基于时间相关单光子计数的荧光寿命成像技术

采用时域法中的时间相关单光子计数方法记录荧光寿命,时间相关单光子计数采用多波长通道同时记录荧光光子数,可以提高计数效率和信息量,还可以在稳态图像中分离不同荧光团,形成4维图像。并采用多光子激发技术,利用长波长光源发出的两个或多个光子可以激发出一个短波长的光子。多个光子必须几乎同时到达激发点,才能提供被激发分子足够的能量以产生荧光。多光子激发波长较长,生物组织对其散射减小,因而可以穿透到更深层的组织,从而提高荧光成像深度和空间分辨力,并减少对活体样品的损伤。

Fluorescence lifetime imaging based on time-correlated single photon counting

The key technology of fluorescence lifetime imaging microscopy is introduced. Time-correlated single photon counting in time-domain method is adopted to record fluorescence lifetime. The counting efficiency and the amount of information in the data can be increased by recording the fluorescence in several wavelength channels simultaneously. Multi-wavelength imaging is used to separate different chromophores in stead-state images. Thus the image is build up with four dimension. On the other hand, multi-photon exciting technology is used in the system. Two or more photons emitted by long-wave light source can excite a short-wave one. Several photons must reach the excited point simultaneously to produce enough energy to excite fluorescence. The long wavelength emitting light in multi-photon