CN109172523B

CN109172523B - Self-microemulsion of amygdalin, and preparation method thereof

Info

Publication number: CN109172523B
Application number: CN201811305393.1A
Authority: CN
Inventors: 樊丽雅; 周红兵; 张璐; 郑春丽
Original assignee: Inner mongolia university of science and technology baotou medical college
Current assignee: Inner mongolia university of science and technology baotou medical college
Priority date: 2018-11-05
Filing date: 2018-11-05
Publication date: 2020-10-23
Anticipated expiration: 2038-11-05
Also published as: CN109172523A

Abstract

The invention relates to the field of medicinal preparations, and provides a self-microemulsion of amygdalin, a preparation formulation prepared from the same and a preparation method of the self-microemulsion. The self-microemulsion of amygdalin comprises amygdalin, an oil phase, an emulsifier and a co-emulsifier, wherein the weight ratio of the oil phase to the emulsifier to the co-emulsifier is (20-75) to (25-60) to (0.1-30). The self-microemulsion has the advantages of high drug loading, stable quality, narrow and uniform particle size distribution, greatly improved membrane penetration rate of the drug, capability of enabling the drug to finally reach a focus, better treatment effect and wide application prospect.

Description

Self-microemulsion of amygdalin, and preparation method thereof

Technical Field

The invention relates to the field of pharmaceutical preparations, in particular to a self-microemulsion preparation.

Background

Compared with the common microemulsion, the self-microemulsion is a liquid preparation with stable property, which is composed of an oil phase, an emulsifier, an auxiliary emulsifier and a medicament according to a specific proportion, and the self-microemulsion and digestive juice can spontaneously form an O/W emulsion under a certain condition. It is advantageous to increase the water solubility of lipophilic drugs; the stability of the medicine is improved; increasing the bioavailability of the oral drug; meanwhile, the medicine is wrapped in the oil phase, and the medicine in the external water phase is less, so that irritation and potential toxicity caused by local overlarge medicine concentration can be effectively avoided.

Amygdalin is a pharmacologically active component of amygdalin, and is a beta-type glycoside composed of gentiobiose and amygdaline. Since amygdalin has various pharmacological actions such as relieving cough and asthma, and resisting cancer, it has become a common cough relieving agent and an auxiliary anticancer drug at present. The molecular structure is shown as a formula I.

Amygdalin has good water solubility and poor fat solubility, so the amygdalin has poor membrane permeability, and the compatibility of the amygdalin and a biological membrane is low, most of the medicines are mainly concentrated in the gastrointestinal tract, have strong local stimulation to the gastrointestinal tract, and cannot penetrate through a cell membrane to reach a focus. At present, preparations prepared by independently researching amygdalin comprise gels and gelatin microspheres, but the gels are easy to decay and need to be added with preservatives; the gelatin microspheres are easy to crosslink and have poor quality controllability. In addition, amygdalin is still mainly present in compound preparations, but it is not favorable for making personalized treatment schemes according to different patient conditions.

Disclosure of Invention

In order to overcome the technical problems, the invention originally combines the physicochemical properties of amygdalin with self-microemulsion type, and prepares the amygdalin self-microemulsion with high drug loading, stable quality, narrow and uniform particle size distribution by selecting proper oil phase, emulsifier and auxiliary emulsifier, thereby greatly improving the membrane penetration rate of the drug, leading the drug to finally reach the focus and playing a better treatment effect.

In order to achieve the purpose, the invention adopts the following technical scheme:

in one aspect, the invention provides a self-microemulsion of amygdalin, which is characterized in that the self-microemulsion comprises amygdalin, an oil phase, an emulsifier and a co-emulsifier.

Furthermore, the weight ratio of the oil phase, the emulsifier and the co-emulsifier in the self-microemulsion is (20-75) to (25-60) to (0.1-30); preferably, the weight ratio of the oil phase, the emulsifier and the co-emulsifier in the self-microemulsion is (35-50) to (30-50) to (5-20); preferably, the weight ratio of the oil phase, the emulsifier and the co-emulsifier in the self-microemulsion is (40-45) to (10-15); more preferably, the weight ratio of the oil phase, the emulsifier and the co-emulsifier in the self-microemulsion is 45: 41.25: 13.75.

Further, the content of amygdalin in the self-microemulsion is less than 20 mg/mL; preferably, the content of amygdalin in the self-microemulsion is (0.1-15) mg/mL; preferably, the content of amygdalin in the self-microemulsion is less than (1-12) mg/mL; preferably, the content of amygdalin in the self-microemulsion is (2-9) mg/mL; preferably, the content of amygdalin in the self-microemulsion is (3-7) mg/mL; preferably, the content of amygdalin in the self-microemulsion is (4-6) mg/mL; more preferably, the content of amygdalin in the self-microemulsion is 6 mg/mL.

Further, the oil phase is selected from one or more of Medium Chain Triglyceride (MCT), oleic acid, castor oil, propylene glycol monocaprylate (Capryol), glycerol monolinoleate (Maisine), glycerol monooleate (Peceol), polyethylene glycol-6-oleate (Labrafil) and ethyl oleate. Preferably, the oil phase is selected from a mixture of ethyl oleate and one or more of medium-chain triglyceride, oleic acid, castor oil, propylene glycol monocaprylate, glycerol monolinoleate, glycerol monooleate and polyethylene glycol-6-oleate; or the oil phase is selected from one or more of glycerol monooleate, medium chain triglyceride, oleic acid, castor oil, propylene glycol monocaprylate, glycerol monolinoleate, polyethylene glycol-6-oleate and ethyl oleate. Preferably, the dosage ratio of the ethyl oleate to other components in the oil phase mixture is (1-10): (1-10), and most preferably 1: 1; more preferably, the dosage ratio of the glyceryl monooleate to other components in the oil phase mixture is (1-10) to (1-10), and most preferably 1: 1. Still more preferably, the oil phase is selected from the group consisting of mixtures of ethyl oleate and medium chain triglycerides; or the oil phase is selected from a mixture of glycerol monooleate and medium chain triglycerides; preferably, the dosage ratio of the ethyl oleate to the medium-chain triglyceride in the oil phase mixture is (1-10): (1-10), and most preferably 1: 1; more preferably, the dosage ratio of the glyceryl monooleate to the medium chain triglyceride in the oil phase mixture is (1-10): (1-10), and most preferably 1: 1.

Further, the emulsifier is selected from one or more of polyoxyethylene hydrogenated castor oil (Cremophor), polyoxyethylene castor oil, tween-80, tween-20, emulsifier OP, caprylic capric acid polyethylene glycol glyceride (Labrasol), lauric acid polyethylene glycol-32 glyceride (glucire), Span-80 (Span-80) and isopropyl myristate. Preferably, the emulsifier is selected from one or more of emulsifier OP, caprylic capric acid polyethylene glycol glyceride and lauric acid polyethylene glycol-32 glyceride.

Further, the coemulsifier is one or more selected from 1, 2-propylene glycol, glycerol, polyethylene glycol 400, polyethylene glycol 200, isopropanol, ethanol, ethylene glycol and ethylene glycol monoethyl ether (Transcutol). Preferably, the coemulsifier is selected from one or more of 1, 2-propylene glycol and polyethylene glycol 400.

Further, the particle size of the self-microemulsion is 50-500 nm; preferably, the particle size of the self-microemulsion is 80-200 nm; preferably, the particle size of the self-microemulsion is 100-150 nm; most preferably, the particle size of the self-microemulsion is (113.3 ± 0.8) nm.

In a second aspect, the invention provides a dosage form of amygdalin prepared from a microemulsion.

Further, the dosage form is selected from oral dosage forms, injection dosage forms, inhalation dosage forms or transdermal administration dosage forms. Preferably, the dosage form is selected from the group consisting of tablets, capsules, granules, solid dispersions, injections, liposomes, microspheres, sprays, inhalants, emulsions or patches.

Further, the preparation comprises the self-microemulsion of the amygdalin and one or more medicinal auxiliary materials. Preferably, the pharmaceutically acceptable adjuvant is selected from one or more of fillers, binders, wetting agents, disintegrating agents, surfactants, adsorption carriers, lubricants, injection solvents, buffers, bacteriostats, local anesthetics, isotonic adjusting agents, suspending agents, protecting agents, emulsifying agents, matrixes, pigments, flavoring agents, sweetening agents, solubilizing agents and absorption enhancers.

In a third aspect, the invention provides a preparation method of self-microemulsion of amygdalin.

Further, the preparation method comprises the following steps: adding amygdalin into oil phase, emulsifier and auxiliary emulsifier, and performing ultrasonic treatment, shaking and filtering.

Further, the preparation method comprises the following steps: weighing the oil phase, the emulsifier and the co-emulsifier according to the formula amount, adding the amygdalin according to the formula amount, carrying out ultrasonic treatment for 20-50 min, placing in a constant-temperature water bath oscillator at 20-40 ℃ for oscillation for 12-36 h, filtering supernate with a microporous filter membrane, and discarding primary filtrate.

Further, the preparation method comprises the following steps: weighing the oil phase, the emulsifier and the coemulsifier according to the prescription amount, adding the amygdalin according to the prescription amount, carrying out ultrasonic treatment for 30min, placing in a constant-temperature water bath oscillator at 37 ℃ for shaking for 24h, filtering supernate with a 0.22 mu m microporous filter membrane, and discarding the primary filtrate.

Compared with the prior art, the invention has the following beneficial effects:

the amygdalin provided by the invention has the advantages of high self-microemulsion drug loading, stable quality, narrow and uniform particle size distribution, greatly improves the membrane penetration rate of the drug, enables the drug to finally reach the focus and plays a better treatment effect. Wherein the saturation solubility of the amygdalin in the blank self-microemulsion is 12.65 mg/mL; the particle size polydispersity is (0.171. + -. 0.007); no layering phenomenon after centrifugation, and excellent standing stability, dilution stability and storage life. The invention also provides a preparation formulation prepared from the self-microemulsion of amygdalin and a preparation method, and the preparation formulation has wide application prospect.

Drawings

FIG. 1 is a graph of the UV scan of amygdalin in methanol.

FIG. 2 is a graph of the UV scan of amygdalin in methanol/water (25: 75).

FIG. 3 is a liquid chromatogram of amygdalin.

Fig. 4 is a standard curve of amygdalin (n ═ 3).

Fig. 5 is the equilibrium solubility of amygdalin in different oil phases (n ═ 3), where indicates a significant difference in solubility (p <0.05) compared to "glycerol monolinoleate"; indicates a very significant difference in solubility (p <0.01) compared to "glycerol monolinoleate".

Figure 6 is the equilibrium solubility of amygdalin in different emulsifiers (n ═ 3), where indicates a significant difference in solubility compared to "tween 80" (p < 0.05); indicates a very significant difference in solubility compared to "tween 80" (p < 0.01).

Figure 7 is the equilibrium solubility of amygdalin in different coemulsifiers (n ═ 3), where indicates a significant difference in solubility (p <0.05) compared to "isopropanol"; indicates a very significant difference in solubility compared to "isopropanol" (p < 0.01).

FIG. 8 is a pseudo-ternary phase diagram of (A) Peceol/MCT-OP-1, 2-propandiol and (B) Peceo/MCTl-OP-PEG 400 blank self-microemulsions.

Fig. 9 shows the particle size (n-3) of the blank self-microemulsion at different oil phase ratios.

Fig. 10 is the particle size (n-3) of different Km blanks from microemulsion.

Fig. 11 shows the particle size variation (n-3) for different drug loadings from the microemulsion formulation.

FIG. 12 is the appearance of (A) amygdalin self-microemulsion and (B) amygdalin self-microemulsion after self-emulsification.

Detailed Description

The technical solutions of the present invention are further illustrated by the following specific embodiments, but it is easily understood by those skilled in the art that the specific material ratios, process conditions and results thereof described in the examples are only for illustrating the present invention, and should not also limit the present invention described in detail in the claims.

Example 1 establishment of amygdalin assay

1. Determination of detection wavelength

Precisely weighing 10mg of amygdalin, placing into a 10mL volumetric flask, respectively adding appropriate amount of pure methanol and methanol-water (25:75), dissolving, fixing volume to scale, shaking, and determining the maximum absorption wavelength of amygdalin by ultraviolet scanning. The maximum absorption wavelength with pure methanol as solvent is 209nm, as shown in FIG. 1. The maximum absorption wavelength was 205nm using methanol-water (25:75) as the solvent, as shown in FIG. 2. According to the spectrogram of the amygdalin ultraviolet scanning spectrum, the maximum absorption wavelength is about 210nm, and if the ultraviolet spectrophotometry is selected for the content determination of the amygdalin, the interference of the auxiliary materials and the solvent to the determination result is large, so the HPLC is finally selected for the content determination of the amygdalin.

2. High performance liquid chromatography conditions

A chromatographic column: unitry C18 column (4.6 mm. times.250 mm, 5 μm, Wasp. New science and technology Co., Ltd.)

Mobile phase: methanol-water (25:75, v/v)

Column temperature: 35 deg.C

Flow rate: 1mL/min

A detector: UVD

Detection wavelength: 210nm

Sample introduction amount: 20 μ L

3. Chromatographic Condition System Adaptation test

Precisely weighing amygdalin 20mg, placing in a 50mL volumetric flask, dissolving with 50% methanol, fixing the volume to the scale, and shaking to obtain amygdalin stock solution. Precisely sucking 4mL of the amygdalin stock solution, placing the amygdalin stock solution into a 10mL volumetric flask, diluting with 25% methanol (mobile phase), fixing the volume to a scale, and shaking up. Taking a proper amount of the solution in a centrifuge tube, centrifuging for 10min at the rotating speed of 12000rpm, sucking 20 mu L of supernatant, injecting sample for three times, recording chromatogram, and calculating the number of theoretical plates and the separation degree. The theoretical plate number is required to be not less than 3500, and the separation degree is required to be more than 1.5.

The amygdalin liquid chromatogram is shown in FIG. 3. The theoretical plate number (n) is 6598, and the result shows that the theoretical plate number meets the requirement (n is more than 3500); the degree of separation (R) was 21.1, and the results showed that the degree of separation satisfied the requirement (R > 1.5).

4. Drawing of standard curve

Precisely sucking 1mL, 2mL, 3mL, 4mL and 5mL of the amygdalin stock solution, placing in a 10mL volumetric flask, dissolving with 25% methanol, fixing the volume to the scale, and shaking up to obtain standard amygdalin solutions with the concentrations of 0.04mg/mL, 0.08mg/mL, 0.12mg/mL, 0.16mg/mL and 0.20mg/mL respectively. Taking a proper amount of standard solution in a centrifuge tube, centrifuging for 10min at the rotation speed of 12000rpm, sucking the supernatant, injecting sample for three times respectively at 20 mu L, recording peak area, taking the concentration (C) and the peak area (A) of the amygdalin as the horizontal and vertical coordinates of the standard curve respectively, performing linear regression, and drawing to obtain the amygdalin standard curve.

Standard curve equation for amygdalin: a-15338C-51256 (R2-0.9997) at a concentration in the range of 40 μ g/mL to 200 μ g/mL, with good linearity, the linear plot being shown in fig. 4.

5. Determination of precision

Precisely sucking 3mL of the amygdalin stock solution, placing the amygdalin stock solution into a 10mL volumetric flask, dissolving the amygdalin stock solution by using 25% methanol, fixing the volume to a scale, shaking up, taking a proper amount of standard solution in a centrifuge tube, centrifuging the solution for 10min at the rotating speed of 12000rpm, sucking 20 mu L of supernatant liquid respectively, injecting the sample for five times, recording peak areas, substituting the peak areas into an amygdalin standard curve equation for calculation to obtain the measured concentration, and calculating the precision, wherein the measured concentration cannot be more than 2% as represented by the relative standard deviation RSD (%) of.

The results of the precision determination of the amygdalin solution are shown in Table 1. As can be seen from the results in Table 1, the daily RSD of the amygdalin solution is less than 2%, which indicates that the method has good precision and is stable and reliable.

Precision of the method (n ═ 5) in Table 1

6. Determination of recovery

Precisely sucking 1.5mL, 3mL and 5mL of amygdalin stock solution, placing the amygdalin stock solution into a 10mL volumetric flask, dissolving the amygdalin stock solution by using 25% methanol, fixing the volume to a scale, shaking up, respectively preparing 0.04mg/mL (low concentration), 0.12mg/mL (medium concentration) and 0.2mg/mL (high concentration) amygdalin standard solutions, taking a proper amount of standard solutions into a centrifuge tube, centrifuging for 10min at the rotating speed of 12000rpm, sucking 20 mu L of supernatant, injecting samples for three times, recording peak areas, substituting into an amygdalin standard curve equation for calculation to obtain the measured concentration, and obtaining the recovery rate by measuring the ratio of the concentration to the actual concentration. The specified recovery rate is between 98% and 102%.

The results of the recovery of the drug in the samples at the low, medium and high concentrations are shown in Table 2. As can be seen from Table 2, the recovery rates of the low, medium and high concentrations are between 98% and 102%, and the RSD value is less than 2%, which shows that the recovery rate of the method is qualified and the accuracy is good.

Table 2 recovery rate of process (n ═ 3)

EXAMPLE 2 determination of the oil-Water partition coefficient of amygdalin

The oil-water distribution coefficient of amygdalin is determined by a classical shake flask method. Respectively measuring 100mL of deionized water and 100mL of n-octanol into a separating funnel, shaking the volumetric flask to fully mix the solution, standing at room temperature for 24 hours, wherein the lower layer is a saturated aqueous solution of the n-octanol, and the upper layer is a saturated aqueous solution of the n-octanol. Adding excessive amygdalin into n-octanol saturated water solution, shaking in 37 deg.C water bath for 24h to obtain amygdalin saturated solution, filtering with 0.22 μm microporous membrane, discarding the initial filtrate, collecting the subsequent filtrate, precisely measuring 5mL of the subsequent filtrate, mixing with water saturated n-octanol solution with equal volume, vortexing for 3min, standing in 37 deg.C water bath for 24h, respectively sucking water layer and n-octanol layer 100 μ L to 10mL volumetric flasks, diluting with 25% methanol to scale, shaking the volumetric flasks to mix the solutions thoroughly, sucking the above solutions 20 μ L, sampling, recording peak area three times, substituting into amygdalin standard curve equation to obtain amygdalin solubility Cw in water phase and amygdalin solubility Co in organic phase, and calculating oil-water distribution coefficient according to formula P ═ Cw.

The determination result of the oil-water distribution coefficient of amygdalin is as follows:

P＝0.026

LogP＝-1.58

the result shows that the oil-water distribution coefficient of the amygdalin is low, which indicates that the amygdalin has poor lipid solubility and is difficult to prepare self-microemulsion, and the amygdalin self-microemulsion with certain drug-loading rate can be prepared only by selecting proper oil phase, emulsifier and auxiliary emulsifier.

Example 3 determination of equilibrium solubility of amygdalin in different media

1. Determination of equilibrium solubility of amygdalin in different oil phases

About 5mL of Medium Chain Triglyceride (MCT), oleic acid, castor oil, and propylene glycol monocaprylate were takenEsters (Capryol)^TM90) Glycerol monolinoleate (Maisine)^TM35-1), glycerol monooleate (Peceol)^TM) Oleic acid polyethylene glycol-6 glyceride (

M1944CS), placing ethyl oleate into a test tube with a plug, adding excessive amygdalin, performing ultrasonic treatment for 30min, placing into a constant-temperature water bath oscillator at 37 ℃ and shaking for 24h, filtering the supernatant with a 0.22 mu M microporous filter membrane, discarding the primary filtrate, collecting the secondary filtrate, transferring the secondary filtrate with a pipette into a volumetric flask with the volume of 100 mu L to 10mL, diluting with pure methanol to the scale, shaking the volumetric flask to fully mix the solution, respectively sucking 20 mu L of the solution, injecting, recording the peak area, and substituting into the standard curve equation of amygdalin for calculation. Measuring each oil phase for 3 times, averaging, and screening oil phase with good solubility to amygdalin.

The equilibrium solubility of amygdalin in different oil phases, as shown in fig. 5, from high to low, is: ethyl oleate, Peceol, castor oil, oleic acid, MCT, Labrafil M1944CS, Capryol 90, Maisine 35-1.

2. Determination of equilibrium solubility of amygdalin in different emulsifiers

Respectively taking about 2m L polyoxyethylene hydrogenated castor oil (

RH-40), polyoxyethylated castor oil (

EL35), tween-80, tween-20, emulsifier OP, caprylic capric acid polyethylene glycol glyceride

Lauric acid polyethylene glycol-32 glyceride (glucire)^TM44/14) placing in a test tube with a plug, adding excessive amygdalin, performing ultrasonic treatment for 30min, placing in a constant temperature water bath oscillator at 37 deg.C, shaking for 24 hr, filtering the supernatant with 0.22 μm microporous membrane, discarding the primary filtrate, collecting the secondary filtrate, transferring the secondary filtrate with a pipette into a volumetric flask of 100 μ L to 10mL, diluting with pure methanolAnd (4) shaking the volumetric flask to fully mix the solution, respectively sucking 20 mu L of the solution, injecting the sample, recording the peak area, and substituting the peak area into the standard curve equation of amygdalin for calculation. Each emulsifier is measured for 3 times, the average value is calculated, and the emulsifier which is better to dissolve the amygdalin is screened.

The equilibrium solubility of amygdalin in different emulsifiers, as shown in fig. 6, from high to low, is as follows: emulsifier OP, Laibasol, Gelucire 44/41, Cremophor EL35, Cremophor RH40, Tween-20 and Tween-80.

3. Determination of equilibrium solubility of amygdalin in different coemulsifiers

About 2mL of 1,2-propanediol, glycerol, polyethylene glycol 400, isopropanol, ethanol, and ethylene glycol monoethyl ether(s) ((R))

HP) is placed in a test tube with a plug, excessive amygdalin is added, ultrasonic treatment is carried out for 30min, the test tube is placed in a constant-temperature water bath oscillator with the temperature of 37 ℃ to vibrate for 24h, supernatant is filtered by a millipore filter with the diameter of 0.22 mu m, primary filtrate is discarded, continuous filtrate is collected, 100 mu L to 10mL of continuous filtrate is moved by a pipette, pure methanol is used for diluting to the scale, the volumetric flask is shaken to fully mix the solution, each 20 mu L of the solution is respectively absorbed for sample injection, peak area is recorded and substituted into the standard curve equation of the amygdalin for calculation. Each co-emulsifier is determined for 3 times, the average value is calculated, and the co-emulsifier which is better in dissolving the amygdalin is screened.

The equilibrium solubility of amygdalin in different coemulsifiers, as shown in fig. 7, from high to low, is as follows: 1, 2-propylene glycol, PEG 400, glycerol, Transcutol HP, ethanol and isopropanol.

EXAMPLE 4 compatibility variation of different oil phases, emulsifiers, Co-emulsifiers

And selecting an oil phase, an emulsifier and a co-emulsifier which have better dissolving capacity for amygdalin according to a balanced solubility test, and carrying out a next experiment to investigate the compatibility change of different oil phases, emulsifiers and co-emulsifiers. Mixing oil phase, emulsifier and co-emulsifier at a mass ratio of 2:2:1, diluting with deionized water 100 times, magnetically stirring at 37 deg.C, observing self-emulsifying degree by visual method, and recording self-emulsifying time. The self-emulsification was classified into 6 grades: the solution is clear and transparent and has blue opalescence (A); the solution is semitransparent and has blue opalescence (B); the solution was milky white (C); the solution was off-white (D); carrying oil droplets (E); and (F) layering. And screening a prescription with good self-emulsifying condition.

The emulsifying conditions of the self-emulsifying preparation after the oil phase to be selected, namely the ethyl oleate and the Peceol, the emulsifier to be selected, namely the emulsifier OP, the Laibastrol and the Gelucire 44/41, and the auxiliary emulsifying 1, 2-propylene glycol and the PEG 400 are matched are shown in table 3.

TABLE 3 self-emulsification of different oil phase, emulsifier, co-emulsifier systems

Selecting ethyl oleate: medium chain triglycerides MCT (1:1) and glycerol monooleate Peceol: the emulsification of the self-emulsifying formulation after medium chain triglyceride MCT (1:1) was used as the oil blend phase is shown in Table 4. As can be seen from table 4, ethyl oleate was selected: MCT (1:1) and Peceol: MCT (1:1) is better emulsified in the self-emulsifying preparation after being used as a mixed oil phase. The final choice of the system Peceol/MCT, depending on the emulsification of the self-emulsifying formulation: emulsifier OP: 1,2-propanediol and system Peceo/MCTL: emulsifier OP: PEG 400 was subjected to the next study.

TABLE 4 self-emulsification of different mixed oil phase, emulsifier, co-emulsifier systems

Example 5 drawing of pseudo ternary phase diagram

In the self-emulsifying preparation formula, the oil phase accounts for 25-70%, the emulsifier accounts for more than 25% and the co-emulsifier accounts for 0-25%, the proportion of the oil phase, the emulsifier and the co-emulsifier is changed, the components in different proportions are weighed, the mixture is swirled for 3min and uniformly mixed, 100 mu L of the self-emulsifying preparation is absorbed and added into 10mL of deionized water, magnetic stirring is carried out at 37 ℃, after the self-emulsification is completed, the appearance of the solution is observed, the transparent or semitransparent and blue opalescent formula is recorded, a pseudo-ternary phase diagram is drawn by taking the mass ratio of the oil phase, the emulsifier and the co-emulsifier as three variables, and a system with a larger area is selected as the optimal formula. The results are shown in FIG. 8.

As can be seen from FIG. 8, the ratio of Peceol/MCT (1: 1): emulsifier OP: 1, 2-propylene glycol is a blank self-microemulsion system, and the area of an emulsification area formed in a pseudo-ternary phase diagram is large, so Peceol/MCT (1: 1): emulsifier OP: the 1,2-propanediol system was further investigated.

EXAMPLE 6 Single factor Experimental review of SEDDS prescription

1. Screening of oil phase ratio

Fixing the mass ratio of the emulsifier to the co-emulsifier (Km is 2:1), changing the proportion of the oil phase between 20% and 75% (w/w), preparing a self-emulsifying preparation, diluting by a certain multiple, measuring the particle size of the self-emulsifying preparation after emulsification, and screening out the optimal proportion of the oil phase.

Preparing self-microemulsion preparations according to different proportions of oil phase, emulsifying, and layering the self-microemulsion preparations after emulsification when the proportion of the oil phase is 70% (w/w) and 75% (w/w), wherein the rest particle diameters are shown in figure 9. As can be seen from fig. 9, the particle size gradually increased with the increase in the oil phase ratio. The oil phase was finally selected to have a ratio of 45% (w/w) in combination with the particle size and particle size distribution.

2. Screening of emulsifier to co-emulsifier ratio

Fixing the oil phase proportion to 45% (w/w), setting the mass ratio of the emulsifier to the co-emulsifier to be 1:2, 1:1, 1.5:1, 2:1, 2.5:1, 3:1 and 4:1 respectively, preparing the self-emulsifying preparation, diluting by a certain multiple, measuring the particle size of the self-emulsifying preparation after emulsification, and screening out the optimal mass ratio of the emulsifier to the co-emulsifier.

Self-emulsifying formulations were prepared at different Km and after emulsification the particle size is shown in FIG. 10. As can be seen from fig. 10, as Km increases, the particle size decreases first and then increases, and when Km is 3:1, the measured particle size is the smallest, indicating that the compatibility of the system is best at this time, and therefore Km is finally determined to be 3: 1.

Example 7 determination of drug Loading

1. Determination of saturation solubility of amygdalin in blank self-microemulsion

Preparing blank self-microemulsion according to an optimal formula, placing the blank self-microemulsion in a test tube with a plug, adding excessive amygdalin, carrying out ultrasonic treatment for 30min, placing the test tube in a constant-temperature water bath oscillator at 37 ℃ and shaking for 24h, filtering supernatant by using a 0.22 mu m microporous filter membrane, discarding primary filtrate, collecting secondary filtrate, transferring 100 mu L to 10mL volumetric flask of the secondary filtrate by using a pipette, diluting the secondary filtrate to a scale by using pure methanol, shaking the volumetric flask to fully mix the solution, sucking 20 mu L of the solution, injecting the sample, recording peak area, substituting the peak area into an amygdalin standard curve equation for calculation, and obtaining the saturation solubility of the amygdalin in the blank self-microemulsion. The total number of measurements was 3 times, and the average value was determined. The measurement result shows that the saturation solubility of the amygdalin in the blank self-microemulsion is 12.65 mg/mL.

2. Determination of drug loading

Preparing blank self-microemulsion 1mL according to the optimal prescription, adding 8 parts, respectively adding 11mg, 10mg, 9mg, 8mg, 7mg, 6mg, 5mg and 4mg amygdalin, performing ultrasonic treatment to dissolve the medicine, sucking 50 mu L of medicine, diluting with deionized water by a certain multiple, and determining the particle size. Taking amygdalin with different drug-loading rates from about 0.8mL to a centrifuge tube, and centrifuging for 15min at 4000 rpm. The particle size and whether the medicine is separated out after centrifugation are taken as standards, and the maximum medicine-loading rate of the particle size within the range of 10-200 nm is found, so that the optimal medicine-loading rate is determined.

The particle size change of the self-microemulsion preparation with different drug loading rates is shown in fig. 11, and the centrifugal stability of the drug is shown in table 5. As can be seen from FIG. 11, the particle size tends to increase with increasing drug loading, but the change is not so large in the range of 100 to 200 nm. As is clear from Table 5, when the drug loading was 4, 5 or 6mg/mL, no delamination occurred after centrifugation, and when the drug loading was 7, 8, 9, 10 or 11mg/mL, delamination occurred after centrifugation. And finally determining the drug loading rate to be 6mg/mL by integrating the particle size and the precipitation condition of the drug after centrifugation.

TABLE 5 centrifugal stability of different drug loadings

Example 8 amygdalin self-microemulsion appearance

Diluting the prepared amygdalin self-microemulsion with deionized water, observing the appearance of the self-microemulsion after the self-microemulsion is completely self-emulsified, and taking a picture. As shown in FIG. 11, the amygdalin self-microemulsion was diluted with deionized water to give a clear and transparent solution with blue opalescence.

Example 9 particle size and distribution of amygdalin self-microemulsions

Precisely weighing 6mg amygdalin, adding into 1mL blank self-microemulsion, mixing well, sucking 50 μ L, diluting with deionized water by a certain multiple, and determining particle size with a particle sizer after self-emulsification is complete. The amygdalin self-microemulsion has average particle diameter of (113.3 + -0.8) nm and polydispersity of (0.171 + -0.007). The results show that the amygdalin self-microemulsion particle size meets the requirements, and the particle size distribution is narrow and uniform.

Example 10

1. Centrifugal acceleration test

Precisely weighing 6mg amygdalin, adding into 1mL blank self-microemulsion, ultrasonically dissolving for 30min, mixing uniformly, centrifuging for 15min at 4000rpm, and observing whether layering phenomenon exists.

No layering is carried out, which shows that the amygdalin has good centrifugal stability from microemulsion.

2. Investigation of stability of standing

Precisely weighing 6mg amygdalin, adding into 1mL blank self-microemulsion, ultrasonic dissolving for 30min, mixing, standing at room temperature for 10 days, observing whether there is drug precipitation, and determining particle size.

In 10 days, no drug is precipitated from the microemulsion, and the particle size (118.4 +/-1.1) nm is measured on the 10 th day. The result shows that the amygdalin self-microemulsion has no obvious change in appearance and particle size within 10 days at room temperature, which indicates that the amygdalin self-microemulsion has good stability at room temperature.

3. Examination of dilution stability

Precisely weighing 6mg amygdalin, adding into 1mL blank self-microemulsion, ultrasonically dissolving for 30min, mixing well, sucking 50 μ L, adding deionized water to dilute 100 times, standing at room temperature for 10 days after self-emulsification is complete, and observing whether the appearance of the solution changes or not.

Within 10 days, the solution was clear and transparent with blue opalescence and no apparent change in appearance. The result shows that the amygdalin has better dilution stability from microemulsion at room temperature.

Claims

1. A self-microemulsion of amygdalin is characterized in that the self-microemulsion comprises amygdalin, an oil phase, an emulsifier and an auxiliary emulsifier;

the weight ratio of the oil phase in the self-microemulsion to the emulsifier to the co-emulsifier is (20-75) to (25-60) to (0.1-30);

the content of amygdalin in the self-microemulsion is less than or equal to 6 mg/mL;

the oily phase is selected from a mixture of ethyl oleate and Medium Chain Triglycerides (MCT); or the oily phase is selected from the group consisting of a mixture of glycerol monooleate and Medium Chain Triglycerides (MCT);

the emulsifier is selected from one or more of emulsifier OP, caprylic capric acid polyethylene glycol glyceride (Labrasol) and lauric acid polyethylene glycol-32 glyceride (glucire);

the auxiliary emulsifier is selected from one or more of 1, 2-propylene glycol and polyethylene glycol 400.

2. The self-microemulsion according to claim 1, wherein the weight ratio of the oil phase, the emulsifier and the co-emulsifier in the self-microemulsion is (35-50) to (30-50) to (5-20).

3. The self-microemulsion of claim 1, wherein the weight ratio of the oil phase, the emulsifier and the co-emulsifier in the self-microemulsion is (40-45) to (10-15).

4. The self-microemulsion of claim 1 wherein the weight ratio of the oil phase, emulsifier and co-emulsifier in the self-microemulsion is 45: 41.25: 13.75.

5. The self-microemulsion according to claim 1, wherein the content of amygdalin in the self-microemulsion is (4-6) mg/mL.

6. The self-microemulsion according to claim 1, wherein the content of amygdalin in the self-microemulsion is 6 mg/mL.

7. The self-microemulsion according to claim 1, wherein the amount ratio of ethyl oleate to medium-chain triglycerides (MCT) in the oil phase is (1-10): (1-10); or the dosage ratio of the glyceryl monooleate to the medium-chain triglyceride (MCT) in the oil phase is (1-10) to (1-10).

8. The self-microemulsion according to claim 7 wherein the amount ratio of ethyl oleate to Medium Chain Triglycerides (MCT) in the oil phase is 1: 1; or the dosage ratio of the glyceryl monooleate to the Medium Chain Triglyceride (MCT) in the oil phase mixture is 1: 1.

9. The self-microemulsion according to claim 1, wherein the particle size of the self-microemulsion is 50 to 500 nm.

10. The self-microemulsion according to claim 9, wherein the particle size of the self-microemulsion is 80 to 200 nm.

11. The self-microemulsion according to claim 9, wherein the particle size of the self-microemulsion is 100 to 150 nm.

12. The self-microemulsion according to claim 9, wherein the particle size of the self-microemulsion is (113.3 ± 0.8) nm.

13. A dosage form of amygdalin formulated as a self-microemulsion according to any one of claims 1-12.

14. The formulation of amygdalin prepared from microemulsion as claimed in claim 13, wherein the formulation is selected from oral, injectable, inhalant or transdermal.

15. The formulation of amygdalin self-microemulsion as claimed in claim 13, wherein said formulation is selected from the group consisting of tablets, capsules, granules, solid dispersions, injections, liposomes, microspheres, sprays, inhalants, emulsions and patches.

16. The formulation of amygdalin in self-microemulsion form as claimed in claim 13, wherein said formulation includes a self-microemulsion of amygdalin as defined above, and one or more pharmaceutically acceptable excipients.

17. The self-microemulsion of amygdalin as claimed in claim 16, wherein said pharmaceutically acceptable excipients are selected from one or more of the group consisting of fillers, binders, humectants, disintegrants, surfactants, adsorptive carriers, lubricants, injection solvents, buffers, bacteriostats, local anesthetics, isotonicity adjusting agents, suspending agents, protectants, bases, pigments, flavoring agents, sweeteners, solubilizing agents and absorption enhancers.

18. A process for the preparation of a self-microemulsion of amygdalin as claimed in any one of claims 1-12, wherein said process comprises the steps of: adding amygdalin into oil phase, emulsifier and auxiliary emulsifier, and performing ultrasonic treatment, shaking and filtering.

19. A method of preparing a self-microemulsion of amygdalin as claimed in claim 18, comprising the steps of: weighing the oil phase, the emulsifier and the co-emulsifier according to the formula amount, adding the amygdalin according to the formula amount, carrying out ultrasonic treatment for 20-50 min, placing in a constant-temperature water bath oscillator at 20-40 ℃ for oscillation for 12-36 h, filtering supernate with a microporous filter membrane, and discarding primary filtrate.

20. A method of preparing a self-microemulsion of amygdalin as claimed in claim 18, comprising the steps of: weighing the oil phase, the emulsifier and the coemulsifier according to the prescription amount, adding the amygdalin according to the prescription amount, carrying out ultrasonic treatment for 30min, placing in a constant-temperature water bath oscillator at 37 ℃ for shaking for 24h, filtering supernate with a 0.22 mu m microporous filter membrane, and discarding the primary filtrate.