College of Sciences, Northeastern University, Shenyang 110004, China.
ACS Appl Mater Interfaces. 2020 May 20;12(20):23606-23616. doi: 10.1021/acsami.0c04260. Epub 2020 May 11.
Titanium dioxide (TiO) nanomaterials have attracted much interest in life science and biological fields because of their excellent photocatalytic activity and good biocompatibility. However, owing to its wide band gap, photocatalysis of TiO can be only triggered by UV light. The limited transparent depth of UV light and the generated reactive oxygen species (ROSs) cause inflammation response of skin tissue, thus posing two major challenges in the photocatalytic application of TiO-based materials in drug delivery and other biotechnology fields. Here, we propose an upconversion-related strategy to enable the photocatalytic activity of TiO nanotubes in near-infrared light and apply the system as a controllable drug delivery platform. More importantly, the ROS-induced cytotoxicity and the preleaching of payloads are significantly reduced on the as-proposed amphiphilic TiO nanotubes. The hydrophobic monolayers are served as a "cap" to provide protection for ROS-induced inflammation and long-term storability. This amphiphilic drug delivery system broadens the potential applications of TiO-based nanomaterials in biomedicine.
二氧化钛（TiO）纳米材料因其优异的光催化活性和良好的生物相容性，在生命科学和生物领域引起了广泛关注。然而，由于其宽的带隙，TiO 的光催化作用只能被紫外光触发。紫外光的有限透明深度和产生的活性氧物质（ROSs）引起皮肤组织的炎症反应，因此在基于 TiO 的材料在药物输送和其他生物技术领域的光催化应用中存在两大挑战。在这里，我们提出了一种上转换相关的策略，使 TiO 纳米管在近红外光下具有光催化活性，并将该系统用作可控药物输送平台。更重要的是，所提出的两亲性 TiO 纳米管显著降低了 ROS 诱导的细胞毒性和有效载荷的预浸出。疏水性单层作为“盖子”，为 ROS 诱导的炎症和长期储存提供保护。这种两亲性药物输送系统拓宽了基于 TiO 的纳米材料在生物医学中的潜在应用。
