摘要
研究了激发光增强时其对荧光关联谱 (FCS)测量的影响 .强激发光产生的饱和激发会改变激光诱导荧光的空间分布函数 ,从而影响FCS的测量结果 .首先根据饱和吸收的物理模型 ,推导出强激发光情况下有效探测区域变化的定量公式 ,获得了FCS测量所得到的粒子数和扩散时间与饱和激发光强和激光光强的函数关系 ,并用于消除饱和吸收造成的系统误差 .采用Monte Carlo模拟方法和实验 ,对理论分析结果进行了验证 .这将有助于完善FCS分析方法的理论模型 。
In this paper,we study the errors caused by an intense excitation beam in fluorescence correlation spectroscopy (FCS). Saturated excitation induced by an intense excitation beam will alter the spatial distribution function of the laser_induced fluorescence; therefore it changes the results of FCS measurements. Using the theory for saturated excitation,we derived a general expression for the effective detection volume as a function of the excitation laser intensity. Quantitative relations between the particle number and diffusion time,both obtained from FCS measurements,and the excitation laser intensity are established and used to remove the systematic error due to saturated excitation. The success of this technique is demonstrated in both Monte Carlo simulations and experiments.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2004年第8期2503-2508,共6页
Acta Physica Sinica
基金
国家自然科学基金 (批准号 :1992 840 8
60 13 80 10
10 2 740 3 9)资助的课题~~
