Disclosure of Invention
In order to overcome the defects and shortcomings in the prior art, the invention mainly aims to provide a preparation method of a triptolide ophthalmic material.
The preparation method comprises the steps of carrying out structural modification on triptolide by a chemical means, carrying out esterification reaction on hydroxyl of the triptolide and carboxyl of p-aldehyde benzoic acid with small molecular weight to generate triptolide p-aldehyde benzyl ester, forming a dynamic bond Schiff base bond by utilizing the action of the aldehyde group of the triptolide p-aldehyde benzyl ester and amino of carboxymethyl chitosan with good biocompatibility, and chelating copper ions released by nano-copper and the carboxyl of the carboxymethyl chitosan to form gel, thereby obtaining the triptolide ophthalmic material. The triptolide ophthalmic material has good biological safety, low toxicity, long-acting slow release and high bioavailability.
The other purpose of the invention is to provide the triptolide ophthalmic material prepared by the preparation method.
The invention also aims to provide application of the triptolide ophthalmic material.
A preparation method of triptolide ophthalmic material comprises the following steps:
(1) dissolving triptolide in a solvent, adding p-aldehyde benzoic acid and 4-Dimethylaminopyridine (DMAP) under the protection of nitrogen, reacting at room temperature, and purifying to obtain triptolide p-aldehyde benzyl ester;
(2) uniformly mixing carboxymethyl chitosan and triptolide p-aldehyde benzyl ester, adding water, stirring to uniformly disperse and completely dissolve the mixture to obtain carboxymethyl chitosan-triptolide p-aldehyde benzyl ester solution; putting the nano copper powder in water, performing ultrasonic treatment, and uniformly dispersing to form a nano copper suspension;
(3) adding the nano-copper suspension into carboxymethyl chitosan-triptolide p-formaldehyde benzyl ester solution under stirring, standing to form gel, and solidifying to obtain triptolide ophthalmic material.
Preferably, the solvent in step (1) is at least one of pyridine, dimethyl sulfoxide, tetrahydrofuran and dimethylformamide.
Preferably, the room temperature in the step (1) is 25 ℃, and the reaction time is 24-36 h.
Preferably, the molar ratio of triptolide to p-aldehyde benzoic acid in the step (1) is 1: (1-2), namely the mass ratio of the triptolide to the p-aldehyde benzoic acid is 108: (45-90).
Preferably, the mass ratio of the triptolide to the 4-dimethylaminopyridine in the step (1) is (18-24): 1.
preferably, the ratio of the triptolide and the solvent in the step (1) is 10.8-21.6 mg/ml.
Preferably, the purification method in step (1) is: and (2) performing thin-layer chromatography (petroleum ether: ethyl acetate: 1: 5-10) on the mixed product, then adding excessive ethyl acetate for dilution, then washing with saturated copper sulfate solution and sodium chloride aqueous solution in sequence, separating and purifying to obtain an organic layer, then drying with anhydrous sodium sulfate, filtering to obtain a filtrate, concentrating, and finally purifying by silica gel column chromatography (dichloromethane/methanol, 10-15: 1) to obtain pure triptolide p-formyl benzyl ester.
Preferably, the mass ratio of the carboxymethyl chitosan to the triptolide p-aldehyde benzyl ester in the step (2) is 20-80: 1.
preferably, in the carboxymethyl chitosan-triptolide p-formaldehyde benzyl ester solution in the step (2), the concentration of the carboxymethyl chitosan is 2-4 wt%, and the concentration of the triptolide p-formaldehyde benzyl ester is 0.5-1 mg/ml.
Preferably, the rotation speed of the water adding and stirring in the step (2) is 800-1200 rpm, and the time is 3-6 h; the ultrasonic time is 15-30 min.
Preferably, in the nano-copper suspension in the step (2), the ratio of the nano-copper to the water is 1.5-3 mg/ml.
Preferably, the volume ratio of the nano-copper suspension in the step (3) to the carboxymethyl chitosan-triptolide-p-formaldehyde benzyl ester solution is 1: (4.5-9).
Preferably, the adding in the step (3) refers to dropwise adding the nano-copper suspension into the carboxymethyl chitosan-triptolide p-formaldehyde benzyl ester solution within 10-20 min.
Preferably, the stirring speed in the step (3) is 500-1000 rpm, and the time is 5-10 h; the standing time is 24-36 h.
Preferably, the nano-copper suspension and the carboxymethyl chitosan-triptolide p-formaldehyde benzyl ester solution in the step (3) are stirred and kept stand to form a gel state, then the gel state is filled into a syringe with a needle for extrusion injection, and after solidification, the gel state is cut into a small rod shape, wherein the diameter of the small rod shape is 0.01-0.1 cm, and the length of the small rod shape is 0.2-0.5 cm.
The triptolide ophthalmic material prepared by the method.
The application of the triptolide ophthalmic material is provided.
Preferably, the triptolide ophthalmic material is applied to pharmaceutical preparations.
The carboxymethyl chitosan is a biological high molecular polymer, has no stimulation, good biocompatibility, biological adhesion and biodegradability, has no toxicity of degradation products, can be completely absorbed by organisms, and is widely concerned as an ideal drug carrier. The research shows that a small amount of copper ions have no stimulation and toxic or side effect on eyes. The invention generates triptolide p-aldehyde benzyl ester by using the esterification reaction of triptolide hydroxyl and carboxyl of p-aldehyde benzoic acid with small molecular weight, and then forms a dynamic Schiff base bond by using the action of the aldehyde group of the triptolide p-aldehyde benzyl ester and the self-carried amino group of carboxymethyl chitosan with good biocompatibility, so that the triptolide p-aldehyde benzyl ester can easily fall off during treatment, and the curative effect can be exerted. And then the copper ions released by the nano-copper are chelated with the carboxyl of the carboxymethyl chitosan to form gel, so as to obtain the triptolide ophthalmic material. The toxicity of the medicine is weakened, the defect of poor solubility is improved, the bioavailability of the medicine is improved, and the half-life period of the medicine is prolonged, so that the long-acting treatment effect is achieved.
Compared with the prior art, the invention has the following advantages and beneficial effects:
(1) the triptolide ophthalmic material prepared by the invention has good biological safety, and the triptolide drug micromolecules are easy to fall off from the carrier so as to exert the drug effect, and the bioavailability is high.
(2) The triptolide ophthalmic material prepared by the invention has the advantages of abundant and easily obtained raw materials, simple production process of the product and easy preparation.
(3) The triptolide ophthalmic material prepared by the invention can be used as a novel pharmaceutical preparation to be applied to clinically preventing corneal transplantation rejection, reducing the administration frequency, having good curative effect and wide application value.
Detailed Description
The present invention will be described in further detail with reference to examples and drawings, but the embodiments of the present invention are not limited thereto.
Those who do not specify specific conditions in the examples of the present invention follow conventional conditions or conditions recommended by the manufacturer. The raw materials, reagents and the like which are not indicated for manufacturers are all conventional products which can be obtained by commercial purchase.
Example 1
(1) Dissolving 108mg triptolide in 5ml pyridine, adding 45mg p-aldehyde benzoic acid and 6mg 4-Dimethylaminopyridine (DMAP) under the protection of nitrogen, reacting for 24h at room temperature and 25 ℃, taking a mixed product, carrying out thin-layer chromatography (petroleum ether: ethyl acetate: 1: 5), then adding excessive ethyl acetate for dilution, still washing with a saturated copper sulfate solution and a sodium chloride aqueous solution, separating and purifying to obtain an organic layer, then drying with anhydrous sodium sulfate, filtering to obtain a filtrate, concentrating, and finally purifying by silica gel column chromatography (dichloromethane/methanol, 10: 1) to obtain triptolide p-aldehyde benzyl ester;
(2) uniformly mixing 0.4g of carboxymethyl chitosan powder with 10mg of triptolide p-formaldehyde benzyl ester, adding 18ml of water, stirring at the rotating speed of 800rpm for 3 hours to uniformly disperse and completely dissolve the mixture to obtain carboxymethyl chitosan-triptolide p-formaldehyde benzyl ester solution; putting 4mg of nano copper powder in 2ml of water, performing ultrasonic treatment for 15min, and uniformly dispersing to form a suspension;
(3) and (3) adding 2ml of the nano-copper suspension prepared in the step (2) into 18ml of carboxymethyl chitosan-triptolide p-formaldehyde benzyl ester solution within 10min under the stirring state at the rotating speed of 500rpm, stirring for 5h, standing for 24h to form a gel state, putting into a syringe with a needle head, extruding and injecting, and cutting into a small rod shape with the diameter of 0.1mm and the length of 2mm after solidification to obtain the triptolide ophthalmic material.
Example 2
(1) Dissolving 108mg triptolide in 5ml dimethyl sulfoxide, adding 90mg p-aldehyde benzoic acid and 4.5mg 4-Dimethylaminopyridine (DMAP) under the protection of nitrogen, reacting at room temperature of 25 ℃ for 36h, taking a mixed product, carrying out thin-layer chromatography (petroleum ether: ethyl acetate: 1: 10), then adding excessive ethyl acetate for dilution, still washing with a saturated copper sulfate solution and a sodium chloride aqueous solution, separating and purifying to obtain an organic layer, then drying with anhydrous sodium sulfate, filtering to obtain a filtrate, concentrating, and finally purifying by silica gel column chromatography (dichloromethane/methanol, 15: 1) to obtain triptolide p-aldehyde benzyl ester;
(2) uniformly mixing 0.8g of carboxymethyl chitosan powder with 20mg of triptolide p-formaldehyde benzyl ester, adding 18ml of water, stirring at the rotating speed of 1200rpm for 6 hours to uniformly disperse and completely dissolve the mixture to obtain carboxymethyl chitosan-triptolide p-formaldehyde benzyl ester solution; putting 6mg of nano copper powder in 4ml of water, performing ultrasonic treatment for 30min, and uniformly dispersing to form a suspension;
(3) and (3) adding 4ml of the nano-copper suspension prepared in the step (2) into 18ml of carboxymethyl chitosan-triptolide p-formaldehyde benzyl ester solution within 20min under the stirring state at the rotating speed of 1000rpm, stirring for 10h, standing for 36h to form a gel state, putting into a syringe with a needle head, extruding and injecting, and cutting into a small rod with the diameter of 1mm and the length of 5mm after solidification to obtain the triptolide ophthalmic material.
Example 3
(1) Dissolving 108mg triptolide in 5ml tetrahydrofuran, adding 68mg p-aldehyde benzoic acid and 5mg 4-Dimethylaminopyridine (DMAP) under the protection of nitrogen, reacting at room temperature of 25 ℃ for 30h, taking a mixed product, carrying out thin-layer chromatography (petroleum ether: ethyl acetate: 1: 7), then adding excessive ethyl acetate for dilution, still washing with a saturated copper sulfate solution and a sodium chloride aqueous solution, separating and purifying to obtain an organic layer, then drying with anhydrous sodium sulfate, filtering to obtain a filtrate, concentrating, and finally purifying by silica gel column chromatography (dichloromethane/methanol, 12: 1) to obtain triptolide p-aldehyde benzyl ester;
(2) uniformly mixing 0.6g of carboxymethyl chitosan powder with 15mg of triptolide p-aldehyde benzyl ester, adding 18ml of water, stirring at the rotating speed of 1000rpm for 4.5 hours to uniformly disperse and completely dissolve the carboxymethyl chitosan-triptolide p-aldehyde benzyl ester solution to obtain a carboxymethyl chitosan-triptolide p-aldehyde benzyl ester solution; putting 5mg of nano copper powder in 3ml of water, performing ultrasonic treatment for 23min, and uniformly dispersing to form a suspension;
(3) and (3) adding the 3ml of nano-copper suspension prepared in the step (2) into 18ml of carboxymethyl chitosan-triptolide p-formaldehyde benzyl ester solution within 15min under the stirring state with the rotation speed of 750rpm, stirring for 7.5h, standing for 30h to form a gel state, filling into a syringe with a needle head, extruding and injecting to solidify, and shearing into a small rod with the diameter of 0.5mm and the length of 3.5mm to obtain the triptolide ophthalmic material.
Example 4
(1) Dissolving 108mg triptolide in 5ml dimethylformamide, adding 45mg p-aldehyde benzoic acid and 6mg 4-Dimethylaminopyridine (DMAP) under the protection of nitrogen, reacting at room temperature of 25 ℃ for 24h, taking a mixed product, carrying out thin-layer chromatography (petroleum ether: ethyl acetate is 1: 10), then adding excessive ethyl acetate for dilution, still washing with a saturated copper sulfate solution and a sodium chloride aqueous solution, separating and purifying to obtain an organic layer, then drying with anhydrous sodium sulfate, filtering to obtain a filtrate, concentrating, and finally purifying by silica gel column chromatography (dichloromethane/methanol, 10: 1) to obtain triptolide p-aldehyde benzyl ester;
(2) uniformly mixing 0.8g of carboxymethyl chitosan powder with 10mg of triptolide p-formaldehyde benzyl ester, adding 18ml of water, stirring at the rotating speed of 1200rpm for 3 hours to uniformly disperse and completely dissolve the carboxymethyl chitosan-triptolide p-formaldehyde benzyl ester solution to obtain a carboxymethyl chitosan-triptolide p-formaldehyde benzyl ester solution; putting 6mg of nano copper powder in 2ml of water, performing ultrasonic treatment for 15min, and uniformly dispersing to form a suspension;
(3) and (3) adding 2ml of the nano-copper suspension prepared in the step (2) into 18ml of carboxymethyl chitosan-triptolide p-formaldehyde benzyl ester solution within 10min under the stirring state at the rotating speed of 1000rpm, stirring for 10h, standing for 24h to form a gel state, putting into a syringe with a needle head, extruding and injecting, and cutting into a small rod with the diameter of 0.1mm and the length of 5mm after solidification to obtain the triptolide ophthalmic material.
Example 5
(1) Dissolving 108mg triptolide in 5ml pyridine, adding 90mg p-aldehyde benzoic acid and 4.5mg 4-Dimethylaminopyridine (DMAP) under the protection of nitrogen, reacting at room temperature of 25 ℃ for 36h, taking a mixed product, carrying out thin-layer chromatography (petroleum ether: ethyl acetate: 1: 5), then adding excessive ethyl acetate for dilution, still washing with a saturated copper sulfate solution and a sodium chloride aqueous solution, separating and purifying to obtain an organic layer, then drying with anhydrous sodium sulfate, filtering to obtain a filtrate, concentrating, and finally purifying by silica gel column chromatography (dichloromethane/methanol, 15: 1) to obtain triptolide p-aldehyde benzyl ester;
(2) uniformly mixing 0.4g of carboxymethyl chitosan powder with 20mg of triptolide p-formaldehyde benzyl ester, adding 18ml of water, stirring at the rotating speed of 1200rpm for 3 hours to uniformly disperse and completely dissolve the carboxymethyl chitosan-triptolide p-formaldehyde benzyl ester solution to obtain a carboxymethyl chitosan-triptolide p-formaldehyde benzyl ester solution; putting 6mg of nano copper powder in 4ml of water, performing ultrasonic treatment for 30min, and uniformly dispersing to form a suspension;
(3) and (3) under the stirring state with the rotation speed of 500rpm, adding 4ml of the nano-copper suspension prepared in the step (2) into 18ml of carboxymethyl chitosan-triptolide p-formaldehyde benzyl ester solution within 20min, stirring for 5h, standing for 36h to form a gel state, putting into a syringe with a needle head, extruding and injecting, after solidification, shearing into a small rod shape with the diameter of 1mm and the length of 2mm, and obtaining the triptolide ophthalmic material.
Example 6
Under the same condition as that of the other conditions of the embodiment 1, nano-copper suspension liquid (the concentration is respectively 2mg/ml, 0.1mg/ml and 6mg/ml) with different concentrations is added into carboxymethyl chitosan-triptolide p-formaldehyde benzyl ester solution, the solution is stirred and kept stand to form a gel state, the gel state is filled into the same syringe with a needle head to be extruded and injected, and after solidification, the three are extruded and injected, in order to compare the strength and the toughness of the three more intuitively, the three are not sheared, and when the eye is implanted, the three are sheared into a small bar shape, the size diameter of the small bar is 0.1mm-1mm, and the length of the small bar is 2-5 mm, so that different triptolide ophthalmic materials are obtained.
As shown in figure 2, the concentration of the nano-copper suspension added in the group a is 2mg/ml, the concentration of the group b and the concentration of the group c are respectively 0.1mg/ml and 6mg/ml, and compared with the three groups, the group a can still recover after being folded in half, and the group b and the group c can be broken and have poor toughness; and the surface of a is smoother, and the surfaces of b and c are similar to flocculent fibers, so that sticky tissues are easily caused. In fig. 1, the electron microscope image also shows that a has a smooth surface, so that the group a is more suitable for being implanted into the eye.
Example 7 drug Release test
The triptolide ophthalmic material prepared according to the method of example 1 was put into a dialysis bag (MWCO ═ 2000Da), and was shaken in a 0.01mol/L PBS solution (phosphate buffer solution) having a pH of 7.4 at 37 ℃ in a shaker, 2mL of the above PBS solution containing the drug was periodically taken out, and 2mL of fresh PBS solution was immediately added, and the light absorption value of the taken solution (PBS solution containing the drug) was measured to investigate the drug sustained-release rule.
As shown in fig. 3, the release process of the drug can be divided into three stages, wherein the drug is released quickly in the first stage for 0-72 hours, and the cumulative release rate reaches 31%; the second stage is a zero-order release stage of the drug within 72-450 hours, and the cumulative release rate of the drug reaches 53%; the third stage of drug release is 450 hours later, the drug release rate begins to slow down, and finally reaches equilibrium in 504 hours, and the cumulative release rate is 56%; the slow release of the medicine can be obtained, and the medicine finally tends to be stable and has long-acting slow release effect.
EXAMPLE 8 animal experiments on corneal graft rejection
SD rats subjected to corneal transplantation were randomly divided into 2 groups of 30 animals each, one experimental group in which the triptolide ophthalmic material prepared in example 1 was immediately implanted after surgery, and one control group to which physiological saline was added. And observing with slit lamp microscope for 1 time every 2 days from 3 days after operation, observing corneal rejection with corneal transparency, edema degree, and neovascularization degree as indexes, killing 3 rats per group 2 weeks after operation, taking eyeball, performing HE staining, and observing neovascularization condition.
As shown in fig. 4, the left graph is the result graph of the control group, the right graph is the result graph of the experimental group, and the eyeballs of the mice are observed, compared with the control group, the neogenesis blood vessels of the palpebral conjunctiva and the bulbar conjunctiva of the experimental group are reduced, so that the slow-release triptolide of the material plays a role in exerting the drug effect, and the corneal transplantation rejection of the mice is improved.
The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.