A Mass Spectrometry Probe for Transient Imaging of In-Solution Biochemistry

描述（由申请人提供）：在生物医学研究中，经常需要检测和监测界面附近溶液中的动态化学物质。例如，许多研究的重点是检测从培养的组织或细胞到周围介质中的化学分泌物。通常，此类应用对检测方法所需的空间和时间分辨率提出了特定要求。当监测分泌物时，这可能是由于细胞类型和行为的异质性，以及细胞活动随时间的变化。标记，例如，荧光标记，放射性标记，或使用抗原/抗体附着，作为成像动态生物化学的基础，已经取得了惊人的成功，但对标记分析物行为改变和非特异性结合的担忧不能消除。此外，所有有针对性的方法，包括那些基于标记的方法，在发现潜力方面都是有限的，因为人们无法找到自己不想找的东西。提出的研究目的是克服当前生化成像技术的固有局限性。这将通过电喷雾离子源的开发来实现，电喷雾离子源可以作为质谱探针（MSP），从生物界面附近的微环境中进行高分辨率的生化检测。该研究团队在发明新型质谱离子源方面取得了成功，并提出，在这个项目中，要完成将样品收集、处理和电离的所有先决条件结合到微采样毛细管中的雄心勃勃的任务。这种“尖端实验室”将包括在线微透析，以去除盐和交换溶剂，以及集成的胰蛋白酶消化微反应器。研究团队将通过建立多方面的方法来开发，优化和演示MSP，结合实验（包括光学和质谱表征），分析和模拟（第一性原理物理模型和计算流体动力学），以及最先进的制造（微加工）。MSP将作为假设发生器在生物学研究中发挥重要作用，并将成为促进再生医学应用生物反应器开发的关键工具。成功的结果有可能对广泛的研究应用带来变革性的好处，包括生物标志物的发现、对健康和病变细胞生物学的更好理解、生物传感器的开发以及生物制造过程的分析和控制。除了在会议上介绍和在档案期刊上发表外，还将通过在Ga举办的教育讲习班传播MSP技术对生物问题的应用。此外，探针将连接到一个TOF质谱仪，该质谱仪是NSF支持的国家纳米技术基础设施网络（NNIN）的一部分，因此可供工业和学术机构的用户使用。

DESCRIPTION (provided by applicant): Quite frequently in biomedical research there is a need to detect and monitor dynamic chemistries in solution in the vicinity of an interface. For instance, many studies focus on detection of chemical secretions from cultured tissues or cells into the surrounding medium. Often, such applications place specific demands on the required spatial and temporal resolution of the detection method. When monitoring secretions this would be due to heterogeneity in the cell types and behavior, and also variation in cellular activities with time. Labeling, with, for instance, a fluorescent marker, a radioactive marker, or using antigen/ antibody attachment, has been spectacularly successful as the foundation for imaging dynamic biochemistry, but concerns about the altering of labeled analyte behavior and non-specific binding cannot be eliminated. Furthermore, all targeted methods, including those based on labeling, are inherently limited in their discovery potential, as one cannot find what one is not looking for. The purpose of the proposed research is to overcome the inherent limitations of current biochemical imaging technologies. This will be done through the development of electrospray ion sources that can serve as mass spectrometry probes (MSP) for highly resolved biochemical detection from the microenvironment adjacent to biological interfaces. The research team has a demonstrated history of success inventing novel mass spectrometry ion sources, and proposes, for this project, to accomplish the ambitious task of combining all prerequisite capabilities for sample collection, processing, and ionization into a micro- sampling capillary. This "lab-on-a-tip" will include in-line microdialysis to remove salts and exchange solvent, as well as an integrated tryptic digestion micro-reactor. The research team will develop, optimize and demonstrate MSP through an established multifaceted approach combining experiment (including optical and mass spec characterization), analysis and simulation (first principles physical models and computational fluid dynamics), and state of the art manufacturing (microfabrication). MSP will assume an important role in biological research as a hypothesis generator, and will become a key tool in improving development of bioreactors for regenerative medicine applications. Successful results have potential for transformational benefits to a wide range of research applications, including biomarker discovery, improved understanding of healthy and diseased cell biology, biosensor development, and bio-manufacturing process analysis and control. In addition to presentation at conferences and publication in archival journals, the application of MSP technology to biological problems will be disseminated through an educational workshop hosted at Ga. Tech. Furthermore, the probe will be coupled to a TOF mass spectrometer that is part of the NSF supported National Nanotechnology Infrastructure Network (NNIN), and therefore available to users from industry and academic institutions alike.