Khang G, Kim S W, Cho J C, Rhee J M, Yoon S C, Lee H B
Department of Polymer Science and Technology, Chonbuk National University, Chonju, Korea.
Biomed Mater Eng. 2001;11(2):89-103.
Biodegradable microspheres were prepared with poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV, 85:15 by mole ratio of hydroxybutyrate to hydroxyvalerate) by an water-in-oil-in-water (W/O/W), oil-in-water (O/W) and oil-in-oil (O/O) solvent evaporation method for the sustained release of anti-cancer drug, 5-fluorouracil (5-FU) with controlling the fabrication conditions. The shape of microspheres prepared was relatively rough due to highly crystalline property of PHBV and spherical. The efficiency of 5-FU loading into the PHBV microsphere with O/O method was over 80% compared to that 7% for microspheres by O/W method and below 1% for microspheres by a conventional W/O/W method. However, the most desirable release pattern can be achieved from the O/W method due to the cosolvent effect. The effects of preparation conditions such as the type and amount of surfactant, initial amount of loaded drug, the temperature of solvent evaporation, and etc. on the morphology for W/O/W method were investigated. Possible mechanisms of the desirable sustained release pattern for O/W system have been proposed.
采用水包油包水（W/O/W）、油包水（O/W）和油包油（O/O）溶剂蒸发法，以聚（3-羟基丁酸酯-co-3-羟基戊酸酯）（PHBV，羟基丁酸酯与羟基戊酸酯的摩尔比为85:15）制备了可生物降解的微球，用于抗癌药物5-氟尿嘧啶（5-FU）的缓释，并对制备条件进行了控制。由于PHBV具有高度结晶性，制备出的微球形状相对粗糙且呈球形。与O/W法制备的微球载药效率7%以及传统W/O/W法制备的微球载药效率低于1%相比，O/O法制备的PHBV微球中5-FU的载药效率超过80%。然而，由于助溶剂效应，O/W法可实现最理想的释放模式。研究了诸如表面活性剂的类型和用量、初始载药量、溶剂蒸发温度等制备条件对W/O/W法微球形态的影响。提出了O/W体系实现理想缓释模式的可能机制。
