In this study, poly (d, l-lactide-co-glycolide) (PLGA) composite microspheres containing anhydrous reverse micelle (R.M.) dipalmitoylphosphatidylcholine (DPPC) nanoparticles loaded vascular endothelial growth factor (VEGF) were produced using microfluidic platforms. The VEGF-loaded R.M. nanoparticles (VRM) were achieved by initial self-assembly and subsequent lipid inversion of the DPPC vesicles. The fabricated VRMs were encapsulated into the PLGA matrix by flow-focusing geometry microfluidic platforms. The encapsulation efficiency, in vitro release profile, and the bioactivity of the produced composite microspheres were investigated. The release study showed that VEGF was slowly released from the PLGA composite microspheres over 28 days with a reduced initial burst (18 ± 4.17% in the first 24 H). The VEGF stability during encapsulation and release period was also investigated, and the results indicated that encapsulated VEGF was well preserved. Also, the bioactivity assay of the PLGA composite microspheres on human umbilical vein endothelial cells was confirmed that the encapsulated VEGF was utterly active. The present monodisperse and controllable VEGF-loaded microspheres with reproducible manner could be widely used in tissue engineering and therapeutic applications.

中文翻译：

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微流体辅助制造反胶束/PLGA 混合微球，用于持续递送血管内皮生长因子

在这项研究中，使用微流体平台生产了含有无水反胶束（RM）二棕榈酰磷脂酰胆碱（DPPC）纳米颗粒的聚（d，l-丙交酯-共-乙交酯）（PLGA）复合微球。载有 VEGF 的 RM 纳米颗粒 (VRM) 是通过 DPPC 囊泡的初始自组装和随后的脂质反转实现的。通过流动聚焦几何微流体平台将制造的 VRM 封装到 PLGA 基质中。包封率，体外释放曲线，并研究了生产的复合微球的生物活性。释放研究表明 VEGF 在 28 天内从 PLGA 复合微球中缓慢释放，初始爆发减少（前 24 小时为 18 ± 4.17%）。还研究了包封和释放期间VEGF的稳定性，结果表明包封的VEGF保存良好。此外，PLGA 复合微球对人脐静脉内皮细胞的生物活性测定证实，封装的 VEGF 是完全有活性的。目前具有可重复方式的单分散和可控的 VEGF 负载微球可广泛用于组织工程和治疗应用。