ULTRAFAST MULTIPHOTON LASER ACTIVATION SYSTEM

这项提案的目标是创建一个超快多光子激光激活系统。这个集成的激光仪器系统将被组装起来，以支持由多光子光化学和光物理实施的一系列创新的生物医学和生物技术研究计划。锁模激光产生的超快(约100飞秒)脉冲允许同时吸收来自明亮脉冲照明的两个或更多光子，用于分子激发，如用于活体组织生物医学研究的多光子激光扫描荧光显微镜。然而，多光子激发的研究正在为分子生物学和生物医学的研究和诊断提供强大的光化学工具。特别是，特定基因的DNA与相应的调控蛋白的多光子光化学交联可以分析这些基因表达的基本调控因子的分子生物学，并识别每一种特定的调控酶-DNA配对。所提出的激光系统在紫外线(约250)波长下提供适当的、明亮的、超快的脉冲和脉冲对，以便在体外和体内有效地实现这一交联过程。超快激光系统的高能飞秒脉冲在启用或增强整个项目组所需的从210 nm到3000 nm的广泛范围内提供。超快激光系统的其他用户应用包括：(1)通过多光子光激活开发用于局部微观药理学的笼式试剂和笼式神经递质，(2)通过多光子氧化剂激活组织中的分子来研究疾病中的氧化应激效应，(3)研究生物光损伤机制，(4)几种生物物理技术的发展，以及(5)研究所涉及的所有相关多光子光化学过程的光物理机制。拟议的仪器系统促进了几项生物物理技术的发展，特别是开发了用于生物技术设备的制造三维复杂微流体系统的多光子光化学方法，以及用于增强实施多光子显微镜和用于生物医学内窥镜组织荧光光谱以识别疾病状态的光物理。该仪器系统由一个可调钛：蓝宝石激光振荡器、再生放大器、两个独立可调的光学参数振荡器、倍频谐波发生器、延迟线和相关仪器组成，以满足精选生物医学用户群体的高脉冲能量和异常宽的调谐范围要求，并安全地为生物用户群体提供用户友好的仪器设备。

The objective of this proposal is to create an Ultrafast Multiphoton Laser Activation System. This integrated laser instrument system is to be assembled to support a select set of innovative biomedical and biotechnology research programs that are implemented by multiphoton photochemistry and photophysics. Ultrafast (approximately 100 femtosecond) pulses generated by mode-locked lasers allow simultaneous absorption of two or more photons from bright pulsed illumination for molecular excitation as in the multiphoton laser scanning fluorescence microscopy used in biomedical research in living tissue. However, research on multiphoton excitation is evolving powerful photochemical tools for molecular biology and biomedical research and diagnosis. In particular, multiphoton photochemical crosslinking of the DNA of specific genes to the corresponding regulatory proteins allows assay of the molecular biology of these essential regulators of gene expression and identification of each particular regulatory enzyme-DNA pairing. The proposed laser system provides the appropriate, bright, ultrafast pulses and pulse pairs at ultraviolet (approximately 250) wavelengths to implement efficiently this crosslinking process in vitro and, it is expected, in vivo. The high-energy femtosecond pulses of the Ultrafast Laser System are provided throughout the wide range from 210 nm to 3,000 nm needed to enable or enhance the entire group of projects. Other user's applications of the Ultrafast Laser System include (1) development of caged reagents and caged neurotransmitters for localized micro-pharmacology by multiphoton photoactivation, (2) research on oxidative stress effects in disease by multiphoton oxidant activation of molecules in tissue, (3) investigations of biological photodamage mechanisms, (4) developments of several biophysical technologies, and (5) research on the photophysical mechanisms of all of the relevant multiphoton photochemical processes involved. Several biophysical technology developments are facilitated by the proposed instrument system, in particular, development of a multiphoton photochemical method to fabricate 3-dimensionally complex microfluidic systems for biotechnology devices, and photophysics for enhanced implementation of multiphoton microscopy and for biomedical endoscopic spectroscopy of intrinsic tissue fluorescence to recognize disease states. The instrument system consists of a tunable titanium:sapphire laser oscillator, regenerative amplifier, two independently tunable optical parametric oscillators, harmonic generators for frequency multiplication, delay lines and associated instrumentation in order to encompass the high pulse energy and unusually broad tuning range requirements of the select biomedical user community and to safely provide user friendly instrumentation for the biological user community.