3次元組織培養における局所環境制御のためのハイドロゲルシステムの開発

我的研究重点是开发各种纳米粒子系统，这些系统可以被引入到商业水凝胶中，以调整它们的性质。我和一位合作者一起开发了一种用功能性聚合物涂覆大珠子的方法，这项研究发表在《胶体与界面科学通讯》上。这种方法需要精确控制颗粒的表面，描述这种表面反应的第二篇文章目前正在准备中。然后，我用这种方法制备了对基质金属蛋白酶9 （MMP-9）有反应的明胶包被珠，这种酶在多种疾病中起着重要作用。该计划是在2022财年使用这些微珠开发MMP-9生物传感器。我开发的另一个纳米粒子系统是基于金纳米棒和DNA，用于酶的靶向释放。金纳米棒可以使用红色激光非常有效地加热，并将产生的健康转移到周围环境中。当双链DNA固定在杆状细胞表面时，细菌会导致DNA融化并释放其中一条链。我用荧光团标记的DNA证实了这个过程，下一步将使用酶标记的DNA。最后，我还开发了一种装载Ca2+离子的脂质体，它可以在温度超过40℃时释放它们的货物。Ca2+离子的增加可以引起一些水凝胶的物理变化，例如海藻酸盐凝胶的硬度增加。为了选择性地保护脂质体，在脂质体的磷脂双分子层中嵌入了小的（4nm）金颗粒。

The focus of my research was the development of various nanoparticle systems that could be introduced into commercial hydrogels to tune their properties. Together with a collaborator, I developed a method to coat large beads with functional polymers, a study that was published on Colloid and Interface Science Communications. Such a method required a precise control of the particles’ surface, and a second article that describes this surface reaction is currently under preparation. I then used this method to prepare gelatin-coated beads that are responsive to matrix metalloproteinase 9 (MMP-9), an enzyme that plays an important role in various diseases. The plan is to use these beads to develop a MMP-9 biosensor in FY22.Another nanoparticle system that I developed was based on gold nanorods and DNA, for the targeted release of enzymes. Gold nanorods can very efficiently heated using a red laser, and the resulting heath is transferred to the surrounding environment. When double strands of DNA are immobilized on the rods’ surface, the heath causes DNA melting and release of one strand. I confirmed this process using fluorophore-labelled DNA, the next step will be using an enzyme-labelled DNA. Finally, I also developed a liposomes loaded with Ca2+ ions, which could release their cargo when the temperature is above 40 C. An increase of Ca2+ ions can cause physical changes in some hydrogels, for example an increase in stiffness of alginate gels. In order to selectively heath only the liposomes, small (4 nm) gold particles were embedded in their phospholipid bilayer.