To obtain a kind of convenient oral dosage form of protein, which can be fully absorbed and is efficient and safe, the thymosin-loaded PLA（polylactic acid） microspheres are prepared by the emulsification- solvent ev...To obtain a kind of convenient oral dosage form of protein, which can be fully absorbed and is efficient and safe, the thymosin-loaded PLA（polylactic acid） microspheres are prepared by the emulsification- solvent evaporation method and the orthogonal design is used to optimize the technology of preparation. The form of the medicament microspheres of thymosin are proved by differential thermal analysis （DTA）. The drug content is determined by the Lowry method, and the package ratio of medicament microspheres of thymosin and drug release in vitro are calculated. The results show that the average diameter and encapsulation efficiency of the product prepared according to the optimized formulation are 13. 8 μm and 80. 7%, respectively. The in vitro release behavior within 12 h can be described by the Higuchi equation with T1/2 = 295 rain. There are no significant changes in size distribution and residual drug contents after being stored at 25℃ and 40 ℃ for 90 d, respectively. Due to the fact that its thymosin content and package ratio meet the requirement, and its releasing half life is long, the thymosin-loaded PLA microsohere has a favorable application future.展开更多
This paper reports that the film composed of flower-like ZnO micro-spheres, which consists of nano-sheets, is fab- ricated by chemical bath deposition. By adding hydrogen fluoride （HF） into the reaction solution, wh...This paper reports that the film composed of flower-like ZnO micro-spheres, which consists of nano-sheets, is fab- ricated by chemical bath deposition. By adding hydrogen fluoride （HF） into the reaction solution, which contains zinc nitrate hexahydrate and hexamethylenetetramine, the ZnO crystal growth process is changed and the film composed by ZnO micro-spheres is obtained after keeping the reaction solution at 95 ℃ for 2 h. The morphology, crystal phase and wettahility of the sample axe characterized by scanning electron microscope, x-ray diffraction and contact angle meter, respectively. The results show that the filrrl has the micro-nano compound structure. After modification with heptadecafluorodecyltrimethoxy-silane, the wettability of the film changed from superhydrophilicity to superhydropho-bicity, on which water contact angle and the sliding angle are 154° and less than 5° for 8-μL water droplet, respectively. Additionally, the formation mechanism of the ZnO micro-sphere is also discussed.展开更多
文摘To obtain a kind of convenient oral dosage form of protein, which can be fully absorbed and is efficient and safe, the thymosin-loaded PLA（polylactic acid） microspheres are prepared by the emulsification- solvent evaporation method and the orthogonal design is used to optimize the technology of preparation. The form of the medicament microspheres of thymosin are proved by differential thermal analysis （DTA）. The drug content is determined by the Lowry method, and the package ratio of medicament microspheres of thymosin and drug release in vitro are calculated. The results show that the average diameter and encapsulation efficiency of the product prepared according to the optimized formulation are 13. 8 μm and 80. 7%, respectively. The in vitro release behavior within 12 h can be described by the Higuchi equation with T1/2 = 295 rain. There are no significant changes in size distribution and residual drug contents after being stored at 25℃ and 40 ℃ for 90 d, respectively. Due to the fact that its thymosin content and package ratio meet the requirement, and its releasing half life is long, the thymosin-loaded PLA microsohere has a favorable application future.
基金Project supported by the National Natural Science Foundation of China (Grant No. 50872129)Natural Science Foundation of Anhui Province of China (Grant No. 070414187)
文摘This paper reports that the film composed of flower-like ZnO micro-spheres, which consists of nano-sheets, is fab- ricated by chemical bath deposition. By adding hydrogen fluoride （HF） into the reaction solution, which contains zinc nitrate hexahydrate and hexamethylenetetramine, the ZnO crystal growth process is changed and the film composed by ZnO micro-spheres is obtained after keeping the reaction solution at 95 ℃ for 2 h. The morphology, crystal phase and wettahility of the sample axe characterized by scanning electron microscope, x-ray diffraction and contact angle meter, respectively. The results show that the filrrl has the micro-nano compound structure. After modification with heptadecafluorodecyltrimethoxy-silane, the wettability of the film changed from superhydrophilicity to superhydropho-bicity, on which water contact angle and the sliding angle are 154° and less than 5° for 8-μL water droplet, respectively. Additionally, the formation mechanism of the ZnO micro-sphere is also discussed.
