硼酸盐缓冲液制备尿酸酶复合脂质体及尿酸酶的特性

Preparation and characterization of uricase in uricase-catalase liposomes prepared using borate buffer

目的研究硼酸-硼砂缓冲液制备的尿酸酶-过氧化氢酶脂质体(BUCLP)中尿酸酶的体外特性。方法采用逆向蒸发法制备BUCLP,并考察其部分理化性质特性。结果 BUCLP中尿酸酶最适温度保持在40℃,最适p H值由8.5降为8.0,而Km值也由14.207μmol/L降为13.623μmol/L;尿酸酶-过氧化氢酶(UAC)与空白纳米脂质体作用后,再与FITC结合,其荧光强度高于游离UAC与FITC结合的荧光强度,且BUCLP在280 nm处的荧光强度高于游离UAC。结论尿酸酶和过氧化氢酶联合制备成BUCLP后尿酸酶的活性增加。

Objective To characterize the property of uricase loaded in uricase-catalase liposomes （BUCLPs） prepared using borate buffer. Methods BUCLPs were prepared using reverse-phase evaporation, and the physicochemical properties of uricase in the prepared BUCLPs were examined. Results The optimal temperature of BUCLP and URI was 40 ℃, their optimal pH values were 8.0 and 8.5, and their Michaelis-Menten constants were 14.207 μmol/L and 13.623 μmol/L, respectively. Fluorescence intensity of nanoliposome-loaded uricase-catalase that bound to FITC was higher than that of uricase-catalase binding directly with FITC; the fluorescence intensity of BUCLP was higher than that of free uricase-catalase at 280 nm. Conclusion Uricase activity is enhanced after loading in uricase and catalase liposomes.