Preparation And Properties Of Clopidogrel Hydrogen Sulfate Submicron Emulsion

Clopidogrel hydrogen sulfate,belongs to the second generation of thiophenopyridine drugs,was the main treatment and prevention of myocardial infarction,stroke,angina and other arterial thrombotic diseases.Currently available clopidogrel hydrogen sulfate were limited,and were unsuitable for the treatment of acute thrombus due to delayed absorption.In order to solve the problems existing in tablets,study of this developed clopidogrel hydrogen sulfate submicron emulsion for intravenous injection.The main contents of the study included:The preformulation of clopidogrel hydrogen sulfate submicron emulsion.The established method for the determination of clopidogrel hydrogen sulfate was established was sensitive,specific and reproducible.The preliminary stability and physicochemical properties of clopidogrel hydrogen sulfate were also studied.The study on stability showed that clopidogrel hydrogen sulfate was stable to light and acid,but degraded under the basicity,high temperature and oxidation.The results of solubility experiment showed that the solubility of clopidogrel hydrogen sulfate decreased with the increase of pH.Study on preparation technology of clopidogrel hydrogen sulfate phospholipid complex.With the recombination rate as the evaluation index,the reaction temperature,reaction time,solvent species,drug concentration and different proportions of drug and phospholipid were investigated by single factor to screen out the optimum preparation process.The properties of phospholipid complex were investigated by UV,IR,DSC and XRD,and the solubility of phospholipid complex in water,octanol and soybean oil was studied.The results showed that the drug and phospholipid were almost completely combined when ethanol was selected as solvent at the drug concentration of 10 mg/mL,the reaction was conducted at 40℃for 3 h with drug/phospholipid=1:2.The characterization results indicated that no new chemical bond was formed in the phospholipid complex,and the drug and phospholipid were intermolecular forces.After the preparation of the drug into phospholipid complex,its oil-water distribution coefficient increased significantly,and its solubility in oil increased significantly.The formulation and technology of clopidogrel hydrogen sulfate submicron emulsion.The prescription of submicron emulsion and the shear temperature,time and speed,homogeneous pressure,and frequency and temperature were investigated by single factor with particle size,Ke,zeta potential and PDI as evaluation index to screen and optimize the best preparation process.The optimum formulation of clopidogrel hydrogen sulfate submicron emulsion contained 0.5%phospholipid complex（by drug content）,12%soybean oil,1.2%phospholipid,0.5%tween-80,0.05%sodium oleate,2.5%glycerol,and the optimum technology was that the shear temperature was 40℃,shear time 5 min,shear speed 10000rpm,homogenization temperature 20℃,homogenization pressure 800 bar,and homogenization times 6.The clopidogrel hydrogen sulfate submicron emulsion was a white emulsion with a particle size of 160 nm～180 nm,with the zeta potential being-20～-40 mv,the drug content being96%～98%,and the encapsulation rate being 95%～97%and pH being 7.4.Stability of clopidogrel hydrogen sulfate submicron emulsion.The study investigated the stability of clopidogrel hydrogen sulfate submicron emulsion under the condition of being exposed to high temperature,light and freezing for 10 day,and also the stability of submicron emulsion under（6±2）℃and（25±2）℃for 6 months.After 6 months of storage at（6±2）℃and（25±2）℃,the particle size,content,p H and entrapment efficiency of submicron emulsion did not change significantly,indicating that the submicron emulsion had good stability.Pharmacokinetics and tissue distribution of clopidogrel hydrogen sulfate submicron emulsion.Gliclazide was selected as the internal standard to establish UPLC-MS/MS in vivo analysis method to determine the blood concentrations of tablets,injection and submicron emulsion.The method was specific,sensitive and reproducible.The AUC_0-t-t of submicron emulsion group was 73.29 ng/mL.h,which was 5.7 times（12.81 ng/mL.h）and 3.8 times（18.81 ng/mL.h）in the injection group and the tablet group respectively,and the C_maxax of submicron emulsion,injection and tablets were 200.82 ng/mL,20.76 ng/mL and 21.63 ng/mL respectively,indicating that the submicron emulsion could improve the bioavailability of drugs.The results showed that the submicron emulsion was mainly concentrated in the spleen,kidney and heart of the rats,and the injection group was mainly distributed in kidney and spleen tissues of the rats.The preliminary safety evaluation of clopidogrel hydrogen sulfate submicron emulsion.Hemolytic,vascular irritation,subacute toxicity and licking experiment were used to evaluate the safety of submicron emulsion.The experimental results showed that the submicron emulsion did not cause hemolysis and had little irritation to blood vessels and subcutaneous tissues.The HE staining results showed that the submicron emulsion had no obvious toxicity to heart,liver,spleen,lung and kidney tissues,suggesting thatclopidogrel hydrogen sulfate submicron emulsion was safe and safe to use.