基于双光子激发的荧光相关谱测量

Fluorescence Correlation Spectroscopy Based upon Two-Photon Excitation

本文利用多光子激发激光扫描显微镜的部分光路和探测器,建立了双光子荧光相关谱系统(Two-PhotonFluorescenceCorrelationSpectroscopy,简称TP-FCS)。利用TP-FCS系统观察到了"光子爆发"现象,实现了染料分子的双光子激发,测量出若丹明B染料分子在蔗糖溶液中的扩散系数。实验证明该系统具有操作简便、可靠性高、费用低廉等特点,可实现单分子检测。

A Two-Photon Fluorescence Correlation Spectroscopy (TP-FCS) system was set up dependent on a part of optical block and detector of the multi-photon laser scanning microscope. The phenomenon 'photon-burst' was observed and single rhodamine B molecule was excitated from the TP-FCS system. Meanwhile, the diffusion coefficient of rhodamine B molecule in sucrose aqueous solution was calculated. It was proved that this system had the advantages of handy operation, low cost and high reliability and could be used to detect single molecule.