Sustained-release iron supplementing compound and preparation method thereof

Abstract

The invention relates to the technical field of iron-supplementing compounds, in particular to a slow-release iron-supplementing compound and a preparation method thereof. The preparation method comprises the following steps: dispersing ferric salt in a solvent to obtain a dispersion solution, and adding amino acid into the dispersion solution to obtain an amino acid solution; the preparation method comprises the following steps: mixing lecithin and polyol, homogenizing to obtain an emulsion, dropwise adding chitosan into the emulsion, and stirring to obtain a polysaccharide solution; dropwise adding the amino acid solution into the polysaccharide solution, stirring, and adding an inorganic filler to obtain a composite solution; and centrifuging the composite solution, and collecting the precipitate to obtain the slow-release iron-supplementing compound. According to the invention, the bioavailability of iron can be improved, and excessive release of free iron ions is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of iron supplement compounds, and in particular to a sustained-release iron supplement compound and a preparation method thereof. Background Art

[0002] Iron is one of the essential trace elements for the human body. It is widely involved in the synthesis of hemoglobin, myoglobin and various enzymes, and plays a vital role in maintaining normal physiological functions of the human body. Iron deficiency can cause anemia, decreased immune function, fatigue and other health problems, especially for women, children and the elderly.

[0003] At present, iron supplement products on the market mainly include inorganic iron salts (such as ferrous sulfate, ferric chloride) and organic iron compounds (such as ferrous gluconate, ferrous lactate, etc.). However, although inorganic iron salts have low costs, they are highly water-soluble and easily hydrolyze in the gastrointestinal tract to form insoluble iron hydroxide precipitates, resulting in low bioavailability of iron. Due to their high solubility, inorganic iron salts and some organic iron compounds will release excessive free iron ions in the gastrointestinal tract, which can easily irritate the gastrointestinal mucosa, resulting in excessive absorption, and easily causing adverse reactions such as nausea, vomiting, and diarrhea. Summary of the invention

[0004] In view of the above-mentioned shortcomings of the prior art, the object of the present invention is to provide a sustained-release iron supplement compound and a preparation method.

[0005] The technical solution of the present invention to solve the above technical problems is as follows: The preparation method of the sustained-release iron supplement compound comprises the following steps: The iron salt is dispersed in a solvent to obtain a dispersed solution, and amino acids are added to the dispersed solution to obtain an amino acid solution; The lecithin and the polyol are mixed and homogenized to obtain an emulsion, chitosan is added dropwise to the emulsion, and stirred to obtain a polysaccharide solution; The amino acid solution is added dropwise to the polysaccharide solution, stirred, and an inorganic filler is added to obtain a composite solution; The complex solution is centrifuged, and the precipitate is collected to obtain a sustained-release iron supplement compound.

[0006] Based on the above technical solution, the present invention can also be improved as follows.

[0007] Preferably, the amino acid includes at least one of lysine and glutamic acid.

[0008] Preferably, the chitosan includes at least one of carboxymethyl chitosan and sodium alginate.

[0009] Preferably, the polyol comprises glycerol.

[0010] Preferably, the chitosan is a chitosan solution, and the concentration of the chitosan solution is 1-5%.

[0011] Preferably, when amino acids are added to the dispersed solution, the concentration of the amino acids is 1-5%.

[0012] Preferably, the polyol is a polyol aqueous solution, and the volume ratio of the polyol to water is 1-5:5-7.

[0013] Preferably, the iron salt includes at least one of ferric protein succinate, ferric citrate and ferrous lactate.

[0014] Preferably, the inorganic filler includes silicon dioxide, and the silicon dioxide includes nano silicon dioxide.

[0015] The sustained-release iron-supplement compound is prepared according to the aforementioned method for preparing the sustained-release iron-supplement compound.

[0016] Different from the prior art, the advantages of the present invention are: First, the present invention can improve the bioavailability of iron: the present invention forms a stable core layer solution by compounding iron salt with amino acid, thereby enhancing the solubility and stability of iron ions and effectively avoiding the phenomenon of iron ions forming insoluble precipitation in the gastrointestinal tract. The sustained release effect of the coating layer solution (carboxymethyl chitosan and lecithin) combined with inorganic fillers further optimizes the release rate of iron ions and prolongs the absorption time of iron ions, thereby significantly improving the bioavailability of iron.

[0017] Second, the present invention can avoid excessive release of free iron ions: the present invention controls the release rate of iron ions through sustained-release technology, avoiding the release of a large amount of iron ions in a short period of time, thereby reducing the concentration of free iron ions in the gastrointestinal tract and alleviating its irritation to the gastrointestinal mucosa. In addition, lysine, as an amino acid, has good biocompatibility, which can further alleviate gastrointestinal discomfort and improve the comfort of taking.

[0018] Third, the materials are safe and have good biocompatibility: the raw materials used in the present invention, including iron protein succinate, lysine, carboxymethyl chitosan, lecithin and nano-silicon dioxide, are all materials with high safety and good biocompatibility, and no harmful by-products are produced during the sustained-release process. DETAILED DESCRIPTION

[0019] The principles and features of the present invention are described below, and the examples are only used to explain the present invention and are not used to limit the scope of the present invention. If no specific technology or conditions are specified in the embodiments, the technology or conditions described in the literature in this field or the product instructions are used. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased through regular channels.

[0020] Example 1 The preparation method of the sustained-release iron supplement compound comprises the following specific steps: Preparation of core layer solution: 10 g of iron protein succinate was added to 100 mL of purified water and dispersed at 8000 rpm for 10 min to obtain a dispersed solution. 4% lysine solution was prepared using lysine and purified water.

[0021] 20 mL of 4% lysine solution was added to the dispersed solution, ultrasonically treated at 300 W for 3 min, and the pH was adjusted to 6.5 to obtain an amino acid solution.

[0022] Preparation of coating solution: Prepare 2% carboxymethyl chitosan solution with carboxymethyl chitosan and purified water. Prepare glycerol aqueous solution at a volume ratio of glycerol to water of 3:7.

[0023] 6 g of lecithin and 200 mL of glycerol aqueous solution were mixed and homogenized twice at 500 bar to obtain an emulsion. 100 mL of 2% carboxymethyl chitosan solution was slowly added dropwise to the emulsion at a frequency of 1.5 mL / min and stirred at 400 rpm to obtain a polysaccharide solution.

[0024] Compounding: Slowly add the amino acid solution to the polysaccharide solution at 2 mL / min, stir at 400 rpm for 1 h, then add 2 g of nano-silicon dioxide and stir evenly to obtain a composite solution.

[0025] Separation: The composite solution was centrifuged at 5000 rpm for 10 min, the precipitate was collected, washed twice with purified water, and dried to obtain a sustained-release iron supplement compound.

[0026] It should be noted that The present application is prepared in this way to form a two-layer structure, with a core layer and a composite coating layer.

[0027] In the core layer: Iron protein succinate is the main active ingredient, providing iron with good bioavailability. Lysine can promote the absorption of iron and provide essential amino acids. Iron protein succinate forms a stable chelate with lysine, specifically an Fe-lysine coordination complex, which can enhance the stability of iron ions, improve biocompatibility, reduce free iron ions, and thus improve the sustained release performance of iron.

[0028] In the coating layer: carboxymethyl chitosan provides a sustained-release skeleton, which can form an electrostatic interaction with the core layer, increase adhesion and biocompatibility. Lecithin, as an emulsifier, can form liposomes and construct a biological membrane-like structure. Lecithin and carboxymethyl chitosan form self-assembled nanocarriers, which can enhance cell membrane permeability. Glycerol, as a plasticizer, can improve the flexibility of the coating layer and enhance stability.

[0029] Carboxymethyl chitosan is combined with an emulsifying system of glycerol and lecithin. Carboxymethyl chitosan can be more evenly distributed on the surface of the complex during the coating process, forming a shell layer with a porous structure, thereby improving the sustained release effect. Lecithin can optimize the uniformity and density of the coating layer, which helps to achieve the slow release of iron.

[0030] Nano-silicon dioxide is also added. As a functional filler, nano-silicon dioxide can be adsorbed on the surface of the composite, further improving the density and mechanical strength of the coating, while also having the ability to regulate release. After combining with other components, nano-silicon dioxide further enhances the physical strength of the coating and forms a porous network structure on the surface of the composite, further helping to regulate the release rate of iron.

[0031] In addition, the coating structure can also protect the protein in the iron salt from being destroyed.

[0032] Example 2 Different from Example 1, lysine is replaced by glutamic acid, and the rest remains unchanged.

[0033] Example 3 Different from Example 1, the 2% carboxymethyl chitosan solution was replaced with a 3% carboxymethyl chitosan solution, while the rest remained unchanged.

[0034] Comparative Example 1 Different from Example 1, no lysine was added in this comparative example.

[0035] The preparation method of the iron supplement compound comprises the following specific steps: Preparation of core layer solution: 10 g of iron protein succinate was added to 100 mL of purified water and dispersed at 8000 rpm for 10 min to obtain a dispersed solution.

[0036] Preparation of coating solution: Prepare 2% carboxymethyl chitosan solution with carboxymethyl chitosan and purified water. Prepare glycerol aqueous solution at a volume ratio of glycerol to water of 3:7.

[0037] 6 g of lecithin and 200 mL of glycerol aqueous solution were mixed and homogenized twice at 500 bar to obtain an emulsion. 100 mL of 2% carboxymethyl chitosan solution was slowly added dropwise to the emulsion at a frequency of 1.5 mL / min and stirred at 400 rpm to obtain a polysaccharide solution.

[0038] Compounding: slowly add the dispersed solution into the polysaccharide solution at 2 mL / min, stir at 400 rpm for 1 h, then add 2 g of nano-silicon dioxide and stir evenly to obtain a composite solution.

[0039] Separation: The composite solution was centrifuged at 5000 rpm for 10 min, the precipitate was collected, washed twice with purified water, and dried to obtain an iron supplement compound.

[0040] Comparative Example 2 Different from Example 1, no nano silicon dioxide is added in this comparative example.

[0041] The preparation method of the iron supplement compound comprises the following specific steps: Preparation of core layer solution: 10 g of iron protein succinate was added to 100 mL of purified water and dispersed at 8000 rpm for 10 min to obtain a dispersed solution. 4% lysine solution was prepared using lysine and purified water.

[0042] 20 mL of 4% lysine solution was added to the dispersed solution, ultrasonically treated at 300 W for 3 min, and the pH was adjusted to 6.5 to obtain an amino acid solution.

[0043] Preparation of coating solution: Prepare 2% carboxymethyl chitosan solution with carboxymethyl chitosan and purified water. Prepare glycerol aqueous solution at a volume ratio of glycerol to water of 3:7.

[0044] 6 g of lecithin and 200 mL of glycerol aqueous solution were mixed and homogenized twice at 500 bar to obtain an emulsion. 100 mL of 2% carboxymethyl chitosan solution was slowly added dropwise to the emulsion at a frequency of 1.5 mL / min and stirred at 400 rpm to obtain a polysaccharide solution.

[0045] Compounding: Slowly add the amino acid solution into the polysaccharide solution at a rate of 2 mL / min and stir at 400 rpm for 1 h to obtain a compound solution.

[0046] Separation: The composite solution was centrifuged at 5000 rpm for 10 min, the precipitate was collected, washed twice with purified water, and dried to obtain an iron supplement compound.

[0047] Comparative Example 3 Different from Example 1, a double-layer structure was not prepared in this comparative example.

[0048] The preparation method of the iron supplement compound comprises the following specific steps: Preparation of core layer solution: 10 g of iron protein succinate was added to 100 mL of purified water and dispersed at 8000 rpm for 10 min to obtain a dispersed solution. 4% lysine solution was prepared using lysine and purified water.

[0049] 20 mL of 4% lysine solution was added to the dispersed solution, ultrasonically treated at 300 W for 3 min, and the pH was adjusted to 6.5 to obtain an amino acid solution.

[0050] Separation: Centrifuge the amino acid solution at 5000 rpm for 10 min, collect the precipitate, wash it twice with purified water, and dry it to obtain the iron supplement compound.

[0051] Detection: In vitro release test: 20 mg of the iron supplement compound samples of Examples 1-3 and Comparative Examples 1-3 were weighed and placed in different simulated liquids, which were simulated gastric fluid and simulated intestinal fluid.

[0052] Specifically: 1. Prepare simulated fluid: simulated gastric fluid: take 16.4 mL of dilute hydrochloric acid, add 800 mL of water and 10 g of pepsin, shake well, dilute with water to 1000 mL, adjust the pH to 1.2, and obtain simulated gastric fluid.

[0053] Simulated intestinal fluid: Take 6.8g of potassium dihydrogen phosphate, add 500ml of water to dissolve it, and adjust the pH value to 6.8 with 0.1mol / L sodium hydroxide solution; take another 10g of pancreatic enzyme, add appropriate amount of water to dissolve it, mix the two liquids, and dilute with water to 1000ml to obtain simulated intestinal fluid.

[0054] 2. Place the iron-supplementing compound sample into a dialysis bag and seal the two ends of the dialysis bag with clips. Note: The dialysis bag needs to be soaked in purified water for 12 hours in advance to remove the protective agent.

[0055] 3. The first stage (simulated gastric fluid release): under the following conditions, place the dialysis bag in 100 mL of simulated gastric fluid, place in a constant temperature water bath at 37±0.5℃ and 100 rpm, and start timing. Take out 2 mL of simulated fluid as the release fluid at 0.5 hour, 1 hour, and 2 hours, add an equal amount of fresh simulated gastric fluid, and record the sampling time. Continue to release for 2 hours, and end the gastric fluid release stage.

[0056] Phase II (simulated intestinal fluid release): The dialysis bag was removed from the gastric fluid, rinsed with purified water, and transferred to 100 mL of simulated intestinal fluid. 2 mL of simulated fluid was taken out as release fluid at 4 hours, 6 hours, 8 hours, 12 hours, and 24 hours, and an equal amount of fresh simulated intestinal fluid was added, and the sampling time was recorded.

[0057] Storage of release solution: Each sample of release solution should be immediately centrifuged at 10,000 rpm for 10 minutes, and the supernatant should be stored at 4°C for testing.

[0058] 4. Determination of iron content: prepare 0.0167 mol / L potassium dichromate standard solution, place the release solution to be tested in the reaction bottle, add water to make up to 10 mL, take 5 mL of the diluted release solution into a conical flask, add 5 mL of concentrated sulfuric acid and 2 mL of concentrated phosphoric acid, add 1-2 drops of diphenylamine indicator, and titrate with potassium dichromate standard solution until the solution changes color, record the volume of potassium dichromate consumed, and calculate the iron content.

[0059] The calculation formula / process is: Step (1): Calculate the mass concentration of iron in the release solution (ρ Fe ), in mg / mL: ρ Fe = (V 标准 ×C 标准 ×M Fe ) / (V 样品 ×f) in: V 标准 : The volume of potassium dichromate standard solution consumed in titration, in mL; C 标准 : The concentration of potassium dichromate standard solution, in mol / L, which is 0.0167 mol / L in this experiment; M Fe : The molar mass of iron, 55.845 g / mol was used in this experiment; V 样品 : The volume of the release solution taken after dilution, in mL, which is 5 mL in this experiment; f: dilution factor of the release solution, which is 10mL / 5mL=2 in this experiment; Step (2): Calculate the mass of iron released at each time point (m Fe ), unit is mg: m Fe =ρ Fe ×V 释放液 in: ρ Fe : The mass concentration of iron in the release solution, in mg / mL (calculated in step (1)); V 释放液 : The volume of the released liquid, in mL, which is 2 mL in this experiment (the volume of each sampling); Step (3): Calculate the cumulative release amount (Q n ), unit is mg: For the first time point (n=1): Q1=m Fe1 For subsequent time points (n>1): Q n =m Fen +Σ n-1 i=1 (mFe i ×V 取样 / V 总体积 ) in: m Fen : The mass of iron released at the nth time point, in mg (calculated by step (2)); m Fei : The mass of iron released at the i-th time point, in mg (calculated by step (2)); V取样 : The volume of each sample, in mL, which is 2 mL in this experiment; V 总体积 : The total volume of the simulated liquid, in mL, which is 100 mL in this experiment; Step (4): Calculate the cumulative release percentage (%) at each time point: Cumulative release percentage (%) = (Q n / m 总Fe )×100% in: Q n : Cumulative release amount at the nth time point, in mg (calculated by step (3)); m 总Fe : The total mass of iron in the sample, in mg. In this experiment, the sample mass is 20 mg, and m needs to be calculated based on the iron content of protein succinate iron. 总Fe In this application, the iron content of protein succinate is 5%, then m 总Fe =20mg×5%=1mg.

[0060] The results are shown in Table 1 below: Table 1

[0061] analyze: (1) Comparison of sustained-release performance: Gastric phase (0-2 hours): Example 1-3: Since the combination of lysine / glutamic acid and chitosan enhances the stability of the core layer and the coating layer, the iron ion release is slower and the cumulative release amount is expected to be lower than that of Comparative Example 1-3.

[0062] Comparative Example 1: Lacking the stabilizing effect of amino acids, the iron in the core layer is released faster.

[0063] Comparative Example 2: There is no nano-silicon dioxide to increase the density of the shell layer, the coating layer structure is looser, and the iron release is higher.

[0064] Comparative Example 3: Although Comparative Example 3 contains lysine, it is rapidly released in the simulated liquid due to the lack of coating protection, which further illustrates that lysine chelation requires the synergistic effect of the coating layer to achieve sustained release.

[0065] Intestinal fluid phase (4-24 hours): Example 1-3: The carboxymethyl chitosan of the coating layer provides a sustained-release skeleton, and nano-silicon dioxide enhances the density of the shell layer, so that the iron release is more stable.

[0066] Comparative Example 1: Lack of amino acids, rapid release of iron ions, poor sustained-release performance.

[0067] Comparative Example 2: The density of the coating layer is insufficient, and the iron release rate is faster, but slightly slower than that of Comparative Example 1.

[0068] Comparative Example 3: Iron ions were almost completely released in the simulated gastric fluid, and the remaining iron ions were continuously released in the simulated intestinal fluid. Moreover, due to the absence of a coating structure, the release was rapid and there was no sustained-release effect.

[0069] (2) Comparison between embodiments: Example 2 (glutamic acid replacing lysine): The sustained release effect of Example 2 is inferior to that of Example 1. It can be seen that in the technical scheme of the present application, the chelating ability of glutamic acid is slightly weaker than that of lysine, the stability to iron ions is slightly lower, and the release rate is slightly faster than that of Example 1.

[0070] Example 3 (3% carboxymethyl chitosan replacing 2% solution): The increase in carboxymethyl chitosan concentration resulted in an increase in the coating thickness and a further decrease in the iron release rate, showing a better sustained-release performance.

[0071] In general: the components form a synergistic effect. Lysine / glutamic acid in the core layer stabilizes iron ions through chelation; carboxymethyl chitosan in the coating layer provides a sustained-release skeleton, forming a uniform and dense coating structure with lecithin and glycerol; nano-silicon dioxide further optimizes the performance of the coating layer. This multiple action mechanism and pH sensitivity of the double-layer structure ensure a good sustained-release effect of iron, avoid rapid release in the stomach, and achieve sustained release in the intestine, which is beneficial to improve the bioavailability of iron, avoid excessive release of free iron ions, and reduce side effects.

[0072] The iron-supplementing compound prepared by the present invention can produce the above-mentioned technical effects, but it does not mean that it can be directly put into use. The present invention can lay a foundation for subsequent further development experiments and verification tests as well as experiments for putting it into use.

[0073] It should be noted that the raw materials used in the above-mentioned process include: Iron protein succinate: Shanghai McLean Biochemical Technology Co., Ltd., 98% purity, 5% iron content, pharmaceutical grade.

[0074] Lysine: Lysine hydrochloride, Sigma-Aldrich, 98% purity, pharmaceutical grade.

[0075] Lecithin: Soy lecithin, Meggle from Germany, 95% phospholipid content, food grade.

[0076] Carboxymethyl chitosan: Aladdin reagent, viscosity 100-200mPa.s, food grade.

[0077] Nano-silicon dioxide: Evonik, Germany, particle size: 12nm, food grade.

[0078] Glutamic acid: L-glutamic acid.

[0079] Unless otherwise specified, the purity of raw materials or materials should be 99%, medicinal grade or food grade.

[0080] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A method for preparing a sustained-release iron supplement compound, characterized in that: The steps include: The iron salt is dispersed in a solvent to obtain a dispersed solution, and amino acids are added to the dispersed solution to obtain an amino acid solution; The lecithin and the polyol are mixed and homogenized to obtain an emulsion, chitosan is added dropwise to the emulsion, and stirred to obtain a polysaccharide solution; The amino acid solution is added dropwise to the polysaccharide solution, stirred, and an inorganic filler is added to obtain a composite solution; The complex solution is centrifuged, and the precipitate is collected to obtain a sustained-release iron supplement compound.

2. The method for preparing the sustained-release iron supplement compound according to claim 1, characterized in that: The amino acid includes at least one of lysine and glutamic acid.

3. The method for preparing the sustained-release iron supplement compound according to claim 1, characterized in that: The chitosan includes at least one of carboxymethyl chitosan and sodium alginate.

4. The method for preparing the sustained-release iron supplement compound according to claim 1, characterized in that: Polyols include glycerol.

5. The method for preparing the sustained-release iron supplement compound according to claim 1, characterized in that: The chitosan is a chitosan solution, and the concentration of the chitosan solution is 1-5%.

6. The method for preparing the sustained-release iron supplement compound according to claim 1, characterized in that: When the amino acid is added to the dispersed solution, the concentration of the amino acid is 1-5%.

7. The method for preparing the sustained-release iron supplement compound according to claim 1, characterized in that: The polyol is a polyol aqueous solution, and the volume ratio of the polyol to water is 1-5:5-7.

8. The method for preparing the sustained-release iron supplement compound according to claim 1, characterized in that: The iron salt includes at least one of ferric protein succinate, ferric citrate and ferrous lactate.

9. The method for preparing the sustained-release iron supplement compound according to claim 1, characterized in that: The inorganic filler includes silicon dioxide, and silicon dioxide includes nano silicon dioxide.

10. A sustained-release iron supplement compound, characterized in that: The sustained-release iron-supplementing compound is prepared according to the preparation method of the sustained-release iron-supplementing compound according to claims 1-9.

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