Optimized Ultraviolet Fluorescence Detection of Biological Chromophores

这项由化学部门颁发给德克萨斯大学奥斯汀分校的启动基金支持了Jason B. Shear教授的研究。本研究的主题是生物发色团的紫外荧光检测。研究了单胺类神经递质的多光子激发降解的机制和程度。比较了在近红外波长范围内使用锁模钛蓝宝石激光器激发三光子神经递质的光破坏量子产率，以及使用频率加倍的钛蓝宝石激光器激发双光子神经递质的光破坏量子产率。评估了两光子和三光子激发荧光测量中的背景源，并将其与光破坏测量相结合，以优化毛细管电泳分析的天然荧光神经递质的紫外荧光检测。这项研究将推动亚细胞水平上神经元化学定量测量的努力。提高各种天然荧光神经递质的可检测性将为表征细胞间化学信号传导的基本机制提供新的能力。

This starter grant award of the Chemistry Division to the University of Texas at Austin supports the research of Professor Jason B. Shear. The theme of the research is ultraviolet fluorescence detection of biological chromophores. The work investigates the mechanisms and extent of multiphoton-excited degradation of monoamine neurotransmitters excited using different numbers of photons of different characteristic wavelengths. Comparisons are made of the photodestruction quantum yields for three-photon excitation of neurotransmitters using a modelocked titanium:sapphire laser in the near-infrared wavelength range, and for two-photon excitation using a frequency doubled titanium:sapphire laser. Sources of background in both two- and three-photon excited fluorescence measurements are evaluated and used in combination with the photodestruction measurements to optimize ultraviolet fluorescence detection of natively fluorescent neurotransmitters analyzed with capillary electrophoresis. The research will advance efforts toward quantitative measurement of neuronal chemistry at the subcellular level. Improved detectability of a variety of natively fluorescent neurotransmitters will provide new capabilities for characterizing fundamental mechanisms of chemical signalling between cells.