KR102046355B1 - Liposomal formulation of sustained-release physostigmine for subcutaneous injection and preparation method thereof - Google Patents

Abstract

The present invention relates to a subcutaneous injectable liposome preparation including physostigmine which can prevent poisoning enteric by a neurological agent such as sarin gas, and a preparation method thereof, as compared with the administration of the conventional physostigmine solution, When administered, it is possible to prolong the release of the drug and to prolong the circulation time in the blood to prolong the prophylactic effect on the neurological agent and to improve safety by minimizing the side effects caused by high blood concentrations.

Description

Liposomal formulation of sustained-release physostigmine for subcutaneous injection and preparation method according to subcutaneous physostigmine

The present invention is a subcutaneous injection liposome preparation and a method for preparing the same, which sustains the rapid release of physostigmine for a long time and prolongs blood circulation, and minimizes side effects due to high blood concentration due to the rapid absorption of the existing solution formulation. It is about.

Chemical agents that can be used as biochemical weapons in wartime include neurotoxic agents that cause neurotoxicity, blisters that cause skin burns, blood agents that suppress the respiration of blood from the blood, asphyxiation agents that cause respiratory damage and pulmonary edema, Gas and the like. Neurological agents are more toxic and lethal than other chemical agents, and above all, there is a risk that symptoms of poisoning develop very quickly. Examples of such toxic substances include sarin, mannose, starch, cyclohexyl sarin, and insecticides such as parathion and malachion, which belong to organophosphorus compounds, which can be easily vaporized and easily absorbed through the skin or the respiratory tract. Can be.

The key mechanism by which this neurological agent causes poisoning in the body is to irreversibly induce strong cholinergic neuronal activity. Normally, acetylcholine secreted from the synapse should be degraded by cholinesterase after signal transduction. Since the infiltration of organophosphorus compounds inhibits this enzyme irreversibly, the cholinergic action caused by undegraded acetylcholine is excessive. To get up. This can lead to symptoms of intoxication, for example, excessive saliva, dilated pupils, convulsions, and asphyxiation due to respiratory muscle paralysis.

As an antidote to these neurological agents, atropine and pralidoxime are used as intramuscular injections in the current group. The first injection of atropine reverses the strong cholinergic action of neuronal agents, and the subsequent dose of pralidoxime separates the organophosphorus compound attached to the enzyme and reactivates the enzyme. Although both drugs can prevent symptoms of intoxication such as asphyxiation when exposed to neurological agents, they do not prevent exposure and addiction in advance, and brain damage caused by brain infiltration of neurological agents is also difficult to avoid.

In order to overcome the limitations, drugs of different mechanisms have been studied for the purpose of preventing neurotoxic intoxication, such as carbamate drugs such as physostigmine, pyridostigmine, rivastigmine, and galantamine, Or Alzheimer's agents such as donepezil. These drugs function similarly to nerve agents in that they increase cholinergic action, but unlike neuronal agents that irreversibly bind to cholinesterase, they reversibly inhibit the enzyme. By binding to the pre-cholinesterase in the body can be prevented from irreversibly binding to enzymes such as sarin gas. In the case of organophosphorus compound, which is a nerve agent, the binding force to the enzyme is very strong, but since it is rapidly lost in the body, if the preventive drug is maintained at a constant concentration in the body, the result can be prevented. In fact, the U.S. military is known to provide regular intake of pyridostigmine bromide for the purpose of preventing nerve gas. However, pyridostigmine has a disadvantage in that it is difficult to protect the brain because it cannot pass through the blood-brain barrier because it is a drug corresponding to a quaternary amine.

Physostigmine, a tertiary amine, is a drug that can prevent the action of nerve agents in the whole body, including the brain. Physostigmine can cross the blood-brain barrier and exhibit higher enzyme binding rates than other cholinesterase inhibitors, thus protecting the enzymes from neuronal agents more effectively. However, in case of physostigmine, since the half-life of the body is shorter than 1 hour after the administration, it has a limitation that it does not last long. In order to show an effective preventive action with physostigmine, it is important to keep the concentration of the drug at a certain level for a long time.

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United States Patent Application Publication No. US 2013/0309297

The present invention is to solve the above-mentioned problems of the prior art, an object of the present invention is to enable the encapsulation and sustained release of physostigmine and to extend the blood circulation during administration in the body due to the rapid loss of existing drugs and high blood concentration It is to provide a liposome preparation and a method for preparing the same that can improve the risk of toxicity.

However, the problem to be solved by the present invention is not limited to the above-mentioned problem, another task that is not mentioned will be clearly understood by those skilled in the art from the following description.

According to one embodiment of the invention, there is provided a subcutaneous injection preparation in which liposome particles comprising 1-5 parts by weight of a cholinesterase inhibitor drug, 50-80 parts by weight lipid and 20-80 parts by weight cholesterol are dispersed in water. .

According to one side, the cholinesterase inhibitor drug is selected from the group consisting of physostigmine, physostigmine salicylate, pyridostigmine, neostigmine, rivastigmine, galantamine, tacrine and donepezil It may be to include any one.

According to one side, the lipid is phosphatidylcholine derived from soy lecithin or egg yolk lecithin, cholesterol, polyethylene glycol-phosphatidylcholine, polyethylene glycol-tocopherol, stearylamine and one selected from the group consisting of stearyl acid Can be.

According to one side, the liposome particles may be dispersed in water at a concentration of 5 to 20 mg / ml.

According to one side, the cholinesterase inhibitor drug may be present in the form encapsulated in the liposome particles.

According to another embodiment of the present invention, preparing a solution comprising 50-80 parts by weight of lipid and 20-80 parts by weight of cholesterol; Evaporating the solution to form a lipid film; Hydrating the lipid film with an acidic buffer solution to prepare a liposome solution; Mixing a basic buffer solution with the liposome solution; And inserting a cholinesterase inhibitor drug into the liposome; Including, a method for producing a liposome preparation is provided.

According to one side, after the step of encapsulating in the liposome by the input of the cholinesterase inhibitor drug, using a semi-permeable membrane, dialysis in an excess of distilled water to obtain a purified liposome; may further include a.

According to one side, after the step of preparing the liposome solution, homogenizing the average particle size of the liposome to 50 to 200nm using an ultrasonic treatment or an extruder; It may further include.

According to one side, the acidic buffer solution may be any one selected from the group consisting of formic acid, citric acid, acetic acid, hydrochloric acid, phosphoric acid and phthalate acid.

According to one side, the basic buffer solution, may be any one selected from the group consisting of sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium carbonate, sodium hydrogen carbonate and sodium borate.

According to one side, the cholinesterase inhibitor drug is selected from the group consisting of physostigmine, physostigmine salicylate, pyridostigmine, neostigmine, rivastigmine, galantamine, tacrine and donepezil It may be to include any one.

According to one side, the lipid is phosphatidylcholine derived from soy lecithin or egg yolk lecithin, cholesterol, polyethylene glycol-phosphatidylcholine, polyethylene glycol-tocopherol, stearylamine and one selected from the group consisting of stearyl acid Can be.

In the liposome preparation of the present invention and a method for preparing the same, a hydrophilic drug such as physostigmine can be encapsulated in liposome, and the sustained release of the encapsulated drug is possible. That is, when the liposome preparation of the present invention is administered, the drug gradually reaches the highest blood concentration and is slowly absorbed, so that the blood concentration can be maintained longer, and the concentration is lower than that of the solution injection, thereby minimizing the symptoms of poisoning by the drug. can do.

Thus, the administration of the liposome preparation of the present invention can more effectively protect enzymes from neurological agents.

It is to be understood that the effects of the present invention are not limited to the above effects, and include all effects deduced from the configuration of the invention described in the detailed description or claims of the present invention.

1 is a graph showing the particle size distribution of liposomes according to an embodiment of the present invention.
2 is a graph showing the particle size distribution of liposomes according to another embodiment of the present invention.
3 is an electron micrograph of a liposome according to an embodiment of the present invention.
4 is an electron micrograph of a liposome according to another embodiment of the present invention.
5 is a graph showing the rate of drug release over time.
6 is a graph showing blood concentrations of drugs over time.
7 is a graph showing the inhibition rate of cholinesterase in blood over time.

Hereinafter, exemplary embodiments will be described in detail with reference to the accompanying drawings. Like reference numerals in the drawings denote like elements.

Various modifications may be made to the embodiments described below. The examples described below are not intended to be limited to the embodiments and should be understood to include all modifications, equivalents, and substitutes for them.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of examples. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as "comprise" or "have" are intended to indicate that there is a feature, number, step, action, component, part, or combination thereof described on the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

In addition, in the description with reference to the accompanying drawings, the same components regardless of reference numerals will be given the same reference numerals and redundant description thereof will be omitted. In the following description of the embodiment, when it is determined that the detailed description of the related known technology may unnecessarily obscure the gist of the embodiment, the detailed description thereof will be omitted.

Various formulation techniques can be applied to slow the absorption of drugs that are rapidly absorbed and to prolong the blood circulation of drugs with rapid loss of body, and one example is liposomes. Liposomes are preparations in the form of microparticles consisting of phospholipid bilayers, which have the advantage of encapsulating hydrophilic drugs as well as hydrophobic drugs. This can contribute to slowing the release of hydrophilic drugs that can be absorbed quickly. In addition, when these liposomes are stored at the topical site by subcutaneous administration or the like, prolonged release of the drug from the topical drug can extend the systemic absorption and blood circulation.

According to one embodiment of the invention, there is provided a subcutaneous injection preparation in which liposome particles comprising 1-5 parts by weight of a cholinesterase inhibitor drug, 50-80 parts by weight lipid and 20-80 parts by weight cholesterol are dispersed in water. .

According to one side, the cholinesterase inhibitor is any selected from the group consisting of physostigmine, physostigmine salicylate, pyridostigmine, neostigmine, rivastigmine, galantamine, tacrine and donepezil It may be to include one.

According to one side, the lipid is phosphatidylcholine derived from soy lecithin or egg yolk lecithin, cholesterol, polyethylene glycol-phosphatidylcholine, polyethylene glycol-tocopherol, stearylamine and one selected from the group consisting of stearyl acid Can be. Polyethyleneglycol-phosphatidylcholine, polyethyleneglycol-tocopherol, stearylamine, or stearyl acid may be derived from soy lecithin or egg yolk lecithin to change the properties of the liposomes themselves, the release pattern of the drug, the surface charge, or to improve drug stability. In addition to phosphatidylcholine and cholesterol can be added. In addition, in order to supplement the drug sustained release ability of the liposome itself, the lipid may be mixed with a polymer material. For example, when a liposome is prepared by mixing a polymer having hydrophilic polyethylene glycol (PEG) bound thereto, the surface structure of the liposome may be densified to delay the release of drug molecules encapsulated therein.

According to one side, the liposome particles may be dispersed in water at a concentration of 5 to 20 mg / ml.

According to one side, the drug may be present in the form encapsulated in the liposome particles.

According to another embodiment of the present invention, preparing a solution comprising 50-80 parts by weight of lipid and 20-80 parts by weight of cholesterol; Evaporating the solution to form a lipid film; Hydrating the lipid film with an acidic buffer solution to prepare a liposome solution; Mixing a basic buffer solution with the liposome solution; And inserting a cholinesterase inhibitor drug into the liposome; Including, a method for producing a liposome preparation is provided.

If the drug to be encapsulated is hydrophobic, it is easy to prepare liposome after eutectic with lipid and cholesterol.However, if the drug has high solubility in water such as physostigmine, the drug is rapidly released and encapsulated. There is a problem that the rate is significantly lowered, and the drug may be degraded under high temperature conditions to hydrate the liposomes. Therefore, in the case of drug groups that are hydrophilic and inferior in thermal stability, the preparation method of the present invention may be useful in that the liposome is prepared without the drug first, and then the drug is introduced into the liposome using the difference between the inside of the liposome and the external environment. In other words, when the pH of the liposome is lowered and the external pH is increased by using the characteristic of physostigmine which is positively charged at low pH and not charged at high pH, the drug existing outside the liposome can easily penetrate into the liposome. In addition, since the inside of the liposome has a positive charge, it is difficult to leak to the outside, and even a hydrophilic drug may be encapsulated in the liposome.

Since phosphatidylcholine constituting lipids has various phase transition temperatures in the range of 25 to 60 ° C. according to the number of carbon atoms of each molecule, the step of hydrating the prepared lipid film with an acidic buffer solution should be performed at 60 ° C. or higher. Lipids have a drawback that the liposome yield is lowered by the film portion that is not separated from the flask when the lipid is properly separated from the flask to form phospholipid double membrane particles while having fluidity.

Mixing the basic buffer solution with the liposome solution may determine the pH of the basic buffer solution in consideration of the ionization constant of the drug itself to be encapsulated. In order for the drug to penetrate into the liposome more effectively, after mixing the basic buffer solution, the pH value outside the liposome must be maintained at a level similar to or higher than the ionization constant of the drug. On the other hand, in case of physostigmine, the drug may be decomposed by the hydroxide ion when the pH value outside the liposome is excessively high, so that the liposome solution and the basic buffer solution are mixed with the liposome solution in the state dissolved in the basic buffer solution. Is first mixed to form a pH gradient inside and outside the liposome, then mixing the drug is advantageous to increase the drug stability.

According to one side, after the step of encapsulating in the liposome by the input of the cholinesterase inhibitor drug, using a semi-permeable membrane, dialysis in an excess of distilled water to obtain a purified liposome; may further include a.

According to one side, after the step of preparing the liposome solution, homogenizing the average particle size of the liposome to 50 to 200nm using an ultrasonic treatment or an extruder; It may further include. The homogenization step can increase the surface area and achieve reproducible drug encapsulation.

According to one side, the acidic buffer solution may be any one selected from the group consisting of formic acid, citric acid, acetic acid, hydrochloric acid, phosphoric acid, phthalate acid, the basic buffer solution is sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium carbonate, Sodium hydrogen carbonate, may be any one selected from the group consisting of sodium borate, but is not limited thereto.

Hereinafter, the present invention will be described in more detail with reference to Examples. The following examples are described for the purpose of illustrating the present invention, but the scope of the present invention is not limited thereto.

Example  1: the drug is Enclosed Liposome  Produce

After dissolving 80 mg of Lipoid E100, cholesterol, and 20 mg of egg yolk lecithin containing 95% or more of phosphatidylcholine in 10 ml of methanol, the solvent was evaporated at 60 ° C. using a rotary solvent evaporator. Subsequently, the lipid film was hydrated using 300 mM citric acid buffer at pH 3.0 to prepare a large size liposome. This was sonicated and passed through an extruder with a 0.2 μm pore size to prepare liposomes with a uniform particle size around 100 nm. 500 mM sodium carbonate buffer was added to the liposome dispersion to adjust the pH of the entire liquid phase to 9.0. 4 mg of physostigmine was added thereto so that the drug was introduced into the liposome by the pH difference between both sides of the lipid bilayer. Thereafter, to remove unsealed physostigmine and the electrolyte, a semi-permeable membrane was used for dialysis in an excess of distilled water to obtain purified liposomes.

Example  2: using PEG-phosphatidylcholine Liposome  Produce

Lipoid E100, a yolk lecithin containing more than 95% of 70 mg of phosphatidylcholine, 20 mg of cholesterol and 10 mg of polyethylene glycol 2000-phosphatidylcholine was dissolved in 10 ml of methanol, and the solvent was evaporated at 60 ° C. using a rotary solvent evaporator. Subsequently, the lipid film was hydrated using 300 mM citric acid buffer at pH 3.0 to prepare a large size liposome. This was sonicated and liposomes were passed through an extruder with a 0.2 μm pore size to prepare liposomes with a uniform particle size around 100 nm. 500 mM sodium carbonate buffer was added to the liposome dispersion to adjust the pH of the entire liquid phase to 9.0. 4 mg of physostigmine was added thereto so that the drug was introduced into the liposome by the pH difference between both sides of the lipid bilayer. Thereafter, to remove unsealed physostigmine and the electrolyte, a semi-permeable membrane was used for dialysis in an excess of distilled water to obtain purified liposomes.

Experimental Example  One: Liposome  Identification of physical and chemical properties

Prepared under the same conditions as in Examples 1 and 2, dissolving 4 mg of physostigmine in 500 mM sodium carbonate buffer, and then mixed in the order of mixing in the liposome dispersion liquid prepared in Comparative Examples 1 and 2. Physical and chemical properties such as drug encapsulation rate and particle size of Examples 1 and 2 and Comparative Examples 1 and 2 were confirmed. Particle size and polydispersity index of liposomes were measured using an electrophoretic light scattering particle size meter, and particle size distributions of liposomes prepared in Examples 1 and 2 are shown in FIGS. 1 and 2, respectively. The physostigmine concentration in the sample was measured using high performance liquid chromatography. The liposome dispersion was diluted with methanol to dissolve the liposomes and extract physostigmine. The drug concentration was calculated by calculating the amount of drug remaining after the preparation of liposomes relative to the total amount of drug injected by measuring the corresponding drug concentration. Particle size, polydispersity index and encapsulation rate of each composition of the Examples and Comparative Examples are shown in Table 1 below.

Referring to Table 1, the particle size of the prepared liposome is uniform to about 110nm, it can be seen that in the case of the inclusion rate is about 67% higher in Example 2 with polyethylene glycol derivative added. On the other hand, the liposomes of Comparative Examples 1 and 2 were significantly lower than the sealing rate of 7.5 ± 0.3%, 16.3 ± 3.2% compared to Examples 1 and 2. This improves the drug stability when the physostigmine is exposed to less severe base conditions during the drug encapsulation process, thereby increasing the encapsulation rate, and the encapsulation rate can be significantly improved when the polyethylene glycol-phosphatidylcholine is added during liposome preparation. It can be seen.

Experimental Example  2: Liposome  Morphological Characterization

In order to confirm the morphological characteristics of the prepared liposomes, the shape of the liposome particles was observed using a transmission electron microscope. The liposome suspension was adsorbed onto a copper grid and observed after particle dyeing, dye removal and drying. 3 and 4 show the electron micrographs of the liposomes prepared in Examples 1 and 2, it can be seen that the particles of the size similar to the particle size measured by the particle size measurement in Experimental Example 1 through this.

Experimental Example  3: Liposome  Drug Release Experiment

Drug release experiments were performed to confirm the release of the drug from the liposomes. Considering that the liposomes are nano-sized, drug release experiments were performed using a semipermeable dialysis membrane. A liposome dispersion containing a certain amount of drug was contained in a semipermeable membrane (molecular weight cut-off 12,000-14,000 Da), and this was eluted at 37 ° C using phosphate buffer as an eluent. In the control group, the drug solution not encapsulated in liposomes was placed in the semipermeable membrane and eluted from the eluate. The eluate was partially taken out of the membrane over time to replenish the same amount of eluate. At this time, in order to minimize the decomposition of physostigmine under high temperature conditions, sodium metabisulfite, which inhibits the decomposition reaction, was dissolved in 5 mg / ml. The drug concentration of the collected eluate was measured using high performance liquid chromatography, and the release rate was calculated using this. 5 shows a graph of drug release over time through the analysis results. Referring to FIG. 5, the drug solution not encapsulated in liposomes was released most of drugs within 2-4 hours, but the liposome preparations of Examples 1 and 2 were slowly released over 24 hours. In particular, the liposome of Example 2 containing polyethyleneglycol-phosphatidylcholine was released slowly compared to the liposome of Example 1 until 20 hours after the start of drug release. Through this, it can be seen that when the drug is encapsulated in liposomes, the sustained release of the drug is possible.

Experimental Example  4: Liposomes  Intrabody Administration of the Formulation

The pharmacokinetic properties of rats were evaluated in order to observe the blood concentration change over time after the liposomes prepared in Examples 1 and 2 subcutaneously. After the abdomen of the immobilized rat was depilated, the physostigmine solution of the same contents as the drugs enclosed in Examples 1 and 2, and the liposome preparations of Examples 1 and 2 were subcutaneously injected into the abdomen. Thereafter, plasma was collected at each time to measure drug concentration. Drug concentrations in plasma samples were analyzed using a mass spectrometer. The results of analyzing blood concentrations over time after administration of physostigmine at a 100 μg / kg dose are shown in FIG. 6, and the pharmacokinetic parameters calculated based on the change in blood concentration are shown in Table 2 below.

parameter Physostigmine Example 1 Example 2 C _max (ng / mL) 55.03 ± 7.50 11.98 ± 1.68 12.92 ± 1.46 T _max (min) 15.00 ± 0.00 30.00 ± 25.98 30.00 ± 17.32 AUC _last (ngmin / mL) 1708.40 ± 200.99 1493.77 ± 152.45 2567.70 ± 257.00 AUC _inf (ngmin / mL) 1730.18 ± 200.93 1616.90 ± 183.78 2976.71 ± 305.36 t _1/2 (min) 36.77 ± 4.72 120.76 ± 29.54 159.59 ± 25.86 MRT (min) 36.52 ± 5.36 130.86 ± 17.27 157.60 ± 12.21

Referring to Table 2, the subcutaneous injection of physostigmine solution showed a peak blood concentration of 55.03 ng / ml and rapid disappearance (half-life 36.77 minutes), while the relatively low peak blood concentration (11.98 ng) for liposome preparations. / ml) was maintained for about 1 hour and then the concentration gradually decreased. In addition, the liposome preparation of Example 2 containing polyethyleneglycol-phosphatidylcholine was gradually decreased after maintaining the blood concentration (12.92 ng / ml) similar to that of Example 1 for about 2 hours. Through these results, it can be seen that when the liposome preparation of the present invention is injected subcutaneously, the blood concentration is lowered for a long time than the conventional solution preparation. This is consistent with the fact that the drug is slowly released from the liposome in the drug release test of Experimental Example 3.

In addition, the maximum blood concentration can be lowered by using the liposome preparation of the present invention. Considering that cholinergic symptoms may occur according to the blood concentration of physostigmine, the liposome preparation of the present invention is rapidly absorbed into the blood. Suggests that it may have the effect of mitigating toxicity.

Experimental Example  5: blood Of cholinesterase  Active comparison

Changes in the activity of enzymes present in the blood were measured over time. In the blood, cholinesterase enzymes break the ester bonds of acetylcholine, which can be inhibited by cholinesterase inhibitors such as physostigmine to decrease the rate of degradation of acetylcholine. Blood enzyme activity was measured using the Elllman reaction based on the above mechanism. After plasma was collected under the same conditions as in Experiment 4, acetylthiocholine, a substance that could be a substrate of cholinesterase, was reacted with plasma for 5 minutes. After the reaction, 5,5'-dithiobis (2-nitrobenzoic acid) (DTNB) was mixed and reacted with the degradation product, thiocholine, to measure the yellow color development. In the above method, if the concentration of physostigmine in the blood is high, cholinesterase activity decreases and the amount of thiocholine generated for a certain period of time decreases, thereby reducing the intensity of the color signal generated in response to DTNB.

Figure 7 is a graph showing the change in the rate of inhibition of blood cholinesterase with time, it can be seen that the pattern is somewhat similar to the trend of blood drug concentration over time. Referring to FIG. 7, the subcutaneous injection of physostigmine solution inhibited the enzyme close to 50% at first, but the inhibition thereof rapidly decreased with time. On the other hand, in the case of subcutaneous injection of the liposome preparations of Examples 1 and 2 showed an enzyme inhibition of less than 30%, it can be seen that the inhibition is gradually reduced compared to the solution. In addition, the liposome preparation of Example 2 showed a high degree of enzyme inhibition as a whole compared to the liposome preparation of Example 1. These results suggest that subcutaneous injection of drugs in the form of liposome preparations may continue to show lower efficacy than conventional drug solutions.

Although the embodiments have been described by the limited embodiments and the drawings as described above, various modifications and variations are possible to those skilled in the art from the above description. For example, the techniques described may be performed in a different order than the described method, and / or the components described may be combined or combined in a different form than the described method, or replaced or substituted by other components or equivalents. Appropriate results can be achieved.

Therefore, other implementations, other embodiments, and equivalents to the claims are within the scope of the following claims.

Claims (12)

As a subcutaneous injectable preparation in which liposome particles containing 1-5 parts by weight of physostigmine, 60-70 parts by weight of egg yolk lecithin, 10-20 parts by weight of polyethylene glycol-phosphatidylcholine and 20-80 parts by weight of cholesterol are dispersed in water. , The physostigmine is present in the form encapsulated in the liposome particles, subcutaneous injection formulation.
delete delete The method of claim 1,
The liposome particles are dispersed in water at a concentration of 5 to 20 mg / ml, subcutaneous injection formulation.
delete Preparing a solution comprising 60-70 parts by weight of yolk lecithin-derived phosphatidylcholine, 10-20 parts by weight of polyethylene glycol-phosphatidylcholine and 20-80 parts by weight of cholesterol;
Evaporating the solution to form a lipid film;
Hydrating the lipid film with an acidic buffer solution to prepare a liposome solution;
Mixing a basic buffer solution with the liposome solution; And
Inserting physostigmine into the liposome; It comprises a, method for producing a liposome formulation.
The method of claim 6,
After the step of encapsulating in the liposomes by adding the physostigmine, dialysis in an excess of distilled water using a semi-permeable membrane to obtain a purified liposomes; further comprising, preparing a liposome preparation.
The method of claim 6,
After preparing the liposome solution, homogenizing the average particle size of the liposome to 50 to 200 nm using an ultrasonic treatment or an extruder; Further comprising, method for producing a liposome preparation.
The method according to any one of claims 6 to 8,
The acid buffer solution, any one selected from the group consisting of formic acid, citric acid, acetic acid, hydrochloric acid, phosphoric acid and phthalate acid, method of producing a liposome preparation.
The method according to any one of claims 6 to 8,
The basic buffer solution, sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium carbonate, sodium hydrogen carbonate and sodium borate, any one selected from the group consisting of, the preparation method of a liposome preparation.
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