CN110917125B

CN110917125B - Preparation method of rotigotine nasal micelle temperature-sensitive gel

Info

Publication number: CN110917125B
Application number: CN202010000952.9A
Authority: CN
Inventors: 桂双英; 杨转转; 王方园; 舒子璇; 刘梦丽
Original assignee: Anhui University of Traditional Chinese Medicine AHUTCM
Current assignee: Anhui University of Traditional Chinese Medicine AHUTCM
Priority date: 2020-01-02
Filing date: 2020-01-02
Publication date: 2022-08-12
Anticipated expiration: 2040-01-02
Also published as: CN110917125A

Abstract

The invention relates to the technical field of pharmaceutical preparations, in particular to a preparation method of rotigotine nasal micelle temperature-sensitive gel. Dissolving rotigotine and a polymer carrier material in an organic solvent to form an organic phase, slowly dripping the organic phase into pure water, and stirring to obtain a rotigotine polymer micelle; and then adding a temperature-sensitive gel matrix into the rotigotine polymer micelle, uniformly mixing, and exhausting bubbles to obtain the rotigotine nasal micelle temperature-sensitive gel. The invention overcomes the defects of extremely low oral bioavailability and strong fat solubility of the rotigotine, combines the advantages of the polymer micelle and the temperature-sensitive gel, and develops the nasal rotigotine polymer micelle temperature-sensitive gel composite system. The polymer micelle effectively improves the solubility of the rotigotine in water, and the prepared rotigotine micelle temperature-sensitive gel is in a solution state at a lower temperature and can be quickly converted into gel at a nasal cavity temperature, so that the preparation is favorably adhered to the nasal cavity, the bioavailability of the medicine is high, and the brain targeting is good.

Description

Preparation method of rotigotine nasal micelle temperature-sensitive gel

Technical Field

The invention relates to the technical field of pharmaceutical preparations, in particular to a preparation method of rotigotine nasal micelle temperature-sensitive gel.

Background

Rotigotine is a novel non-ergot selective dopamine receptor agonist that acts against parkinson by stimulating dopamine receptors in the body and mimicking the neurotransmitter dopamine. However, the first-pass effect of rotigotine is very obvious, the bioavailability is extremely low (< 1% -5%), and the rotigotine is not suitable for oral administration. Currently, only rotigotine transdermal patches are marketed as formulations

The patch has good therapeutic effect and can reduce motor complications. However, clinical application shows that most of the drugs can generate local side effects such as erythema, pruritus and the like, and the compliance of patients is reduced. In 2008, the patch appeared to crystallize, and the amount of drug available for release was reduced to change the therapeutic effect. And then cold chain storage and distribution are adopted (2-8 ℃), and each prescription does not exceed 1 month, so that crystallization can be avoided, but the difficulty is obviously increased for patients to use.

In recent years, nasal administration has received much attention as a convenient and reliable administration method. The nasal administration can avoid the degradation of the medicine in the gastrointestinal tract and the first pass effect of the liver, improve the bioavailability and is suitable for the medicine which is not suitable for oral administration and the patients who cannot take the medicine orally. In addition, the nasal route can bypass the blood brain barrier, deliver drugs directly to the brain via the olfactory or trigeminal routes, provide more opportunities for the drug to enter the central nervous system, and is a non-invasive and effective way of administering brain diseases.

The in-situ gel is a novel drug delivery system, and utilizes the stimulation (such as pH, temperature or ionic strength and the like) of a high molecular material to the outside to react, so that the polymer can be reversibly transformed at the administration part and is changed from a solution state to a semisolid gel state, thereby overcoming the clearance of nasal cilia. The preparation method is simple, has strong affinity with a plurality of application parts such as mucosal tissues and the like, prolongs the retention time of the medicament, has a certain sustained and controlled release effect, and is a research hotspot in the field of pharmacy. Based on the above, the rotigotine nasal micelle temperature-sensitive gel is developed, and no report related to the rotigotine micelle temperature-sensitive gel is found at present.

Disclosure of Invention

Aiming at the technical problems in the prior art, the invention aims to provide a preparation method of rotigotine nasal micelle temperature-sensitive gel, which can effectively improve the solubility of fat-soluble drugs and remarkably increase the absorption of the drugs.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows: a preparation method of rotigotine nasal micelle temperature-sensitive gel comprises the steps of dissolving rotigotine and a polymer carrier material in an organic solvent to form an organic phase, slowly dripping the organic phase into pure water, and stirring to obtain rotigotine polymer micelles; and then adding a temperature-sensitive gel matrix into the rotigotine polymer micelle, uniformly mixing, and exhausting bubbles to obtain the rotigotine nasal micelle temperature-sensitive gel.

As a preferred technical scheme of the preparation method, the preparation method comprises the following specific steps:

(1) dissolving rotigotine and a polymer carrier material in an organic solvent, dropwise adding the solution into pure water which is stirred at a constant speed, slowly stirring at room temperature, and volatilizing the residual solvent to obtain rotigotine polymer micelles;

(2) adding poloxamer 188 and poloxamer 407 into the rotigotine polymer micelle, uniformly mixing, refrigerating and exhausting bubbles to obtain the rotigotine nasal micelle temperature-sensitive gel.

Preferably, in the step (1), rotigotine accounts for 20-30% of the weight of the polymer carrier material, and the initial concentration of the polymer carrier material in the organic solvent is 20-50 mg/mL.

Preferably, the volume ratio of the organic solvent to the pure water in the step (1) is 1: 2-8, wherein the organic solvent is one of acetone, dichloromethane, methanol and absolute ethyl alcohol, and acetone is more preferable.

Preferably, the polymer carrier material in step (1) is mPEG-PLA (monomethoxypolyethylene glycol-polylactic acid block copolymer), mPEG-PDLLA (monomethoxypolyethylene glycol-poly DL-lactic acid block copolymer), mPEG-PLGA (monomethoxypolyethylene glycol-poly lactic acid-glycolic acid block copolymer), PEG-PASp (polyethylene glycol-poly L-aspartic acid derivative block copolymer) or the like.

Preferably, in the step (2), the mass percentages of the poloxamer 407 and the poloxamer 188 in the rotigotine polymer micelle are 20-24% and 0-4%, respectively.

Preferably, the particle size of the rotigotine polymer micelle prepared in the step (1) is 30-100 nm.

Further, the method also comprises a process of adding a pH regulator and a preservative after the rotigotine nasal micelle temperature-sensitive gel is prepared in the step (2). Specifically, 30% (w/v) of tris (hydroxymethyl) aminomethane is added into the rotigotine nasal micelle temperature-sensitive gel to adjust the pH value to 4.5-6.5. Tris can also be replaced with conventional buffer salts. Then 0.02% (w/v) (i.e. 0.02g benzalkonium bromide per 100mL of temperature sensitive gel) of benzalkonium bromide was added to the rotigotine nasal micelle temperature sensitive gel as preservative. Benzalkonium bromide may be replaced by benzalkonium chloride, parabens, sorbic acid, benzoic acid and its salts, chlorhexidine acetate, etc.

Because rotigotine has strong lipid solubility, rotigotine is difficult to effectively disperse in the water-soluble temperature-sensitive in-situ gel. The polymer micelle adopted by the invention is a self-assembly body which is formed by self-assembling amphiphilic copolymer in an aqueous medium and has a hydrophilic shell and a hydrophobic core, can effectively improve the solubility of fat-soluble medicines and remarkably increase the absorption of the medicines, and has small particle size, large drug-loading rate, high stability and passive targeting property. Compared with the prior art, the invention has the beneficial effects that:

(1) the invention overcomes the defects that the rotigotine has strong lipid solubility and poor water solubility and is difficult to effectively disperse in the preparation, and the polymer micelle improves the solubility of the rotigotine in water.

(2) The rotigotine micelle temperature-sensitive gel provided by the invention is in a solution state at a lower temperature, can be quickly converted into a gel at a nasal cavity temperature, is beneficial to the adhesion of a preparation in the nasal cavity, has high bioavailability and improves the drug concentration in brain tissues.

(3) The preparation of the invention has convenient use, good dispersibility, high bioavailability and good brain targeting property.

(4) The method has the advantages of simple operation, easily obtained raw materials, low cost, small irritation and great application prospect.

Drawings

FIG. 1 is a graph of modulus versus temperature for rheological characteristics; g '(viscous modulus), G' (elastic modulus).

Fig. 2 is a graph of drug distribution in brain tissue of rats at different time points after administration (n-4, mean ± SD).

FIG. 3 is an optical microscope observation of the morphology of cilia of the upper palate of a toad 30min after administration (x 400); wherein, A-physiological saline; b-1% sodium deoxycholate; c-blank gel group; d-drug-loaded gel group.

Detailed Description

The present invention will be described in further detail with reference to examples, but the present invention is not limited thereto.

Example 1

A preparation method of rotigotine micelle temperature-sensitive gel comprises the following steps:

(1) weighing 6mg of rotigotine and 30mg of mPEG-PLA, adding 1mL of acetone to dissolve the rotigotine and the mPEG-PLA, dropwise adding the solution into 5mL of rapidly-stirred pure water, and continuously stirring for 4 hours until the residual solvent is volatilized to obtain the rotigotine polymer micelle. The particle size of the polymer micelle was found to be (95.84. + -. 8.75) nm, and the encapsulation efficiency was found to be (89.08. + -. 0.09)%.

(2) Adding 21.84 percent of poloxamer 407 and 2.17 percent of poloxamer 188 into the rotigotine polymer micelle, uniformly mixing, storing at 4 ℃ for 24h, fully swelling and exhausting bubbles to prepare rotigotine nasal micelle temperature-sensitive gel, adding 0.001g of benzalkonium bromide, adding 6 mu L of 30 percent of tris (hydroxymethyl) aminomethane to adjust the pH value to 4.760, and measuring the gelation temperature of the embodiment to be 33.0 ℃ by a test tube inversion method.

Example 2

(1) weighing 15mg of rotigotine and 50mg of mPEG-PLGA, adding 2mL of dichloromethane to dissolve, dropwise adding the solution into 10mL of rapidly-stirred pure water, and continuously stirring for 4 hours until the residual solvent is volatilized to obtain the rotigotine polymer micelle. The particle size of the polymer micelle was found to be (88.62. + -. 1.47) nm, and the encapsulation efficiency was found to be (93.5. + -. 0.79)%.

(2) Adding 22.69 wt% of poloxamer 407 and 2.58 wt% of poloxamer 188 into the rotigotine polymer micelle, mixing, storing at 4 ℃ for 24h, fully swelling and exhausting bubbles to obtain rotigotine nasal micelle temperature-sensitive gel, adding 0.001g of benzalkonium bromide, adding 6 mu L of 30% tris (hydroxymethyl) aminomethane, and adjusting the pH value to 5.186.

The rotigotine micelle temperature-sensitive gel obtained in the example can complete the rapid sol-gel conversion at about 31.3 ℃, and the change curves of the viscous modulus and the elastic modulus along with the temperature in the rheological experiment are shown in figure 1.

Taking 60 healthy SD rats with half of male and female, randomly dividing into a rotigotine micelle temperature-sensitive gel nasal administration group and a rotigotine solution intravenous administration group, wherein each group comprises 4 rotigotine micelles with administration dosage of 0.75mg/kg, after anesthesia of chloral hydrate, each rat is subjected to single-side nostril administration by using a microinjector connected with a PE-10 tube, and the intravenous injection group is subjected to administration according to the volume of 0.1mL/100 g. Blood is taken from angular veins of eyes at 0.5, 1, 2, 4 and 8h after administration, the rat is killed by means of vertebral dislocation after the last blood taking, the rat olfactory bulb, cerebral cortex, cerebellum and striatum tissues are respectively taken, washed by normal saline, blotted by filter paper, weighed, placed in a freezing storage tube and stored in a refrigerator at minus 80 ℃ for standby.

Fig. 2 shows that rotigotine micelle temperature-sensitive gel is administered to a rat through nasal cavity administration (a) and a rat tail vein injection administration (b) by rotigotine solution at a dose of 0.75mg/kg, drug distribution conditions in brain tissues after administration at different time points are shown in fig. 2, the drugs are distributed in all brain regions, and AUCs of the drugs in olfactory bulbs, cerebral cortex, cerebellum and striatum are all remarkably larger than those in an intravenous injection group (P is less than 0.05), which indicates that the micelle temperature-sensitive gel can remarkably improve the concentration of rotigotine in the brain tissues, and is beneficial to better exerting curative effect of the drugs at lesion sites.

Brain targeting evaluation: bioavailability, DTI and DTP results of nasal administration of rotigotine micelle temperature sensitive gel are shown in Table 1.

TABLE 1 bioavailability and brain targeting parameters of rotigotine micelle temperature sensitive gels

Parameter(s)	Blood plasma	Smell ball	Cerebral cortex	Cerebellum	Striatum body
						Bioavailability F (%)	84.6	276.6	170.5	166.5	184.4
Brain targeting index DTI	--	3.27	2.01	1.97	2.18
						Percentage nasal brain transport DTP (%)	--	69.39	50.35	49.15	54.09

The absolute bioavailability of the rotigotine micelle temperature-sensitive gel is 84.6%. The bioavailability of the drug in olfactory bulb, cerebral cortex, cerebellum and striatal tissue was 276.6%, 170.5%, 166.5% and 184.4%, respectively. DTI in each brain tissue after the micelle temperature-sensitive gel nasal administration is more than 1, and the micelle temperature-sensitive gel nasal administration has targeting property, wherein the olfactory bulb has the best targeting property; the DTP of the micelle temperature-sensitive gel in olfactory bulb, cerebral cortex, cerebellum and striatum tissues is 69.39%, 50.35%, 49.15% and 54.09% respectively, and further proves that rotigotine can be directly transported to the brain through an olfactory pathway after nasal administration.

Example 3

(1) weighing 10mg of rotigotine and 50mg of mPEG-PDLLA, adding 1mL of absolute ethanol to dissolve, dropwise adding the solution into 5mL of rapidly-stirred pure water, and continuously stirring for 4h until residual solvent is volatilized to obtain the rotigotine polymer micelle. The particle size of the polymer micelle was found to be (83.26. + -. 1.21) nm, and the encapsulation efficiency was found to be (94.36. + -. 0.52)%.

(2) Adding 23.06% of poloxamer 407 and 3.27% of poloxamer 188 into the rotigotine polymer micelle, mixing uniformly, storing at 4 ℃ for 24h, fully swelling and exhausting bubbles to obtain rotigotine nasal micelle temperature-sensitive gel, adding 0.001g of benzalkonium bromide, adding 6 mu L of 30% of tris (hydroxymethyl) aminomethane to adjust the pH value to 5.417, and measuring the gelation temperature of the embodiment to be 31.3 ℃ by using a test tube inversion method.

Dividing 12 large toads into 4 groups, respectively administering normal saline, 1% sodium deoxycholate, drug-loaded micelle temperature-sensitive gel and blank micelle temperature-sensitive gel to the palatine mucosa, and after administration for 30min, observing the results of an optical microscope for the morphology of the cilia of the palatine toads, wherein the results are shown in figure 3, and the rotigotine micelle temperature-sensitive gel does not have obvious toxic or side effect on cilia primarily.

In conclusion, the invention overcomes the defects of extremely low oral bioavailability and strong fat solubility of rotigotine, and combines the advantages of the polymer micelle and the temperature-sensitive gel, so that the polymer micelle effectively improves the solubility of rotigotine in water. The polymer micelle effectively improves the solubility of the rotigotine in water, and the prepared rotigotine micelle temperature-sensitive gel is in a solution state at a lower temperature and can be quickly converted into gel at a nasal cavity temperature, so that the preparation is favorably adhered to the nasal cavity, the bioavailability of the medicine is high, and the brain targeting is good. Meanwhile, experiments show that the medicine and the auxiliary materials thereof have no obvious toxic or side effect on toad palate cilium and rat nasal mucosa, and the safety is good, so that the feasibility of intranasal administration of the rotigotine micelle temperature-sensitive gel composite medicine carrying system is verified.

The rotigotine has very strong lipid solubility and is insoluble in water, and the solubility in pure water is only 0.017mg/mL, after the rotigotine is prepared into the polymer gel, the mass concentration of the drug can reach (2.98 +/-0.92) mg/mL, so that the solubility of the drug is obviously improved, the rotigotine is dispersed in the water-soluble temperature-sensitive gel at a larger mass concentration, and the requirement of nasal administration of the rotigotine temperature-sensitive gel is met.

When the concentration of poloxamer 407(P407) in the mixture ratio is increased, the gelling temperature is reduced; while poloxamer 188(P188) concentration increases, the gelling temperature increases. P407 and P188 are amphiphilic synthetic copolymers consisting of 2 hydrophilic polyethylene oxide (PEO) blocks and hydrophobic polypropylene oxide (PPO) blocks. The P407 is approximately composed of 70% PEO and 30% PPO, the gelation mechanism of the P407 solution is controlled by the dehydration of hydrophobic PPO blocks, when the temperature is increased, the hydrophobic PPO is dehydrated, the hydrophobic interaction between PPO is caused, spherical micelles with hydrophobic PPO cores and hydrophilic PEO shells are formed, and the micelles are entangled with other micelles at the critical temperature to form a three-dimensional network structure. As the concentration of P407 increases, the gel structure becomes more tightly aligned with the entanglement of the micelles, and gelation occurs rapidly at a lower temperature. Whereas the addition of P188 (containing about 84% PEO and 16% PPO) will reduce the PPO to PEO ratio, resulting in more extensive intermolecular hydrogen bonding, thereby increasing the gelation temperature.

Experiments prove that the micelle temperature-sensitive gel can slowly release the drug, and the condition that the drug is suddenly released does not occur, probably because the encapsulation rate of the rotigotine in the polymer micelle is high (about 93.5%), the drug is highly encapsulated in the hydrophobic core of the micelle, and the drug is released when the polymer micelle is broken or degraded. For a composite system of the polymer micelle and the temperature-sensitive gel, the polymer micelle or the drug needs to be further released through the diffusion of a gel matrix, so that the slow release of the drug can be realized.

The foregoing is illustrative and explanatory only of the inventive concept, and it is intended that those skilled in the art, upon attaining an understanding of the present invention, will readily produce alterations to, variations of, and equivalents to such embodiments without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A preparation method of rotigotine nasal micelle temperature-sensitive gel is characterized in that rotigotine and a polymer carrier material are dissolved in an organic solvent to form an organic phase, the organic phase is slowly dripped into pure water, and the rotigotine polymer micelle is obtained by stirring; and then adding a temperature-sensitive gel matrix into the rotigotine polymer micelle, uniformly mixing and exhausting bubbles to prepare the rotigotine nasal micelle temperature-sensitive gel, wherein the specific steps are as follows:

the rotigotine accounts for 20-30% of the weight of the polymer carrier material, and the initial concentration of the polymer carrier material in the organic solvent is 20-50 mg/mL; the polymer carrier material is mPEG-PLA, mPEG-PDLLA or mPEG-PLGA;

(2) adding poloxamer 188 and poloxamer 407 into the rotigotine polymer micelle, uniformly mixing, and refrigerating to discharge bubbles; poloxamer 407 and poloxamer 188 account for 20-24% and 2.17-4% of the rotigotine polymer micelle by weight percent respectively;

(3) adding trihydroxymethyl aminomethane into the rotigotine nasal micelle temperature-sensitive gel to adjust the pH value to be 4.5-6.5, and adding benzalkonium bromide as a preservative to prepare the rotigotine nasal micelle temperature-sensitive gel.

2. The production method according to claim 1, wherein the volume ratio of the organic solvent to the pure water in step (1) is 1: 2 to 8.

3. The preparation method according to claim 1, wherein the particle size of the rotigotine polymer micelle prepared in step (1) is 30-100 nm.

4. The rotigotine nasal micelle temperature-sensitive gel prepared by the preparation method according to any one of claims 1 to 3.