Martyński Michal, Zydlewicz Jolanta, Boens Noël, Molski Andrzej
Laboratory for Dynamics of Physicochemical Processes, Adam Mickiewicz University, Grunwaldzka 6, 60-780 Poznań, Poland.
J Chem Phys. 2005 Apr 1;122(13):134507. doi: 10.1063/1.1875012.
Triplet blinking is a phenomenon observed commonly in single molecule fluorescence spectroscopy. At high to moderate excitation intensities one can distinguish bright (on) and dark (off) periods in the fluorescence intensity trajectory caused by sojourns into the nonemissive triplet state. In this work, we focus on triplet blinking of an immobilized molecule in the low excitation regime, where a threshold between on and off intensity levels cannot be set, and, therefore, a standard on/off analysis of fluorescence intensity trajectories is not possible. In the low excitation regime triplet blinking parameters can be recovered from photon arrival time trajectories, i.e., records of individual photon arrival time. We use computer-generated data to compare the recovery of the triplet blinking parameters from the intensity correlation function (ICF) and the histogram of interarrival time. We have found that the ICF offers a better statistics for the recovery of the triplet blinking parameters.
三重态闪烁是单分子荧光光谱中常见的一种现象。在高至中等激发强度下，由于分子进入非发射三重态的驻留时间，荧光强度轨迹中会出现亮（开）和暗（关）周期，这是可以区分的。在这项工作中，我们关注低激发态下固定分子的三重态闪烁，在此状态下无法设定开和关强度水平之间的阈值，因此，对荧光强度轨迹进行标准的开/关分析是不可能的。在低激发态下，三重态闪烁参数可以从光子到达时间轨迹中恢复，即单个光子到达时间的记录。我们使用计算机生成的数据来比较从强度相关函数（ICF）和到达时间间隔直方图中恢复三重态闪烁参数的情况。我们发现，ICF为三重态闪烁参数的恢复提供了更好的统计数据。
