Single Cell Analysis via Nanoscale Tip-Enhanced Laser Ablation Mass Spectrometry

 描述（由申请人提供）：拟议的II期STTR研究的目标是开发一种成像系统，能够以亚细胞空间分辨率检测和识别细胞和组织切片中的生物分子。该系统将原子力显微镜（AFM）与质谱（MS）分析相结合，并利用在研究的第一阶段开发的独特尖端增强激光烧蚀（TELA）方法。目前成像质谱的技术局限性在于，可以获得小分子的高分辨率图像和大分子的低分辨率图像，但不可能同时获得两者。拟议的文书直接解决了这一技术限制。在第一阶段下开发的TELA效应作为离线MS方法将在第二阶段下开发成在线仪器，该在线仪器集成了AFM和质谱成像，以获得优异的空间分辨率和生物分子质谱。该项目的目标分为1）进一步完善TELA和开发在线TELA-MS接口，2）TELA和MS成像的集成，以及3）应用于脑成像。尖端增强激光烧蚀的改进涉及脉冲烧蚀激光和原子力显微镜尖端之间的基本相互作用的研究。优化的消融系统将与超低流量电喷雾电离系统相结合，其中来自电喷雾源的带电粒子与消融羽流相互作用以形成生物分子离子。AFM和MS成像系统的集成将使用四种成像模式：逐点采样，区域采样，区域成像和深度分析。结果是AFM能够对细胞和组织进行物理和化学成像。AFM TELA-MS装置将被应用于大鼠脑组织中生物分子的检测。将对脂质、肽、可卡因和可卡因代谢物进行空间分析。原子力显微镜TELA-MS系统将由Anasys构建，基于过去的产品开发和制造经验与纳米级成像系统，如原子力显微镜和红外光谱化学成像使用可调脉冲激光源。质谱性能测试将在路易斯安那州州立大学的Kermit Murray教授的实验室进行，他是通过质谱检测生物分子的激光消融方法开发方面的专家。

 DESCRIPTION (provided by applicant): The goal of the proposed Phase II STTR research is to develop an imaging system capable of detecting and identifying biomolecules in cells and tissue sections with sub-cellular spatial resolution. The system combines an atomic force microscope (AFM) with mass spectrometry (MS) analysis and utilizes a unique tip-enhanced laser ablation (TELA) method developed in the Phase I portion of the research. The current technology limitation of imaging mass spectrometry is the fact that it is possible to obtain high-resolution images of small molecules and low-resolution images of large molecules, but it is not possible to both at once. The proposed instrument directly addresses this technology limitation. The TELA effect developed under Phase I as an off - line MS method will be developed under Phase II into an on-line instrument that integrates AFM and mass spectrometry imaging for both excellent spatial resolution and biomolecule mass spectrometry. The aims of the project are divided into 1) further refinement of TELA and development of the on-line TELA-MS interface, 2) integration of TELA and MS imaging, and 3) application to brain imaging. Refinement of the tip - enhanced laser ablation involves a study of the fundamental interaction between the pulsed ablation laser and the atomic force microscope tip. The optimized ablation system will be combined with an ultra-low flow electrospray ionization system in which charged particles from the electrospray source interact with the ablation plume to form biomolecule ions. Integration of the AFM and MS imaging systems will use four imaging modalities: spot-by-spot sampling, area sampling, area imaging, and depth profiling. The result is an AFM capable of both physical and chemical imaging of cells and tissue. The AFM TELA-MS device will be applied to detection of biomolecules in rat brain tissue. Spatial profiling of lipids, peptides, cocaine, and cocaine metabolites will be performed. The AFM TELA-MS system will be constructed by Anasys, based on past product development and manufacturing experience with nanoscale imaging systems such as atomic force microscopy and infrared spectroscopy chemical imaging using tunable pulsed laser sources. Mass spectrometry performance tests will be carried out on in the laboratory of Prof. Kermit Murray at Louisiana State University who is an expert in the development of laser ablation methods for the detection of biomolecules by mass spectrometry.