【摘要】 生物大分子动态的结构变化能够使用单分子对荧光共振能量转移谱技术来研究。主要研究了微腔在单分子对共振能量转移实验中有效提高相应单分子对的荧光发射信号的作用,从而提高该技术的时间分辨率。研究发现,由于受体-微腔的强耦合相互作用,光学微腔使得受体分子变成了一个类似于单原子激光的激光体。此外,随着距离的增加,受体的光子数会很快下降。微腔使受体的发射光对单分子对间的距离有更大的依赖性,在腔体中进行单分子对共振能量转移实验可以得到更高的时间分辨率。研究结果为单分子对荧光共振能量转移技术提供了实验方法和理论指导。更多还原

【Abstract】 Dynamic structural changes of bio-macromolecules undergoing biochemical reactions can be studied using the single-pair fluorescence resonance energy transfer (sp-FRET) experiments, which can be used as a nanoscale ruler. The ability to use the optical microcavity to amplify the sp-FRET fluorescence signal has been investigated. When the single FRET-coupled pair and the attached bio-macromolecule are placed in an optical cavity with the emission mode of the acceptor dye in resonance with the cavity mode, the results of a fully quantum-mechanical treatment show that, the photon emission intensity from acceptor amplified by the cavity coupling field mode would reach a significant value, leading to a much brighter photon signal. It is concluded that the microcavity can serve as a sharper structural-sensitivity observable tool to the distance of single pair. The work establishes experimental methods and useful guidelines for the single-molecule studies of biomacromolecules in real time at molecule scale.更多还原