Study On The Acyclovir Palmitate-Loaded Submicron Emulsion

Acyclovir palmitate(ACVP) was synthesized from acyclovir(ACV) and palmitoyl chloride. The final product was identified as ACVP using UV, IR and ~1H-NMR.The purity is 99.21% and the melting point is 225.15℃, determined by HPLC and DSC respectively.HPLC method was developed for the assay of ACVP. The solubility of ACVP in different medium and apparent oil/water partition coefficient were determined by HPLC. ACVP showed its well stability by the results of the experiments in high temperature, humidity and strong light studies.The method of high-pressure homogenization was applied to prepare ACVP intravenous submicron emulsion. The oil phase was selected, and the ratio of the emulsifiers and the dosage of sodium oleate were optimized. The adding mode of soybean lecithin was studied, and the effects of pH values, nitrogen protection and sterilization condition were also detected. Simultaneously, the effects of homogenization pressure and times on the particle size and stability of submicron emulsion were investigated. The results showed that the mean size was about 200nm and the pH was 7.0~7.5。The physicochemical properties such as particle size, zeta potential, pH values, and yield of ACVP intravenous submicron emulsion were studied. The ACVP intravenous submicron emulsion was safe within 10 hours after compatibility test with glucose injection (5%) and sodium chloride injection (0.9%). Simultaneously, ACVP intravenous submicron emulsion was stable through affecting factors testing, accelerated and long-term testing for 3 months respectively.Freeze-dried submicron emulsion was prepared. The optimal freeze-drying process and formulation were selected, and the physicochemical properties before and after...