EAGER_IDBR: Development of a Two-Photon Circular Dichroism Spectrometer with Extreme Spectral Capabilities in the far UV (FUV-TPCD)

在过去的三十年中，电子圆二色谱（ECD）光谱已成为研究溶液和界面处光学活性生物分子（如蛋白质、核酸和神经递质）的构象和物理化学性质的标准技术。该方法提出了重要的内在局限性的手性分子在溶液中的研究，并在非均匀介质中的远紫外（FUV），光谱区域，其中重要的结构/构象信息可以得到。在FUV中，标准水性缓冲溶液和普通溶剂的单光子吸收（OPA）以及不均匀样品中存在的散射掩盖了手性分子的ECD信号，干扰了关键信息的获取。为了克服现有的障碍，人们提出了一种基于双光子吸收（TPA）的类似非线性方法，即双光子圆二色性（TPCD）。新型TPCD光谱仪在FUV（FUV-TPCD）光谱能力的发展将有助于扩大重要的手性生物分子和大分子（氨基酸，核苷酸，神经递质，肽，蛋白质和核酸），它们的相互作用，动态变化和基本过程中的作用模式的理解前所未有的。此外，FUV-TPCD可以帮助化学家和工程师理解光学活性不对称催化剂和新型手性超材料等的性质。为了履行国家科学基金会的使命，该项目考虑培训研究生和本科生，以及向佛罗里达中部地区的高中学生和教师推广物理科学。该项目还通过代表性不足的群体成员，即三名女性和两名西班牙裔成员的具体参与来促进包容性。 该项目的主要目标是将TPCD光谱仪的光谱能力扩展到FUV，并为开发全自动，紧凑和强大的FUV-TPCD光谱仪奠定基础，该光谱仪将允许在现有ECD光谱仪无法到达的电磁波谱区域中对关键手性生物系统进行结构和构象分析。为了验证FUV中的拟定仪器，将使用四种主要芳香族氨基酸（色氨酸、苯丙氨酸、组氨酸和酪氨酸）作为模型化合物。我们的主要目标背后的基本原理是，桌面FUV-TPCD光谱仪的开发和评估将为构建全自动，紧凑和强大的光谱仪奠定基础，该光谱仪可以在其他实验室中商业化和实施，从而使生物学，化学，光学和纳米科学的科学家广泛接触。传播将通过以下方式完成：向专门从事循环二分法的领先公司的代表提供设施图尔斯参观、在FUV-TPCD中开发新的维基教科书、在国家和国际会议上进行演示以及通过科学出版物、创建一个独特的工具、通过合作向佛罗里达中部的潜在用户开放访问，以及使用外展计划（BIOTEC）接触佛罗里达中部的普通公众。 该奖项由生物基础设施部（董事会：生物学）的生物研究计划（IDBR）和化学部（董事会：数学和物理科学）的化学测量和成像计划（CMI）联合颁发。

During the last three decades electronic circular dichroism (ECD) spectroscopy has been the standard technique for the study of the conformational and physicochemical properties of optically active biomolecules such as proteins, nucleic acids and neurotransmitters, in solutions and at interfaces. The method presents important intrinsic limitations for the study of chiral molecules in solution and in inhomogeneous media in the far UV (FUV), a spectral region where important structural/conformational information can be obtained. In the FUV, the one-photon absorption (OPA) of standard aqueous buffer solutions and common solvents and the scattering present in inhomogeneous samples mask the ECD signal of chiral molecules, interfering with the acquisition of key information. In order to surmount the existent barriers, an analogous nonlinear approach based on two-photon absorption (TPA) has been proposed, i.e. two-photon circular dichroism (TPCD). The development of the novel TPCD spectrometer with spectral capability in the FUV (FUV-TPCD) will help expand the understanding of vital chiral biological molecules and macromolecules (amino acids, nucleotides, neurotransmitters, peptides, proteins, and nucleic acids), their interactions, dynamic changes, and mode of action in fundamental processes as never before. In addition, FUV-TPCD could assist chemist and engineers in the understanding of the properties of optically active asymmetric catalysts and novel chiral metamaterials, among others. Fulfilling the NSF mission, this project contemplates the training of graduate and undergraduate students, as well as the promotion of physical sciences to high school students and teachers in the central Florida area. This project also promotes inclusiveness through the specific involvement of members of underrepresented groups, i.e. three females and two Hispanics. The main goal of this project is to expand the spectral capability of the TPCD spectrometer down to the FUV and set the bases for the development of a fully automated, compact, and robust FUV-TPCD spectrometer that would allow to perform structural and conformational analysis of key chiral biological systems in a region of the electromagnetic spectrum inaccessible by existent ECD spectrometers. To validate the proposed instrument in the FUV, the four main aromatic amino acids (Tryptophan, Phenylalanine, Histidine and Tyrosine) will be used as model compounds. The rationale behind our primary goal is that the development and assessment of a tabletop FUV-TPCD spectrometer will set the bases for the construction of a fully automated, compact and robust spectrometer that could be commercialized and implemented in other labs, thus becoming accessible to a broad community of scientists in biology, chemistry, optics and nanosciences. Dissemination will be accomplished through facility tours offered to representatives of leader companies specialized in circular dichorism, development of new Wikibooks in FUV-TPCD, presentations at national and international meetings and through scientific publications, creating a unique instrument, open-access to potential users in central Florida through collaborations, and using the outreach program (BIOTEC) to reach the general public in central Florida. This award is made jointly by the Instrument Development for Biological Research program (IDBR) in the Division of Biological Infrastructure (Directorate: Biology) and the Chemical Measurements and Imaging program (CMI) in the Division of Chemistry (Directorate: Math and Physical Sciences).