Costus oil emulsion with spleen targeting function as well as preparation method and application of costus oil emulsion

Abstract

The invention discloses costus oil emulsion with a spleen targeting function as well as a preparation method and application of the costus oil emulsion, and belongs to the technical field of targeted release. The costus oil emulsion comprises costus oil, a liquid-phase surfactant and a liquid-phase entrapment matrix, the volume ratio of the costus oil to the entrapment matrix is 1: 9-1.5: 8.5, the liquid-phase entrapment matrix is a thickening agent or an emulsifying agent, and the surfactant is Tween 80. The preparation method comprises the following steps: mixing the liquid-phase entrapped matrix with costus oil and the liquid-phase surfactant, and homogenizing to obtain the costus oil. The thickening agent or the emulsifying agent is adopted as an entrapment matrix, costus oil is uniformly dispersed in a water phase through the excellent thickening property and emulsifying stability of the thickening agent or the emulsifying agent, a stable oil-in-water (O / W) emulsion is formed, the obtained system can effectively inhibit volatilization and oxidative degradation of costus oil, the storage life of the costus oil can be prolonged, and the using effect of the costus oil can be improved. In addition, the costus oil has the potential of immunoregulation or targeted delivery, and new possibility is provided for application of the costus oil in the field of medicine.

Description

Technical Field

[0001] The present invention belongs to the technical field of targeted release, and in particular relates to a costus root oil emulsion with spleen targeting function, and a preparation method and application thereof. Background Art

[0002] Oral administration is the most accessible, cost-effective, and patient-compliant route of administration. However, this approach must overcome the complex physiological and chemical barriers of the digestive tract. The acidic environment of the stomach (pH 1-3) and pepsin can lead to drug degradation; the rapid turnover of the intestinal mucus layer (completely replaced every 4-6 hours) hinders drug penetration; and the tightly connected epithelial cell layer limits the absorption of large molecular drugs (e.g., insulin bioavailability <1%). The synergistic effect of these barriers leads to a significant reduction in drug bioavailability, with a particularly prominent impact on biomacromolecules (e.g., proteins and nucleic acids). Current studies have found that after oral administration, drug absorption and distribution are more concentrated in localized areas of the gastrointestinal tract. Targeting outside the gastrointestinal tract is currently difficult to achieve, and drugs must first traverse the immune barrier of the gut-associated lymphoid system and the first-pass effect of the portal vein system before entering the systemic circulation and targeting the spleen. However, to date, no simple and feasible solution has been developed for targeted delivery to specific target organs such as the spleen via the oral route of administration.

[0003] The spleen, the largest secondary lymphoid organ in the human body, is composed of white pulp, red pulp, and the marginal zone. It harbors a rich population of immune cells, including B cells, T cells, dendritic cells (DCs), and macrophages, which play a key role in immune regulation and antigen presentation. Targeted spleen delivery technologies hold great promise for the treatment of cancer, genetic disorders, autoimmune diseases, and infectious diseases. Currently, strategies for spleen targeting include modifying lipid nanoparticle (LNP) composition, exploiting the homing effect of senescent red blood cells, targeting DCs, B cells, and T cells in the spleen, and exploiting neutrophil "hitchhiking." Although intravenous LNPs can achieve spleen targeting through systemic circulation, their design and preparation are significantly complex. To achieve selective accumulation in the splenic red pulp, precise control of the ionized lipid structure, optimization of the helper lipid composition, and even the incorporation of apoptotic cell membrane-mimicking strategies are required. This structural complexity not only complicates the production process but also limits the feasibility of large-scale production and clinical application. Currently, research focuses primarily on intravenous administration, which, however, presents numerous limitations. First, intravenous injection is inconvenient, leads to low patient compliance, and is invasive and carries risks such as infection and thrombosis. More importantly, intravenously injected LNPs are easily taken up by the liver, resulting in inefficient spleen targeting and compromised therapeutic efficacy. Furthermore, intravenous injection can cause inflammatory reactions, further limiting its clinical application.

[0004] Therefore, developing an oral delivery system that can effectively overcome the above limitations and achieve efficient spleen targeting has important clinical application prospects and research value.

[0005] Aucklandia lappa decne, a plant of the Asteraceae family, has a pungent and bitter nature. Its dried root is used as a medicinal substance, promoting spleen and digestion, promoting qi circulation, and alleviating pain. Modern research indicates that the pharmacological activity of Aucklandia lappa decne stems primarily from its abundant volatile oils and sesquiterpenoids, including costunolide and dehydrocostuslactone. The pharmacological effects of Aucklandia lappa decne's volatile oils have been shown to be associated with gastrointestinal motility regulation, anti-inflammatory effects, and neuroendocrine regulation. Currently available Chinese patent medicines and preparations containing costus root include Muxiang Shunqi Pills, Xianglian Pills, Guipi Decoction Concentrated Powder, Bawei Tongjing Granules / Tablets, Ejiao Pearl Paste, Sanjiu Weitai, Shugan Pills, Muxiang Binglang Pills, Suhexiang Pills, Weichang An Pills, Xiangsha Liujunzi Pills, Liuwei Muxiang Pills / Capsules, Bawei Rougui Capsules, Dahuoluo Pills, Zhachong Shisanwei Pills, Shenjin Huoluo Pills, Maren Runchang Pills, Yueju Baohe Pills, Jiuwei Niuhuang Pills, Chenxianglu Bailu Tablets, Xinkeshu Tablets, Compound Chenxiangwei Tablets, Simotang Oral Liquid, and Bawei Hewei Oral Liquid. Currently available medications containing costus root are primarily compound formulations, and are often used for digestive system disorders (such as abdominal distension and pain), gynecological conditions, and qi and blood conditioning.

[0006] However, existing research on costus root faces the following key bottlenecks that hinder its clinical translation, including unclear in vivo mechanisms of action: the lack of a clear correlation between oral biodistribution characteristics (such as intestinal absorption rate and target organ enrichment) and the metabolic pathways underlying its spleen-tonifying effect, leading to a lack of pharmacokinetic basis for dosage design; the inherent low boiling point of the volatile oil results in poor formulation stability, and high concentrations of free volatile oil in direct contact with the gastrointestinal mucosa can induce irritation reactions such as nausea and mucosal congestion. Therefore, there is an urgent need to develop a delivery system that can regulate the gastrointestinal release of costus root volatile oil to match the physiological rhythm of its spleen-tonifying effect, while reducing mucosal irritation while retaining the rapid-release properties of its volatile oil. Summary of the Invention

[0007] Purpose of the invention: In order to solve the problems existing in the prior art, the first purpose of the present invention is to provide a costus root oil emulsion with spleen targeting function, which has a simple preparation process and good stability. The second purpose of the present invention is to provide a preparation method of the above costus root oil emulsion. The third purpose of the present invention is to provide an application of the above costus root oil emulsion.

[0008] Technical solution: The costus root oil emulsion with spleen targeting function described in the present invention comprises costus root oil, a liquid surfactant and a liquid encapsulation matrix. The volume ratio of the costus root oil to the encapsulation matrix is 1:9-1.5:8.5, preferably 1:9.

[0009] In the costus root oil emulsion, as the proportion of costus root oil in the oil phase increases, demulsification will easily occur. When the same volume of costus root oil and encapsulation matrix (volume ratio of 1:9) and costus root oil and encapsulation matrix (volume ratio of 2:8) emulsions were injected in preliminary experiments on animals, mice in the 2:8 group died.

[0010] Furthermore, the volume ratio of the liquid surfactant to costus root oil is 1:4-1:7, preferably 1:6.25.

[0011] Furthermore, the entrapment matrix is a thickener or emulsifier, such as xanthan gum, tamarind polysaccharide or methylcellulose sol.

[0012] Preferably, the liquid-phase entrapment matrix is a methylcellulose sol, which is composed of methylcellulose and a solvent in a mass ratio of 2.5-3:100. If the amount of methylcellulose is too low, the sol will be too dilute, and if the amount of methylcellulose is too high, the sol will not form and will directly solidify and cannot be used. Methylcellulose is a naturally derived polymer material with good biocompatibility and no toxic side effects. Due to its excellent gel properties and good biocompatibility and safety, it is used in the field of drug delivery.

[0013] Furthermore, the surfactant is Tween 80, chosen for its: ① High emulsification ability: It can effectively reduce oil-water interfacial tension to form a stable emulsion; ② Broad compatibility: It is easily soluble in solvents such as water, ethanol, and vegetable oils, and is highly resistant to electrolytes and high and low pH environments; ③ Versatility: It has solubilizing, wetting, and dispersing properties; ④ High stability: It can maintain the emulsification effect for a long time in complex formulations such as pharmaceuticals and cosmetics, preventing phase separation; ⑤ High safety: As a non-ionic surfactant, it has passed rigorous safety assessments in the food and pharmaceutical fields.

[0014] Furthermore, the costus root oil emulsion also includes immune stimulants, including cationic liposomes, adenosine monophosphate, glycopolypeptides, lactoferrin, stearate and polysaccharides. The use of these ingredients in the emulsion not only improves the stability of the emulsion, but also provides a new way for immune regulation.

[0015] The preparation method of the costus root oil emulsion of the present invention comprises the following steps: mixing a liquid phase encapsulation matrix with costus root oil and a liquid phase surfactant, and homogenizing the mixture to obtain the emulsion.

[0016] Furthermore, the homogenization process parameters are: rotation speed of 10000-15000 r / min, and dispersion time of 2-10 min.

[0017] Furthermore, when the liquid-phase encapsulation matrix is methylcellulose sol, the preparation steps are: mixing methylcellulose and a solvent, stirring to fully dissolve, and swelling overnight to obtain the methylcellulose sol.

[0018] Furthermore, the dissolving temperature is 40-70°C.

[0019] The invention relates to the use of the costus root oil emulsion as an oral administration spleen-targeted drug delivery platform.

[0020] Beneficial effects: Compared with the prior art, the present invention has the following significant effects: (1) Significantly improves the stability of costus root oil: Costus root oil, as a natural plant essential oil, has a unique aroma and potential medicinal value, but its high volatility and susceptibility to oxidation limit its application. The present invention adopts the preferred methyl cellulose as the encapsulation matrix, and through its excellent thickening and emulsification stability, the costus root oil is uniformly dispersed in the aqueous phase to form a stable oil-in-water (O / W) emulsion. This system can not only effectively inhibit the volatilization and oxidative degradation of costus root oil, but also prolong its storage period and use effect; (2) Unique in vivo distribution characteristics and targeting: In the in vivo distribution experiment of mice, the costus root oil emulsion of the present invention showed a significant spleen enrichment effect compared with the squalane emulsion control group. This characteristic indicates that the costus root oil emulsion of the present invention may have immunomodulatory effects. or targeted delivery, which provides new possibilities for the application of costus root oil in the medical field; (3) Green and safe, simple process: methylcellulose, as a natural polymer material, is used in the field of drug delivery due to its excellent gel properties and good biocompatibility and safety. It also has the advantages of stable chemical properties and easy availability of raw materials, which is in line with the development trend of modern green chemistry. The surfactant Tween 80 used has the advantages of high emulsification ability, wide compatibility, stability and high safety. At the same time, the preparation process of the present invention is simple and controllable, easy to mass produce, and has high industrial application value. In summary, the present invention not only solves the technical problems of costus root oil being easy to volatilize and oxidize, but also gives it unique in vivo distribution characteristics, providing an innovative solution for the efficient utilization of natural essential oils. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a microscopic image of the costus root oil emulsion in Example 1;

[0022] Figure 2 This is the morphology of the squalane emulsion under a microscope in Comparative Example 1;

[0023] Figure 3 Graphs showing the stability of the costus root oil emulsion prepared in Example 1 and its effects in gastric juice (pH = 1.5) and phosphate buffer solutions (pH = 5.5, 6.5, 7.4, 8.5) from day 0 to day 5;

[0024] Figure 4 The present invention is a statistical graph of the fluorescence enrichment intensity of the brain, heart, lung, kidney, spleen and liver of babl / c mice after gavage with DIR dye, squalane emulsion (DIR labeling) and costus root oil emulsion (DIR labeling) for 8 hours. DETAILED DESCRIPTION

[0025] The present invention is further described in detail below with reference to the embodiments and accompanying drawings.

[0026] Example 1: The costus root oil emulsion with spleen targeting function described in this example includes costus root oil, liquid surfactant Tween 80 and liquid encapsulation matrix methylcellulose (MC) sol, and the volume ratio of costus root oil to encapsulation matrix is 1:9.

[0027] The preparation method is as follows:

[0028] (1) Preparation of methylcellulose (MC) sol: 3 g of MC was weighed and dissolved in 100 mL of deionized water. The MC was fully dissolved at 60°C and then swelled at 4°C overnight.

[0029] (2) Preparation of MC@Costus oil-Emulsion: Accurately pipette 5 mL of costus oil, 45 mL of methylcellulose (MC) sol, and 0.8 mL of Tween 80, and mix them with a high-speed homogenizer at a speed of 10,000 r / min for 5 minutes to obtain MC@Costus oil-Emulsion. Figure 1 As shown, the emulsion is circular.

[0030] Comparative Example 1: Preparation of Squalane-Emulsion: Accurately pipette 5 mL of squalane (Costus oil) and 45 mL of methylcellulose (MC) sol (prepared from 3 g of MC and 100 mL of deionized water) and 0.8 mL of Tween 80, and mix them at a high-speed homogenization speed of 10,000 r / min for 5 minutes to obtain Squalane-Emulsion. Figure 2 As shown, the emulsion is circular.

[0031] Stability test:

[0032] Solution A (0.2 M sodium dihydrogen phosphate aqueous solution): Dissolve 27.6 g of NaH2PO4·H2O in distilled water and dilute to 1000 ml.

[0033] Solution B (0.2 M sodium hydrogen phosphate aqueous solution): Dissolve 53.6 g of Na2HPO4·7H2O in distilled water and add water to 1000 ml.

[0034] Preparation of pH 5.5 buffer: Add 93.5 mL of solution A and 6.5 mL of solution B. The pH is now 5.7. Use a pH meter to accurately calibrate. Add solution A / solution B to bring the pH to 5.5.

[0035] Preparation of pH 6.5 buffer: Add 68.5 ml of solution A and 7.7 ml of solution B. The pH is now 6.5. Use a pH meter for accurate calibration.

[0036] Preparation of pH 7.4 buffer: Add 10 mL of solution A and 90 mL of solution B. The pH is now 7.7. Use a pH meter to accurately calibrate. Add solution A / solution B until the pH reaches 7.4.

[0037] Preparation of pH=8.5 buffer: Add 5.3 ml of the above solution A and 94.7 mL of solution B. At this time, the pH = 8.0. Use a pH meter for accurate calibration and add solution A / solution B to make the pH = 8.5.

[0038] Stability test of simulated emulsion under different pH conditions in vivo after oral administration, such as Figure 3 1.5mL of MC@Costus oil-Emulsion was mixed with 1.5mL of artificial gastric fluid and buffer solutions of different pH values (5.5, 6.5, 7.4, and 8.5). The stability of the emulsions was observed at 0h, 2h, 24h, and 5 days. At 24h, no significant stratification was observed in the emulsions in each group, suggesting that the emulsions maintain good stability in vivo and are not easily destroyed. On the 5th day, stratification began to appear in the different pH buffer groups, indicating that the emulsions were beginning to degrade. However, the MC@Costus oil-Emulsion maintained good stability and was observed until the 35th day, at which point slight oil-water stratification appeared in the emulsions.

[0039] Application testing:

[0040] Costus root oil and squalane were labeled with DiR, and then costus root oil emulsion and squalane emulsion were prepared according to the methods of Example 1 and Comparative Example 1.

[0041] Solution preparation for the DiR group: DiR was dissolved in DMSO and then diluted with water;

[0042] The drugs in each administration group contained the same concentration of DiR.

[0043] BALB / c mice were randomly divided into three groups (n=5) and administered DiR fluorescent dye (control group), methylcellulose-encapsulated squalane emulsion (Squalane-Emulsion), and methylcellulose-encapsulated costus oil emulsion (MC@Costus oil-Emulsion) via oral gavage. Eight hours after administration, the mice were sacrificed and their major organs (brain, heart, lungs, kidneys, spleen, and liver) were dissected. The fluorescence intensity distribution of each organ was measured using an in vivo imaging system. Figure 4 As shown in the figure, quantitative analysis showed that the fluorescence signal intensity in the spleen of mice in the MC@Costus oil-Emulsion group was significantly higher than that in the DiR control group and the Squalane-Emulsion group, indicating that the preparation has significant spleen-targeted enrichment properties. This result suggests that the methylcellulose emulsion system can change the distribution pattern of costus oil in vivo and provides an experimental basis for the development of spleen-targeted drug delivery systems.

Claims

1. A costus root oil emulsion with spleen targeting function, characterized in that: The invention comprises costus root oil, a liquid phase surfactant and a liquid phase inclusion matrix, wherein the volume ratio of the costus root oil to the inclusion matrix is 1:9-1.5:8.

5.

2. The costus root oil emulsion according to claim 1, characterized in that The volume ratio of the liquid phase surfactant to costus root oil is 1:4-1:

7.

3. The costus root oil emulsion according to claim 1, characterized in that The liquid phase inclusion matrix is a thickener or an emulsifier.

4. The costus root oil emulsion according to claim 3, characterized in that The liquid phase encapsulation matrix is methyl cellulose sol; the methyl cellulose sol is composed of methyl cellulose and solvent in a mass ratio of 2.5-3:

100.

5. The costus root oil emulsion according to claim 1, characterized in that The surfactant is Tween 80.

6. The costus root oil emulsion according to claim 1, characterized in that The costus root oil emulsion also includes an immune stimulant.

7. A method for preparing the costus root oil emulsion according to claim 1, characterized in that: The method comprises the following steps: mixing a liquid-phase encapsulation matrix, costus root oil and a liquid-phase surfactant, and homogenizing the mixture to obtain the product.

8. The preparation method according to claim 7, characterized in that The process parameters of the homogenization are: rotation speed of 10000-15000 r / min, and dispersion time of 2-10 min.

9. The preparation method according to claim 7, characterized in that When the liquid-phase entrapment matrix is methylcellulose sol, the preparation steps are: mixing methylcellulose and a solvent, stirring to fully dissolve at 40-70° C., and swelling overnight to obtain the methylcellulose sol.

10. Use of the costus root oil emulsion according to any one of claims 1 to 6 as a spleen-targeted drug delivery platform for oral administration.

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