静电纺丝的主要参数对PLGA纤维支架形貌和纤维直径的影响

EST(expressed sequence tags,EST)是一段长约150～500bp基因表达的外源序列片段,是由大规模随机挑取的cDNA克隆测序得到的组织或细胞基因组的表达序列标签。一个EST代表生物某一时期的某种组织或细胞的一个表达基因。主要综述了EST技术的原理方法,哺乳动物早期胚胎研究的理论基础以及EST技术在早期胚胎研究方面的应用,并讨论了利用EST进行研究分析的发展趋势。

The influence of several chief parameters in electrospinning on the morphology and the fiber diameter of PLGA fiber scaffolds

To prepare PLGA fiber scaffolds by electrospinning process and investigate the influence of preparation parameters on the structure of the scaffolds. With the compound of THF and DMF as the solvent, the PLGA fiber scaffolds with different surface morphology were fabricated via altering PLGA solution concentration, flowing rate and applied electric field strength. The morphology and diameter of the fibers were observed using a scanning electron microscope (SEM). The biocompatibility of cell-scaffold complex was also evaluated by seeding human dermal fibroblasts onto the PLGA fiber scaffolds, including cell adhesion and proliferation. The results show that the diameter of fibers and the bound of distributing increase with the increase in the concentration of PLGA solution. As the flowing rate increases, the diameter of fibers increases. However, with the increase in the applied electric field strength, no significant difference in the diameter of the fiber can be observed. Furthermore, both the increase in the concentration of PLGA solution and applied electric field strength in the volume range of current investigation can lead to the reduction in the beads formation within the scaffold. The results of in vitro cell culture on the PLGA scaffolds also confirm that the PLGA fiber can support the adhesion and proliferation of huaman dermal fibroblasts.