Development of a Femtosecond Circular Dichroism Spectrometer for Research and Education

在主要研究仪器（MRI）计划的支持下，波士顿学院化学系的Torsten Fiebig将开发用于研究和教育的飞秒圆二色光谱仪。 目前，商用圆二色光谱仪仅可用于稳态操作。然而，实时监测圆二色光谱的变化提供了分子系统的结构和动力学信息。到目前为止，用于时间分辨CD测量的实验室阶段的实验装置被设计成在毫秒到皮秒的时间范围内监测动态。早期测量超快时间分辨CD光谱（在皮秒时间尺度上）的尝试利用可调谐激光脉冲与单波长检测方案相结合。因此，不是同时测量整个CD光谱，而是必须逐点重建，这显著加剧了数据采集和数据分析过程。Fiebig教授将设计和建造一个宽带飞秒时间分辨圆二色光谱仪，能够同时采集大光谱区域（紫外到近红外）的数据。 该仪器将成为研究蛋白质折叠和分子识别的有力工具。

With support from the Major Research Instrumentation (MRI) Program, Torsten Fiebig in the Department of Chemistry at Boston College will develop a femtosecond circular dichroism spectrometer for research and education. Currently, commercial circular dichroism spectrometers are only available for steady state operations. However, monitoring the real-time change of a circular dichroism spectrum provides both structural and dynamical information about molecular systems. Up to now laboratory-stage experimental setups for time resolved CD measurements were designed to monitor dynamics in the time range of millisecond to picoseconds. Earlier attempts to measure ultrafast time-resolved CD spectra (on the picosecond time scale) utilized tunable laser pulses combined with single-wavelength detection schemes. Thus instead of measuring the entire CD spectrum simultaneously it had to be reconstructed point by point which exacerbates the data acquisition and data analysis procedure significantly. Prof. Fiebig will design and construct a broadband femtosecond time-resolved circular dichroism spectrometer with the capability of simultaneously acquiring data over a large spectral region (ultraviolet to near infrared). This instrument will be a very powerful tool in studies of protein folding and molecular recognition.