Search

CN-121987568-A - Difunctional nano medicine-carrying eye drops for xerophthalmia and preparation method thereof

CN121987568ACN 121987568 ACN121987568 ACN 121987568ACN-121987568-A

Abstract

The invention discloses a difunctional nano medicine-carrying eye drop for xerophthalmia and a preparation method thereof, belonging to the fields of pharmaceutical preparation technology and ophthalmic pharmacy. The core of the invention is to construct a composite nanoparticle with a core-shell structure and long-acting adhesion lubrication and targeted controlled drug release functions. The preparation method comprises the following steps of firstly, encapsulating hydrophobic immunosuppressants such as cyclosporine A and the like in biodegradable ă pad ă polymer matrixes such as polylactic acid-glycolic acid copolymer (PLGA) and the like by an emulsification-solvent volatilization method to form drug-loaded polymer nano cores. The invention realizes the cooperative targeting treatment of two key pathological links of unstable tear film and immune inflammation of xerophthalmia by the exquisite integrated design of structure and function, obviously improves the bioavailability of the medicine, reduces the administration frequency and ocular irritation, and provides a more efficient, safer and better-patient-compliance administration scheme for the clinical treatment of xerophthalmia.

Inventors

  • SU GUANYU
  • XU WEIXING
  • WEI ZURONG
  • ZHANG XUAN

Assignees

  • 河南省人民医院

Dates

Publication Date
20260508
Application Date
20260205

Claims (10)

  1. 1. The preparation method of the difunctional nano medicine-carrying eye drops for xerophthalmia is characterized by comprising the following steps: Preparing a drug-loaded polymer nano-core, dissolving a hydrophobic immunosuppressant and a biodegradable polyester polymer in an organic solvent to form an oil phase solution, carrying out high-energy homogenization treatment on the oil phase solution in an aqueous phase solution containing a first emulsifier to form a primary water-in-oil emulsion, then adding the primary emulsion into an external aqueous phase containing a second emulsifier, carrying out high-energy homogenization treatment again to form an oil-in-water (O/W/O) or water-in-oil (W/O/W) double emulsion, finally removing the organic solvent in a reduced-pressure rotary evaporation or continuous stirring mode, and carrying out deposition polarization on the polymer to form a solidified drug-loaded nano-core, and carrying out centrifugation and washing purification; step two, carrying out surface functionalization modification on the drug-carrying polymer nano-cores, dispersing the nano-cores obtained by purification in an activation buffer solution, adding an amination reagent, and reacting for a preset time under the specific pH and temperature conditions to enable the surfaces of the nano-cores to be grafted with primary amino groups so as to form the drug-carrying nano-cores with surface amination; Preparing a core-shell structure dual-function nanoparticle, dissolving a thiolated modified biocompatible mucopolysaccharide in a buffer solution containing a chemical coupling agent, activating carboxyl groups on a molecular chain of the thiolated modified biocompatible mucopolysaccharide, adding the surface-aminated drug-loaded nano-core suspension obtained in the step two into the activated mucopolysaccharide solution, performing a coupling reaction under the protection of light and inert gas, enabling the thiolated mucopolysaccharide to be covalently connected to the surface of the nano-core through an amide bond to form a stable core-shell structure, and performing ultrafiltration or dialysis purification to obtain the dual-function nanoparticle; Preparing a final eye drop preparation, dispersing the core-shell structure dual-function nanoparticle obtained by purification in the step three in a pre-prepared and sterilized aqueous ophthalmic carrier containing a pH buffer pair, an isotonic regulator and a preservative under the aseptic condition, dispersing the mixture uniformly by ultrasonic or high shearing, regulating the drug concentration, the pH value and the osmotic pressure of the final preparation to the ophthalmic standard range, and carrying out aseptic filling.
  2. 2. The method for preparing the bi-functional nano drug-loaded eye drop for dry eye according to claim 1, wherein the hydrophobic immunosuppressant in the first step is cyclosporin a, tacrolimus or sirolimus, the biodegradable polyester polymer is polylactic acid-glycolic acid copolymer (PLGA), polylactic acid (PLA) or Polycaprolactone (PCL), the molecular weight of the biodegradable polyester polymer is in the range of 10,000 to 50,000da, and the molar ratio of lactic acid to glycolic acid is 50:50 to 75:25.
  3. 3. The preparation method of the difunctional nano medicine-carrying eye drops for xerophthalmia according to claim 1 or 2, wherein the organic solvent in the first step is dichloromethane, ethyl acetate or a mixed solvent thereof, the first emulsifier is span 80, the second emulsifier is polyvinyl alcohol (PVA) or poloxamer 188, the high-energy homogenizing treatment adopts a high-pressure homogenizer, the homogenizing pressure is 50-150MPa, or a probe type ultrasonic instrument is adopted, and the ultrasonic power is 200-500W.
  4. 4. The method for preparing the bi-functional nano drug-loaded eye drop for dry eye according to claim 1, wherein the amination reagent in the second step is ethylenediamine or Polyethyleneimine (PEI), the reaction is performed in borate buffer solution with a pH value of 7.5-9.0, the reaction temperature is room temperature, the reaction time is 2-6 hours, and the density of amino groups introduced on the surface of the nano-core through the step is 0.5-5.0 mu mol/mg.
  5. 5. The method for preparing the bi-functional nano drug-loaded eye drop for dry eye according to claim 1, wherein the thiolated modified biocompatible mucopolysaccharide in the third step is thiolated hyaluronic acid (HA-SH) or thiolated chitosan, and the thiolated modification is prepared by reacting hyaluronic acid or chitosan with N-acetylcysteine or cysteamine hydrochloride in the presence of a carbodiimide condensing agent (such as EDC), and the substitution degree of thiol groups on the polymer chain is 5-20%.
  6. 6. The method for preparing the bi-functional nano drug-loaded eye drop for dry eye according to claim 5, wherein the chemical coupling agent in the third step is a combination of 1-ethyl- (3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS), the molar ratio of EDC to carboxyl on HA-SH is (2-5): 1, the molar ratio of NHS to EDC is 0.5:1, the coupling reaction is performed in MES buffer with pH of 5.5-6.5, the reaction temperature is 4 ℃, and the reaction time is 12-24 hours.
  7. 7. The preparation method of the difunctional nano drug-loaded eye drops for xerophthalmia according to claim 1, wherein the pH buffer pair in the fourth step is a phosphate buffer pair or a boric acid-borax buffer pair, the pH value of the final preparation is adjusted to 6.8-7.4, the isotonic regulator is sodium chloride, glycerol or mannitol, the osmolality of the final preparation is adjusted to 280-320mOsm/L, and the preservative is benzalkonium chloride or sodium chlorite stable solution.
  8. 8. The method for preparing a bifunctional nano-drug-loaded eye drop for dry eye according to claim 1, wherein the core-shell structured bifunctional nanoparticles prepared by the method have a final average hydrated particle diameter of 150-350nm, a polydispersity index (PDI) of less than 0.25, and a surface Zeta potential of-15 mV to-35 mV in a buffer solution of ph7.4, as measured by dynamic light scattering.
  9. 9. The preparation method of the difunctional nano drug-loaded eye drop for xerophthalmia according to claim 1, wherein the initial feeding mass ratio of the hydrophobic immunosuppressant to the biodegradable polyester polymer is 1:10-1:20, the mass concentration of the immunosuppressant in the final eye drop is 0.05% -0.1% (w/v), and the mass concentration of the core-shell structure difunctional nanoparticle is 0.5% -2.0% (w/v).
  10. 10. A bifunctional nanodrug-loaded eye drop for dry eye prepared by the method for preparing a bifunctional nanodrug-loaded eye drop for dry eye according to any one of claims 1 to 9, wherein the eye drop comprises an aqueous dispersion phase and a dispersion phase composed of core-shell structured bifunctional nanoparticles having a structure of a solid core composed of biodegradable polyester polymer and internally encapsulating a hydrophobic immunosuppressant, and a hydrated shell composed of thiolated hyaluronic acid molecular chains and connected to the surface of the core through covalent amide bonds, the shell imparting negative surface charge to the nanoparticles and disulfide bond formation ability with ocular surface mucin.

Description

Difunctional nano medicine-carrying eye drops for xerophthalmia and preparation method thereof Technical Field The invention belongs to the technical field of pharmaceutical pharmaceutics, and particularly relates to a preparation method of a difunctional nano medicine-carrying eye drop for xerophthalmia. More particularly, the present invention relates to a nano drug-loaded eye drop for treating dry eye with dual therapeutic functions, and a preparation method thereof. Background Dry eye, also known as keratoconjunctival dryness, is a multi-factor ocular surface disease which is very common worldwide, and its core pathological mechanism involves abnormal tear quality or quantity or abnormal dynamics, leading to the decrease of tear film stability, accompanied by ocular surface inflammatory reaction, tissue injury and nerve paresthesia, eventually causing a series of ocular discomfort symptoms such as dryness, burning sensation, foreign body sensation, vision fluctuation and the like, and can lead to complications such as corneal ulcer, perforation and the like when serious, seriously affecting the life quality of patients. According to the international tear film and ocular surface association dry eye studio second edition report (TFOS DEWS II), the global prevalence of dry eye is between 5% and 50%, and the prevalence of video terminal equipment (VDT) is on an increasing trend year by year with aging population, popularization of the VDT, environmental pollution, and the like. Treatment of dry eye is a complex systematic engineering, and current clinical treatment strategies are managed stepwise mainly depending on the severity of the disease. For mild patients, non-drug treatments such as environmental improvement and ocular habit adjustment are mainly adopted, and artificial tears are used for symptomatic lubrication and moisture preservation. However, artificial tears can only temporarily relieve symptoms, cannot fundamentally solve problems, and frequent use of artificial tears containing preservatives may also cause secondary damage to the ocular surface. For moderately severe dry eye patients, there is often a pronounced immune inflammatory response on the ocular surface, inflammatory cell infiltration, elevated levels of inflammatory cytokines (e.g., IL-1. Beta., TNF-. Alpha.) and the formation of a vicious circle of "tear film instability-ocular surface epithelial damage-inflammatory response". Therefore, on the basis of lubrication and moisture retention, anti-inflammatory drugs must be used in combination to block this core pathological link. Currently, prescribed anti-inflammatory agents approved by the U.S. FDA for the treatment of dry eye are mainly immunosuppressants such as 0.05% cyclosporin A (Cyclosporine A, csA) ophthalmic emulsions (trade name: restasis) and 0.09% cyclosporin A ophthalmic solutions (trade name: cequa), and lymphocyte function-associated antigen-1 (LFA-1) antagonists LIFITEGRAST (trade name: xiidra). Among them, cyclosporin a is a potent calcineurin inhibitor, which can effectively inhibit activation and proliferation of T lymphocytes, thereby down-regulating inflammatory response of ocular surface. However, traditional eye drop formulations based on cyclosporin a face three technical pain points in clinical use that are difficult to overcome: There are a variety of physiological barriers to the eye, including tight junctions of the corneal epithelium, rapid washout and renewal of tears (normally about 16% renewal per minute), and mechanical clearance of blinking actions. This results in a conventional eye drop having an effective residence time on the ocular surface of typically only a few minutes after it has been dropped into the conjunctival sac. Cyclosporin a is a polypeptide drug of relatively large molecular weight (1202.6 Da) and highly hydrophobic (water-soluble <27 μg/mL), which itself is difficult to penetrate the hydrophilic tear film and corneal epithelial barrier. The extremely short residence time adds to the extremely poor permeability, resulting in a final drug loading into the intraocular tissue of less than 5% or even less than 1% of the administered dose. To achieve a therapeutic window concentration, patients need to administer the drug several times daily (typically 2 times/day) and the onset of action is slow, typically requiring 3-6 months of continuous administration to observe significant clinical improvement, which greatly limits the rapid manifestation of their therapeutic effects. The Restasis emulsion sold in the market at present is a milky water-in-oil emulsion, and the oily phase (castor oil) can solubilize CsA, but can often cause obvious adverse reactions such as burning sensation, tingling sensation, foreign body sensation, temporary blurred vision and the like after eye drops. It is counted that up to 17% of patients discontinue treatment due to intolerance of these side effects. Cequa although a nano-micelle technology is used for so