电导率法测定N-三甲基壳聚糖包覆多囊脂质体的包覆效率

Determination of coating efficiency of N-trimethyl chitosan coated multivesicular liposomes with conductivity

目的建立N-三甲基壳聚糖(N-trimethyl chitosan,TMC)含量测定方法,考察TMC包覆多囊脂质体(multivesicular liposomes,MVLs)的包覆效率。方法利用电导率法测定TMC的质量浓度,并对该方法进行线性、精密度和回收率的考察。采用离心法分离游离的TMC与多囊脂质体,计算TMC包覆多囊脂质体的包覆效率,优化TMC包覆质量浓度及孵育时间。结果 TMC质量浓度在0.01～1.00 g.L-1内线性关系良好(r=0.999 7),日内和日间相对标准偏差小于3%(n=5),回收率为98.93%～102.8%(n=5)。TMC包覆质量浓度为5 g.L-1时,孵育12 h,用此方法测定TMC包覆多囊脂质体的包覆效率为23.15%,RSD为4.33%。优化后,最佳TMC包覆质量浓度为5 g.L-1,孵育时间为4 h。结论电导率法可用于测定TMC包覆多囊脂质体的包覆效率。

Objective To establish a method for determining the content of N-trimethyl chitosan（TMC）and estimating the coating efficiency of TMC coated multivesicular liposomes（MVLs）.Methods The content of TMC was determined by means of conductivity,and the linearity,the precision and the recovery of the method were also studied.The centrifugation method was employed to separate the free TMC from the MVLs,and the coating amount of TMC was determined to measure the concentration of TMC in the supernatant.Results A calibrated linear curve of TMC concentration was within 0.01-1.00 g·L-1（r=0.999 7）,and RSD within day and between days was less than 3%（n=5）,its recovery rate was in a range of 98.93%-102.8%（n=5）.The TMC coated MVLs were prepared with 5 g·L-1 of TMC and incubated for 12 h,and the coating efficiency was 23.15% with RSD of 4.33%.The optimum concentration of TMC was 5 g·L-1 and incubation time was 4 h.Conclusion Conductivity may be used for determination of the coating efficiency of TMC coated MVLs.