in that: The drug-ion conjugate is obtained by adding the acidic compound to an aqueous drug solution in which the drug is dissolved to generate a drug-ion conjugate precipitate, and then washing and drying the drug-ion conjugate precipitate under reduced pressure.

14. The ultrasound-responsive drug carrier according to claim 13, characterized in that: After adding the sodium bicarbonate aqueous solution to the drug aqueous solution, the acidic compound is added to the drug aqueous solution to generate the drug-ion conjugate precipitate.

15. The ultrasound-responsive drug carrier according to claim 12, characterized in that: The ultrasound-responsive drug carrier is produced using (i) a drug-ion conjugate carrier oil obtained by dissolving the drug-ion conjugate in the drug carrier oil, (ii) the inert gas, and (iii) the phospholipid.

16. The ultrasound-responsive drug carrier according to claim 15, characterized in that: The drug-ion conjugate carrier oil is centrifuged to remove the insoluble drug-ion conjugate that is not dissolved in the drug-ion conjugate carrier oil, thereby obtaining the drug-ion conjugate carrier oil.

17. The ultrasound-responsive drug carrier according to claim 12, characterized in that: The drug is a hydrophilic drug.

18. The ultrasound-responsive drug carrier according to claim 17, characterized in that: The drug includes at least a part of anthracycline anticancer agents, metabolic antagonist anticancer agents and hypomethylation agonist anticancer agents.

19. The ultrasound-responsive drug carrier according to claim 18, characterized in that: The anthracycline anticancer agent includes at least a part of daunorubicin, doxorubicin, mitoxantrone, epirubicin and carmichaline, The metabolic antagonist anticancer agents include cytarabine, The hypomethylating agonist anticancer agent includes at least a portion of azacitidine and decitabine.

20. The ultrasound-responsive drug carrier according to claim 12, characterized in that: The drug includes an amino group (NH2).

21. The ultrasound-responsive drug carrier according to claim 12, characterized in that: The size of the ultrasound-responsive drug carrier is 100 nm to 2 um.

22. The ultrasound-responsive drug carrier according to claim 12, characterized in that: The acidic compound includes at least a portion of nonanoic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, palmitoleic acid, stearic acid, oleic acid, linoleic acid, α-linoleic acid, eleostearic acid, β-linoleic acid, γ-linoleic acid, arachidonic acid, eicosapentaenoic acid, docosenoic acid, docosatetraenoic acid, docosapentaenoic acid, docosahexaenoic acid and nervonic acid.

23. The ultrasound-responsive drug carrier according to claim 12, characterized in that: The inert gas includes at least a portion of perfluoromethane, perfluoroethane, perfluoropropane, perfluorobutane, perfluoropentane, perfluorohexane, perfluoroheptane, perfluorooctane, decafluoropentane, perfluoro(2-methyl-3-pentanone), perfluorotributylamine, perfluoro-15-crown-5 ether, perfluoro-1,3-dimethylcyclohexane, perfluoromethylcyclopentane, perfluorodecalin, perfluoromethyldecalin, perfluoroperhydrobenzyltetralin, PERFECTA, and sulfur hexafluoride.

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