用双光子激发荧光进行单分子探测的实验研究  

THE EXPERIMENTAL STUDY OF SINGLE-MOLECULE DETECTION BY TWO-PHOTON-EXCITED FLUORESCENCE

作　　者：马万云[1] 张亮[1] 刘岗[1] 朱峰[1] 陈光[1] 文克玲[1] 陈瓞延[1] 

机构地区：[1]清华大学现代应用物理系单原子分子测控实验室

出　　处：《原子与分子物理学报》1998年第S1期193-195,共3页Journal of Atomic and Molecular Physics

基　　金：国家自然科学基金

摘　　要：介绍自行研制的基于飞秒激光双光子激发荧光的单分子探测谱仪，以及对水溶液中香豆素４４５（Ｃ４４５）分子的初步实验结果。オhis paper describes the method of single-molecule detection in a flowing solution by two-photon-excited fluorescence. The titanium-sapphire self mode-locked laser produces a pulse with about 70 fs temporal width and 82MHz repetition rate at 730nm. Its highest average power was about 1W. The laser beam was focused into a thin wall capillary flow cell. The probe volume was about 3pL. Fluorescence was collected at 90° and was detected by a fast response PMT detector. The preliminary result about the detection limit for C445 was about 2×10^-12 mol/L using the criterion of 3 standard deviations above background. the average probability for a C445 molecule being present in the detectors probed volume was about 4 at the detection limit. 

关 键 词：单分子探测 双光子激发荧光 C445 

分 类 号：O561.2[理学—原子与分子物理]