Development of dynamic hydrogel systems to tune local microenvironement in three dimensional cell culture system

我的研究重点是开发纳米颗粒系统，可以将其引入商业水凝胶中，以调整其性能。我研究过的一种纳米粒子是荧光量子点。要在水凝胶体系中使用这些粒子，必须在生理条件下优化它们的稳定性和光学性质。我进行了一项基础研究，展示了以前发表的文章如何没有严格地研究这些粒子的表面化学。这项研究的结果发表在《ACS应用纳米材料》杂志上，并将在2023年6月的一次会议上发表。我继续开发的另一个纳米颗粒系统是基于金纳米棒和DNA的。当受到红色激光照射时，金纳米棒可以非常有效地产生热量，并将产生的热量传递到周围环境。当双链DNA固定在棒的表面时，热量会导致DNA融化，随后一条DNA释放到周围的介质中。使用荧光标记的DNA证实了这一机制，该计划是使用激光在3D培养的内皮细胞中定向释放生长因子。制备内皮细胞球体，并用于发芽实验，以测试从金DNA颗粒中释放生长因子的情况。还需要更多的测试来充分表征该系统对激光照射的反应以及由此导致的内皮细胞的形态变化。

The focus of my research was the development of nanoparticle systems that could be introduced into commercial hydrogels to tune their properties. One type of nanoparticle that I worked with are fluorescent quantum dots. To use these particles in hydrogel systems, it is essential to optimize their stability and optical properties in physiologically relevant conditions. I conducted a fundamental study, showing how previously published articles did not rigorously investigate the surface chemistry of these particles. The results of this investigation were published in the journal ACS Applied Nano Materials and will be presented to a conference in June 2023.Another nanoparticle system that I continued developing was based on gold nanorods and DNA. Gold nanorods can very efficiently generate heat when irradiated by a red laser, and the resulting heat is transferred to the surrounding environment. When double strands of DNA are immobilized on the rods’ surface, the heat causes DNA melting and subsequent release of one strand into the surrounding media. This mechanism was confirmed using fluorophore-labelled DNA, and the plan was to use a laser for the targeted release of a growth factor in 3D cultures of endothelial cells. Endothelial cells spheroids were produced and used in a sprouting assay to test the release of growth factor from the Gold-DNA particles. More tests will be required to fully characterize the response of this system to laser irradiation and the resulting morphological changes on the endothelial cells.