Ultra Fast Fluorescence Microscopy

In this project a conventional wide-field fluorescence microscope is used in combination with pulsed laser excitation. The detection system consists of a gated image intensifier and a fast CCD camera(1000 frames/second). The combination of the pulsed light source and the image intensifier, which can be gated with sub-nanosecond rise times, is here employed for fluorescence lifetime imaging. The fluorescence lifetimes of the dyes are sensitive to their local environment and can be used to monitor various microscopic properties of the sample. Fluorescence lifetime imaging can for instance be emplyed to quantitatively image calcium ions, oxygen concentration, pH etc.


Initially we will use the system to study the signal transduction between hart cells. Here, the transfer of information is achieved through action potentials. Cell membranes which are electronically excited become permeable for Calcium ions, which will be visualized under the microscope. We will study the signal transduction between hart cells which were grown under different physiological conditions (e.g. high/low blood pressure) and hope to come to a better understanding of the influence of physiological conditions on the hart cell function.