IIBR Instrumentation: Sub-micrometer Resolution Mass Spectrometry Imaging by Deep-UV Laser Ablation and Post-ionization

路易斯安那州立大学和贝勒大学获得了一个奖项，以开发一种用于成像组织中生物分子的仪器，该仪器使用质谱法，具有高空间分辨率和高质量范围。该仪器简单，低成本，易于使用，将为基础和转化生物学研究的广泛研究人员带来高性能的非靶向生化成像。该仪器将用于组合的采样和成像工作流程，能够定位，识别和量化组织中的生物分子。质谱法在体外成像方法中具有独特的优势，因为它是非靶向的;因此，它能够在没有关于组分的先验信息的情况下检测脂质、代谢物、肽和蛋白质。该仪器解决了亚微米精度的大生物分子电离的关键技术障碍，这对于化合物的细胞定位是必要的。受益于拟议仪器的用户社区包括需要空间定位化合物识别和量化的基础和应用领域的研究人员。基础生物学研究将受益于一种可以分析各种生化类别的仪器。转化研究将受益于一个强大和高度灵敏的仪器，相对较低的成本和易用性将使其成为研究中心，而这些研究中心通常没有这种能力。质谱成像项目将利用STEM教育资源进行高中，本科，研究生和博士后教育和培训。该项目将为参加NSF S-STEM学者计划和路易斯斯托克斯路易斯安那州少数民族参与联盟的学生提供研究机会。机会将提供给本科生研究人员从国家参加路易斯安那州生物医学研究网络夏季研究计划和当地初中和高中科学教师通过路易斯安那州立大学凯恩中心干识字。目前的质谱成像技术需要二次离子质谱法（西姆斯）之间的妥协，使用精确聚焦的离子束成像小分子和基质，辅助激光解吸电离（MALDI），其使用较不聚焦但较温和的激光束来成像大分子。拟议的研究消除了这种空间分辨率和质量范围的妥协，通过使用一个高度集中的深紫外烧蚀激光结合紫外后电离激光器的双激光MALDI（MALDI-2）的需要。该方法利用MALDI对消融组织和基质材料的效应，因此具有MALDI的质量范围和温和电离特性。此外，它使用简单，强大和相对低成本的质谱技术，有可能将仪器的功能带给更多的生物成像研究人员。MALDI-2成像与深紫外激光烧蚀取样相结合，用于液相色谱串联质谱分析。将利用各种社交媒体平台以及传统的出版物和会议介绍方法传播该项目的成果。该网站将与移动终端兼容，并提供仪器运行的照片和视频以及所获得的数据。该网站还将包括说明和协议，示例数据以及仪器控制和分析软件。该项目的预期成果是原型深紫外消融MALDI-2成像质谱仪，空间分辨率为1微米，质量范围大于10，000 Da。该仪器将能够成像的速度，易于样品制备，并易于数据采集，这是与传统的MALDI成像质谱。这个奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

An award is made to Louisiana State University and Baylor University to develop an instrument for imaging biomolecules in tissue that uses mass spectrometry and has both high spatial resolution and high mass range. The instrument is simple, low-cost, and easy to use and will bring high-performance untargeted biochemical imaging to a broad range of researchers in fundamental and translational biological research. This instrument will be used in a combined sampling and imaging workflow with the ability to localize, identify, and quantify biomolecules in tissue. Mass spectrometry has the unique advantage among in vitro imaging methods in that it is un-targeted; thus, it has the capability of detecting lipids, metabolites, peptides and proteins without prior information about the components. This instrument addresses a critical technological barrier of large biomolecule ionization at submicrometer precision that is necessary for cellular localization of compounds. The user community benefiting from the proposed instrument includes researchers in fundamental and applied areas that require spatially localized chemical compound identification and quantification. Basic biological research will benefit from an instrument that can analyze a wide range of biochemical classes. Translational research will benefit from an instrument that is robust and highly sensitive and the relatively low cost and ease of use will bring it to research centers where this capability is not typically found. The mass spectrometry imaging project will leverage STEM education resources for high-school, undergraduate, graduate, and postdoctoral education and training. The project will provide research opportunities for students participating in the NSF S-STEM Scholars program and the Louis Stokes Louisiana Alliance for Minority Participation. Opportunities will be available for undergraduate researchers from the State participating in the Louisiana Biomedical Research Network summer research program and for local middle and high school science teachers through the LSU Cain Center for STEM Literacy.Current mass spectrometry imaging techniques require a compromise between secondary ion mass spectrometry (SIMS) that uses a precisely focused beam of ions to image small molecules and matrix-assisted laser desorption ionization (MALDI) that uses a less-focused but gentler laser beam to image large molecules. The proposed research eliminates the need for this spatial resolution and mass range compromise through the use of a highly focused deep-UV ablation laser combined with an ultraviolet post-ionization laser for two-laser MALDI (MALDI-2). The approach uses the MALDI effect on ablated tissue and matrix material and therefore has the mass range and gentle ionization properties of MALDI. Furthermore, it uses simple, robust, and relatively low-cost mass spectrometry technology that has the potential to bring the capabilities of the instrument to more biological imaging researchers. MALDI-2 imaging is combined with deep-UV laser ablation sampling for liquid chromatography tandem mass spectrometry analysis. The results of the project will be disseminated using a variety of social media platforms as well as traditional methods of publications and conference presentations An online presence will be established through a dedicated website and social media that will post photos, videos, and updates on the instrument. The website will be mobile device compatible and feature photos and videos of the instrument in operation as well as the data obtained. The site will also include instructions and protocols, example data, and instrument control and analysis software. The anticipated outcome of this project is a prototype deep-UV ablation MALDI-2 imaging mass spectrometer with 1 µm spatial resolution and greater than 10,000 Da mass range. The instrument will be capable of imaging with the speed, ease of sample preparation, and ease of data acquisition that is comparable to conventional MALDI imaging mass spectrometry.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.