Near-Field IR Microscope For Nanoscale Chemical Imaging

用于纳米级化学成像的近场红外显微镜

• 批准号: 7008756
• 负责人: Gilbert C. Walker
• 金额: $ 13.15万
• 依托单位: UNIVERSITY OF TORONTO
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-04-01 至 2007-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7008756
• 关键词: atomic absorption spectrometry; atomic force microscopy; bioengineering /biomedical engineering; bioimaging /biomedical imaging; biomedical equipment development; chemical structure; high throughput technology; homopeptide; infrared radiation; nanotechnology; optics; polymers; protein structure

DESCRIPTION (provided by applicant): The goal of this project is to develop an attachment for a scanning probe microscope that enables high throughput, apertureless, near field infrared microscopy (ANSIM). The development of this instrument will enable sensing applications that require the characterization of extremely small regions of complex biological materials on surfaces. The proposed near field instrument will be able to perform IR absorption spectroscopy at less than 100nm lateral spatial resolution. The ANSIM attachment will be designed to be small and portable, so that replicas of this attachment may become a practical add-on to other atomic force microscopes (AFMs). The instrument development program has three principal elements. First, infrared (IR) quantum cascade laser arrays will be assembled with the optics for guiding the IR laser light into and out of the microscope. Second, multi-channel detection and signal processing modules will be built and integrated with a common, commercial instrument. Third, improved designs of the sharp metal tip used in an apertureless near-field scanning infrared microscopes will be tested and optimized. IR spectroscopic chemical imaging of manmade polymeric surfaces at 100nm lateral resolution using apertureless near field microscopy has already been demonstrated in preliminary work. The goal of this exploratory proposal is to determine whether useful information can be acquired for imaging biological molecules, and whether technology that would be readily used by other scientists can be developed. The test measurements will concentrate on imaging peptide layers and their secondary structure, primarily using IR active amide bands. This would be the first time IR near field microscopy has been applied to peptide and protein analysis, and would represent a significant step forward in biochemical imaging using scanning probe microscopy. Polyglutamine (PG) and its aggregates have been chosen for demonstration studies because 1) PG has a relatively simple IR spectrum related to its secondary structure and 2) PG structures have been implicated in diseases associated with the deposition of insoluble aggregations of proteins, known as fibrils, in various human organs. To treat or to prevent such diseases, improved ability to observe the formation and the deposition of such insoluble aggregates is required; IR near field microscopy could have considerable impact in this area.

描述（由申请人提供）：该项目的目的是为扫描探针显微镜开发一个附件，该探针显微镜可以使高吞吐量，无言，近乎野外红外显微镜（ANSIM）。 该仪器的开发将实现需要表征非常小的复杂生物材料区域的传感应用。 所提出的近场仪器将能够在小于100nm的侧面空间分辨率下执行IR吸收光谱。 ANSIM附件将设计为小且便携，因此该附件的复制品可能成为其他原子力显微镜（AFMS）的实用附加组件。仪器开发计划有三个主要要素。 首先，红外（IR）量子级联激光阵列将与光学元件组装在一起，以引导IR激光进入显微镜。 其次，将与通用商业仪器建立并集成多通道检测和信号处理模块。 第三，将测试和优化的无斑场扫描红外显微镜的尖锐金属尖端的改进设计。 在初步工作中，已经证明了使用近距离显微镜的横向分辨率在100nm横向分辨率下进行人造聚合物表面的红外光谱学成像。 该探索性建议的目的是确定是否可以获取有用的信息来成像生物分子，以及是否可以开发其他科学家会轻易使用的技术。 测试测量将集中于成像肽层及其二级结构，主要使用IR活性酰胺带。 这将是IR近场显微镜首次应用于肽和蛋白质分析，并且使用扫描探针显微镜在生化成像中迈出了重要一步。聚谷氨酰胺（PG）及其聚集体已被选择进行示范研究，因为1）PG具有与其二级结构相关的相对简单的IR光谱，并且2）PG结构与与蛋白质不溶性的沉积相关的疾病与蛋白质不溶性的沉积相关，在各种人类的Organ中，被称为纤维蛋白。 为了治疗或预防此类疾病，需要提高观察形成和沉积这种不溶性骨料的能力； IR近场显微镜可能在该区域产生相当大的影响。