We describe the first fluorescence lifetime images of cells. To demonstrate this new capability we measured intracellular images of Ca2+ in COS cells based on the Ca(2+)-dependent fluorescence lifetime of Quin-2. Apparent fluorescence lifetimes were measured by the phase-modulation method using a gain-modulated image intensifier and a slow-scan CCD camera. We describe methods to correct the images for photobleaching during acquisition of the data, and to correct for the position-dependent response of the image intensifier. The phase angle Quin-2 images were found to yield lower than expected Ca2+ concentrations, which appears to be the result of the formation of fluorescent photoproducts by Quin-2. Fluorescence lifetime imaging (FLIM) does not require wavelength-radiometric probes and appears to provide new opportunities for chemical imaging of cells.

中文翻译：

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使用Quin-2对COS细胞中细胞内钙的荧光寿命成像。

我们描述了细胞的第一个荧光寿命图像。为了证明这一新功能，我们基于Quin-2的Ca（2+）依赖性荧光寿命，测量了COS细胞中Ca2 +的细胞内图像。通过使用增益调制图像增强器和慢速扫描CCD相机的相位调制方法测量表观荧光寿命。我们描述了在数据采集过程中校正图像以进行光漂白的方法，以及校正图像增强器的位置相关响应的方法。发现相角Quin-2图像产生的Ca2 +浓度低于预期，这似乎是Quin-2形成荧光光产物的结果。