Multimodal Qdot Based Nanoprobe for Real Time Noninvasive Bioimaging

该提案是响应纳米尺度科学与工程计划，NSF 04-043，类别NIRT而收到的。在许多组织中，特别是肌肉细胞和肝细胞，干细胞被从各自的小生境中招募，以重新填充或与现有细胞融合。然而，确切的细胞信号和有利于细胞靶向和融合的条件目前尚不清楚。这个高风险的建议是开发基于多模态量子点的纳米探针，这种探针具有光学活性，可以跟踪细胞传递，并在标记干细胞与表达β -半乳糖的组织融合时进一步发挥作用，以产生MR对比。纳米探针将被设计成在近红外激发和发射，避免由高频辐射引起的细胞损伤，并在身体组织中提供良好的透射，并在近红外和磁共振成像时提供高对比度，避免有毒金属离子的浸出，并提供灵活性的功能化。多模态Qdots将提供革命性的、超灵敏的（单细胞水平）生物成像能力，这将有助于解开干细胞归巢机制的奥秘，并为理解基因表达机制奠定坚实的基础。拟议的工作将与本科课程相关联，例如粒子科学暑期学校和本科生研究经验课程，该课程将根据拟议的工作分别为专家和研究生提供高级研讨会，并为本科生提供研究经验。将开始每月举办一系列研讨会，向包括专业人士在内的广大社区开放。

This proposal was received in response to Nanoscale Science and Engineering initiative, NSF 04-043, category NIRT. In a number of tissues, and particularly muscle and liver cells, stem cells are known to be recruited from their respective niches to repopulate or fuse with existent cells. However, the exact cellular signal and conditions that favor cell targeting and fusion are currently not well understood. This high risk proposal is to develop multimodal Qdot-based nanoprobes that are optically active to track cell delivery and are further acted upon when a labeled stem cell fuses with tissue expressing beta-galactose, to generate MR contrast. The nanoprobe will be engineered to both be excited by and emit in the near infrared, avoiding cell damage caused by higher frequency radiation and providing good transmission through bodily tissues, and to give high contrast during near infrared and magnetic resonance imaging, avoid the leaching of toxic metal ions, and provide flexibility of functionalization. Multimodal Qdots will offer the possibility of a revolutionary, ultra-sensitive (at the level of a single cell) bioimaging capability which will help to unravel the mystery of stem cell homing mechanisms and develop a strong foundation for understanding gene expression mechanisms.The proposed work will be linked to undergraduate programs, such as the Summer School in Particle Science and Research Experiences for Undergraduates programs, which will provide advanced seminars for experts and graduate students and research experiences for undergraduate students, respectively, based on the proposed work. A monthly seminar series will be started that will be open to the broad community, including professionals.