尿酸氧化酶纳米脂质体性质初步研究.docVIP

 尿酸氧化酶纳米脂质体性质初步研究# 王娜，张景勍** （重庆医科大学药物高校工程研究中心和生物化学与分子药理学重点实验室，重庆 400042） 5 10 15 摘要：目的 研究脂质体介导的产朊假丝酵母尿酸氧化酶的最适温度、最适 pH、酸碱稳定 性，部分金属离子和有机化合物对酶活力的影响等酶学性质，以及免疫原性。方法 采用逆 向蒸发法制备尿酸氧化酶脂质体，对酶最适温度、最适 pH、酸碱稳定性以及部分金属离子 和有机化合物对酶活力的影响等酶学性质进行了考察。分别以尿酸氧化酶脂质体和尿酸氧化 酶作为抗原免疫大鼠，制备抗尿酸氧化酶血清，通过 ELISA 法进行血清抗尿酸氧化酶抗体效 价检测，比较大鼠体内的免疫原性。结果 尿酸氧化酶脂质体与游离尿酸氧化酶的最适温度 均为 40，但前者的活性明显高于后者。在最适温度下，尿酸氧化酶脂质体的最适 pH 值为 8.0，且尿酸氧化酶脂质体的活性明显高于游离尿酸氧化酶。稳定性实验结果表明，在 pH 稳定性和部分有机化合物对酶活力的影响方面，尿酸氧化酶脂质体的稳定性均明显高于尿酸 氧化酶。免疫原性实验结果表明，以尿酸氧化酶脂质体和尿酸氧化酶为抗原制备的大鼠抗血 清效价分别为 1: 500 和 1: 8000，说明尿酸氧化酶脂质体能有效降低免疫原性。结论 产 朊假丝酵母尿酸氧化酶脂质体的酶学性质明显优于游离酶，免疫原性明显低于游离酶，为该 酶的临床应用提供了实验依据。 关键词：药剂学；尿酸氧化酶；脂质体；酶学性质；免疫原性 中图分类号：R944 20 Preliminary Study on Properties of Urate Oxidase Nanonanoliposomes WANG Na, ZHANG Jingqing (Medicine Engineering Research Center, Chongqing Key Laboratory of Biochemical＆Molecular 25 30 35 40 Pharmacology, Chongqing Medical University, ChongQing 400042) Abstract: Objective To study the optimum temperature, optimum pH, pH stability, effect of various chemical agents on liposomal urate oxidase, and the immunogenicity of liposomal urate oxidase. Methods Urate oxidase nanoliposomes （ UOLP ） were prepared by reverse-phase evaporation method. Its optimum temperature and pH value were detected, and its pH stability and effect of various chemical agents on urate oxidase activity were also found, then it is compared with urate oxidase. The rat antiserum was prepared by inoculating the rat with UOLP and UO. The antibody against UO was measured through indirect ELISA using UOLP or UO as coating antigen to analyze the immunogenicity of UOLP and UO in rats. Results The optimum temperature of UOLP and free urate oxidase were the same as 40℃. The temperature range at which UOLP remained a higher activity was larger than that of free urate oxidase. UOLP did shift the optimal pH of enzyme activity from 8.5 (for free urate oxidase) to 8.0, and the activity of UOLP was significantly higher than free UO. Stability experiments showed, in the