ANS AND TRYPTOPHAN AND PHOTOPHYSICS: SUPERSONIC JET STU

ANS 和色氨酸和光物理学：超音速喷射 STU

• 批准号: 3281908
• 负责人: MARK A SULKES
• 金额: $ 9.07万
• 依托单位: TULANE UNIVERSITY OF LOUISIANA
• 依托单位国家: 美国
• 财政年份: 1985
• 资助国家: 美国
• 起止时间: 1985-09-05 至 1988-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3281908
• 关键词: conformation; electronic spectra; fluorescence spectrometry; fluorescent dye /probe; laser spectrometry; mathematical model; naphthalenes; phase change; photochemistry; tryptophan; tryptophan analog; water solution

The photophysics of arylaminonaphthalene sulfonate (ANS) and tryptophan molecules, in bare molecule and partially solvated forms, will be studied. Supersonic expansion techniques will be used to prepare the samples and laser spectroscopic techniques employed to study them. The principal methods of spectroscopy to be used are pulsed, tunable laser fluorescence excitiaton scans; dispersed fluoresecence of specific features excited; and fluorescence lifetime measurements of specific excited state features, the latter carried out using a synchronously pumped dye laser and time-correlated photon counting. In biological systems ANS derivatives can be used as extrinsic fluorescence probes and tryptophan as a intrinsic one. The photophysics of these molecules is not, however, fully understood. In both cases there have been experimental advances in recent years, primarily involving lifetime measurements in solution environments, and photophysical hypotheses have been refined for each class of molecules. In ANS-type molecules a charge transfer state, facilitated by solvents such as water, appears to be of primary importance; in tryptophan, important effects might arise from molecular conformation, energetically close excited states, and solvent effects on the amino and carboxyl groups. Supersonic expansions can address questions on a molecular scale of interaction; condensed phase experiments cannot offer this possibility. First, the photophysics of bare single molecules will be studied. In particular, control of rotameric conformation of bare tryptophan derivatives should be possible, a potentially powerful tool in studying tryptophan photophysics. Next, ANS and tryptophan derivatives will be complexed with selected solvent molecules, such as water. Spectroscopic bands from different sized complexes will be identified and selectively laser excited for studies of emission properties. In the process of carrying out this work, refinements will be attempted for resolving and characterizing spectroscopic bands from partially solvated complexes with larger numbers of addends. These advances will enable additional solvation studies to proceed on ANS and tryptophan, as well as on other biophysically interesting molecules. The long-term objective is to develop and confirm a complete picture of the photophysics of these systems. It is hoped that, with such an understanding, the influence of environment and bonding on the fluorescent probes' responses can be given a more detailed and correct interpretation.

芳基氨基萘磺酸盐 (ANS) 和色氨酸的光物理学 将研究裸分子和部分溶剂化形式的分子。 将使用超音速膨胀技术来制备样品和 用于研究它们的激光光谱技术。 校长 使用的光谱方法是脉冲、可调谐激光荧光 兴奋扫描；激发特定特征的分散荧光；和 特定激发态特征的荧光寿命测量， 后者使用同步泵浦染料激光器进行 时间相关光子计数。 在生物系统中，ANS 衍生物可以 用作外源荧光探针，色氨酸用作内源荧光探针 一。 然而，这些分子的光物理学并不完全 明白了。 在这两种情况下，最近都取得了实验性进展 年，主要涉及解决方案环境中的寿命测量， 光物理假设已针对每一类进行了完善 分子。 在 ANS 型分子中，电荷转移状态由以下因素促进 水等溶剂似乎是最重要的；在色氨酸中， 分子构象可能会产生重要的影响 接近激发态以及溶剂对氨基和羧基的影响 组。 超音速膨胀可以解决分子尺度的问题 互动；凝聚相实验无法提供这种可能性。 首先，将研究裸单分子的光物理学。 在 特别是，控制裸色氨酸的旋转异构体构象 衍生品应该是可能的，一个潜在的强大的研究工具 色氨酸光物理学。 接下来，ANS和色氨酸衍生物将被 与选定的溶剂分子（例如水）络合。 光谱 来自不同大小复合物的条带将被识别并选择性地 激光激发用于研究发射特性。 在这个过程中 开展这项工作，将尝试解决和完善 表征部分溶剂化配合物的光谱带 更多数量的加数。 这些进步将实现额外的解决方案 继续进行 ANS 和色氨酸以及其他生物物理研究 有趣的分子。 长期目标是制定并确认 这些系统的光物理学的全貌。 希望， 有了这样的认识，环境和联系对 荧光探针的反应可以给出更详细和正确的 解释。