Near Threshold Excited State Dynamics in Nucleobases and Related Compounds

核碱基和相关化合物的近阈值激发态动力学

基本信息

批准号：
1800283
负责人：
Mattanjah de Vries
金额：
$ 54.49万
依托单位：
University of California-Santa Barbara
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2018
资助国家：
美国
起止时间：
2018-07-01 至 2022-12-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1800283&HistoricalAwards=false
关键词：
Near Threshold Excited State Dynamics

项目摘要

In this project, funded by the Chemical Structure Dynamics and Mechanism (CSDM-A) program of the Chemistry Division, Prof. de Vries at the University of California Santa Barbara will study how isolated DNA bases respond to ultraviolet (UV) light. Understanding the response of DNA bases to UV radiation is critical for both practical and fundamental reasons. Nucleobase photochemistry following UV absorption constitutes a fundamental step in radiation induced DNA damage. The extremely efficient response of the nucleobases to absorption of ultraviolet light is often described as nature's strategy to protect the building blocks of life against UV photodamage. UV photo-selection may have played a key role in prebiotic chemistry on an early earth. These same processes also find applications in a variety of modern materials. This project will focus on gas phase spectroscopy of nucleobases and their clusters in the picosecond time domain and close to the threshold for absorption. Experiments will study the excited state processes with the isomer specificity afforded by double resonant spectroscopy in the gas phase and in the sub-nanosecond time domain. Collaboration with computational chemists will provide comparison of the results with quantum chemical modeling. Choosing low energy excitation wavelengths will make the work most sensitive to the details of the relaxation processes. This approach will make it possible to directly investigate the key mechanisms of the response of nucleobases to UV irradiation so this research will contribute to the most basic understanding of fundamental processes that govern the molecular building blocks of life. These topics, in combination with cutting-edge laser and computational techniques, lend themselves extraordinary well to outreach activities that will be based in this work, which also provides for the training of both undergraduate and graduate students in the design and construction of advanced experimental instrumentation, complex computer simulation, and conducting fundamental research.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.

在这个项目中，由化学部的化学结构动力学和机制（CSDM-A）计划资助，加利福尼亚大学圣塔芭芭拉大学的De Vries教授将研究孤立的DNA碱基对紫外线（UV）光的反应。由于实际和基本原因，了解DNA碱基对紫外线辐射的响应至关重要。紫外线吸收后的核碱酶光化学构成了辐射诱导DNA损伤的基本步骤。核仁酶对吸收紫外线的极为有效的反应通常被描述为自然保护生命块免受紫外光损伤的策略。紫外线照相选择可能在地球早期益生元化学中发挥了关键作用。这些相同的过程还可以在各种现代材料中找到应用。该项目将集中于核碱基的气相光谱及其在皮秒时间域中的簇，并接近吸收阈值。实验将研究激发状态过程，并在气相和亚纳秒时域中通过双谐振光谱提供的异构体特异性。与计算化学家的合作将提供结果与量子化学建模的比较。选择低能激发波长将使工作对放松过程的细节最敏感。这种方法将可以直接研究核碱基对UV辐射的反应的关键机制，因此这项研究将有助于对控制生命分子构建基础的基本过程的最基本理解。这些主题结合了尖端的激光和计算技术的结合，非常适合将基于这项工作的外展活动，这也提供了在设计和构建高级实验仪器，复杂的计算机模拟以及进行基本研究的高级实验仪器的设计和构建方面的培训，并构建了基本奖。影响审查标准。