State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian, People's Republic of China.
J Drug Target. 2009 May;17(4):286-93. doi: 10.1080/10611860902737912.
The present study was intended to develop poly(D,L-lactide-co-glycolide) (PLGA; 50:50, 0.15 dL/g) microspheres (MS) loaded with yuanhuacine (YHC) for passive targeting in lung as well as providing a simple evaluation method for the targeting efficiency of MS. A kind of photochromic spiropyran dye was applied to label MS to clearly demonstrate the in vivo distribution characteristics through intravenous injection into mice and rabbits. Sections of 10-microm thickness from different organs were cut using a microtome, and fluorescent microscopy was used to determine the biodistribution of the MS. The average particle size of MS was 9.0 microm, and the glass transition temperature was 37-40 degrees C. In vitro, the cumulative release achieved 50.8% in 24 h. Histological sections from different organs indicated that the amount of MS in lung achieved maximum in 6 h, as about 8 times as in liver and 70 times higher than the average concentration of other organs. In vivo, MS were gradually swelled and drug concentration remained just 10% in 12 h, which would not result in long time embolization in the lung. This evaluation method supplies a simple and visualized channel in focus for the targeting efficiency of PLGA MS.
本研究旨在制备载芫花素（YHC）的聚（D，L-丙交酯-共-乙交酯）（PLGA；50：50，0.15 dL/g）微球（MS），以被动靶向肺部，并提供一种简单的方法来评价 MS 的靶向效率。一种光致变色螺吡喃染料被应用于标记 MS，以便通过静脉注射到小鼠和兔体内，通过荧光显微镜清楚地显示其体内分布特征。使用切片机从不同器官切取 10 微米厚的切片，通过荧光显微镜确定 MS 的生物分布。MS 的平均粒径为 9.0 微米，玻璃化转变温度为 37-40 摄氏度。体外，在 24 小时内累积释放达到 50.8%。来自不同器官的组织学切片表明，MS 在肺中的含量在 6 小时达到最大值，约为肝脏的 8 倍，是其他器官平均浓度的 70 倍。体内，MS 逐渐肿胀，12 小时内药物浓度仅为 10%，不会在肺部造成长时间栓塞。这种评价方法为 PLGA MS 的靶向效率提供了一种简单直观的聚焦通道。
