State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu, China.
J Biomater Appl. 2013 Aug;28(2):288-97. doi: 10.1177/0885328212446097. Epub 2012 May 4.
The corium is decreased to about half of its thickness in skin defects and wrinkles due to gravity and environment. In this study, dexamethasone/poly(d,l-lactic acid) (Mn = 160,000) microspheres were incorporated into poly(ethylene glycol)-poly(ε-caprolactone)-poly(ethylene glycol) (Mn = 3300) hydrogel to prepare an injectable hydrogel composite. The composite was designed to increase the thickness of the corium. Dexamethasone/poly(d,l-lactic acid) microspheres were prepared by oil-in-water emulsion/solvent evaporation technique. The properties of microspheres were investigated by size distribution measurement, scanning electron microscope and x-ray diffraction. Drug loading, encapsulation efficiency, and drug delivery behavior of microspheres were also studied in detail. Cell adhesion of microspheres was investigated by NIH3T3 cell in vitro. The properties of hydrogel composite were investigated by scanning electron microscope, rheological measurements and methyl thiazolyl tetrazolium assay. Drug release from composite was determined by HPLC-UV analysis. These results suggested that poly(d,l-lactic acid) microspheres encapsulating dexamethasone embedded in poly(ethylene glycol)-poly(ε-caprolactone)-poly(ethylene glycol) hydrogel might have prospective application in orthopedic tissue engineering field.
由于重力和环境的影响，真皮在皮肤缺损和皱纹处减少到原来厚度的一半。在这项研究中，将地塞米松/聚（D，L-丙交酯）（Mn = 160,000）微球掺入聚乙二醇-聚（ε-己内酯）-聚乙二醇（Mn = 3300）水凝胶中，制备可注射水凝胶复合材料。该复合材料旨在增加真皮的厚度。地塞米松/聚（D，L-丙交酯）微球采用油包水乳液/溶剂蒸发技术制备。通过粒径分布测量、扫描电子显微镜和 X 射线衍射研究了微球的性能。还详细研究了微球的载药量、包封效率和药物释放行为。通过体外 NIH3T3 细胞研究了微球的细胞黏附性。通过扫描电子显微镜、流变测量和噻唑蓝比色法研究了水凝胶复合材料的性能。通过 HPLC-UV 分析测定了复合材料的药物释放情况。这些结果表明，包埋地塞米松的聚（D，L-丙交酯）微球嵌入聚乙二醇-聚（ε-己内酯）-聚乙二醇水凝胶中可能在骨科组织工程领域具有应用前景。
