Time-gated confocal Raman microscope

描述（由申请人提供）：生命科学的进步依赖于新工具和仪器的发展。成像技术能够提供生物体内的结构和化学信息，这极大地提高了我们在细胞和分子水平上理解生命系统功能的能力。拉曼光谱是真正的无创，它可以提供生物组织的化学成分和物理结构的重要信息。这项小规模（R03）研究计划旨在开发一种创新的非侵入性显微光谱学方法，以明确地探索细胞和组织中化学成分的变化。为了实现这一目标，PI将利用时间门控拉曼成像的概念，首次应用于显微镜，以实现对荧光背景具有卓越辨别的共聚焦成像。预计它将在信噪比方面提供至少一个数量级的改进，从而转化为至少100倍的采集速率，同时提高空间分辨率并消除在解决复杂拉曼波段时可能存在的歧义。第一个具体目标是建立一种新型仪器的原型并表征其性能。第二个具体目标是对一种用于分子、细胞和组织成像的新仪器进行试点测试，用于几种模型系统：1)胶原自组织和结构转化，导致骨结构发育；2)视网膜色素上皮细胞的光降解，被认为是失明的主要原因；3)牙齿组织中的早期龋齿检测。许多医学研究和诊断应用需要微创的显微分子成像。拉曼显微光谱学作为一种非侵入性的、化学特异性的分子成像技术，由于强荧光背景，大大降低了信噪比，使其难以揭示振动带的精细结构，因此存在显著的缺点。本研究通过在特殊设计的光学结构中对有用信号进行时间门控，为显微成像提供了解决这一问题的方法。

DESCRIPTION (provided by applicant): Progress in the Life Sciences depends upon the development of new tools and instruments. Our ability to understand the function of living systems on a cellular and molecular level is greatly enhanced by imaging techniques capable of providing structural and chemical information in vivo. Raman spectroscopy is truly non-invasive, and it could provide significant information on the chemical composition and physical structure of biological tissues. This small-scale (R03) research proposal aims to develop an innovative approach for non-invasive microspectroscopy in order to unambiguously explore changes in chemical composition in cells and tissues. To achieve this goal, the PI will utilize the concept of time-gated Raman imaging, applied for the first time to microscopy to achieve confocal imaging with superior discrimination against the fluorescence background. It is expected that it will provide at least an order of magnitude improvement in the signal-to-noise ratio, which transforms into at least 100 times faster acquisition rates, while improving spatial resolution and eradicating possible ambiguities in resolving complex Raman bands. The first specific aim is building the prototype of a novel instrument and characterizing its performance. The second specific aim is pilot testing of a new instrument for molecular, cellular and tissue imaging for several model systems: 1) collagen self-organization and structural transformation, which leads to bone structure development, 2) photodegradation of retinal pigment epithelium cells, which is considered to be the major cause of blindness, and 3) early caries detection in dental tissues. Many medical research and diagnostic applications require microscopic molecular imaging with minimum invasiveness. Raman microspectroscopy, being a non-invasive, chemically specific technique for molecular imaging, suffers a dramatic drawback due to a strong fluorescent background, which significantly reduces the signal-to-noise ratio and makes it difficult to reveal the fine structure of vibrational bands. The proposed research provides a solution to this problem for microscopic imaging by time-gating the useful signal in a specially designed optical arrangement.