The purpose of this study was to develop a PLGA-PEG-COOH- and gelatin-based microparticles (MPs) dual delivery system for release of BMP-2 and IGF-1. We made and characterized the delivery system based on its morphology, loading capacity, Encapsulation efficiency and release kinetics. Second, we examined the effects of electron beam (EB) sterilization on BMP-2 and IGF-1 loaded MPs and their biological effects. Third, we evaluated the synergistic effect of a controlled dual release of BMP-2 and IGF-1 on osteogenesis of MSCs. Encapsulation efficiency of growth factors into gelatin and PLGA-PEG-COOH MPs are in the range of 64.78% to 76.11%. E-beam sterilized growth factor delivery systems were effective in significantly promoting osteogenesis of MSCs, although E-beam sterilization decreased the bioactivity of growth factors in MPs by approximately 22%. BMP-2 release behavior from gelatin MPs/PEG hydrogel shows a faster release (52.7%) than that of IGF-1 from the PLGA-PEG-COOH MPs/PEG hydrogel (27.3%). The results demonstrate that the gelatin and PLGA-PEG-COOH MPs based delivery system could realize temporal release of therapeutic biomolecules by incorporating different growth factors into distinct microparticles. EB sterilization was an accessible method for sterilizing growth factors loaded carriers, which could pave the way for implementing growth factor delivery in clinical applications.

中文翻译：

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PLGA-PEG-COOH 和基于明胶的微粒双重递送系统和电子束灭菌效果的开发，用于控制 BMP-2 和 IGF-1 的释放

本研究的目的是开发一种用于释放 BMP-2 和 IGF-1 的 PLGA-PEG-COOH 和基于明胶的微粒 (MPs) 双重递送系统。我们根据其形态、负载能力、包封效率和释放动力学对递送系统进行了制作和表征。其次，我们检查了电子束 (EB) 灭菌对加载 BMP-2 和 IGF-1 的 MP 的影响及其生物效应。第三，我们评估了 BMP-2 和 IGF-1 的受控双重释放对 MSC 成骨的协同作用。生长因子在明胶和 PLGA-PEG-COOH MP 中的封装效率在 64.78% 到 76.11% 之间。电子束灭菌的生长因子递送系统可有效显着促进 MSCs 的成骨，尽管电子束灭菌使 MP 中生长因子的生物活性降低了约 22%。BMP-2 从明胶 MPs/PEG 水凝胶的释放行为显示出比从 PLGA-PEG-COOH MPs/PEG 水凝胶 (27.3%) 的 IGF-1 更快的释放 (52.7%)。结果表明，基于明胶和 PLGA-PEG-COOH MPs 的递送系统可以通过将不同的生长因子掺入不同的微粒中来实现治疗性生物分子的时间释放。EB 灭菌是一种对负载生长因子的载体进行灭菌的可行方法，可为在临床应用中实施生长因子递送铺平道路。结果表明，基于明胶和 PLGA-PEG-COOH MPs 的递送系统可以通过将不同的生长因子掺入不同的微粒中来实现治疗性生物分子的时间释放。EB 灭菌是一种对负载生长因子的载体进行灭菌的可行方法，可为在临床应用中实施生长因子递送铺平道路。结果表明，基于明胶和 PLGA-PEG-COOH MPs 的递送系统可以通过将不同的生长因子掺入不同的微粒中来实现治疗性生物分子的时间释放。EB 灭菌是一种对负载生长因子的载体进行灭菌的可行方法，可为在临床应用中实施生长因子递送铺平道路。