With a slow-scan CCD camera, integrating for a long time, we could just observe the signal from leciferase/luciferin. Given the short dwell time per pixel of the confocal, I would be surprised if it would be a sufficiently efficient light collecting device to image the weak signal. ScottFraser >Has anyone tried collecting light emission from luciferin using a confocal >microscope? We are using luciferase as a reporter gene, inserted into >neurons. The peak emission is at 560 nm, within the range for rhodamine >detection. We do not actually require an excitation beam, not if the gene >is turned on. > >Judy Trogadis >Eye Research Institute of Canada and >University of Toronto Scott Fraser ([log in to unmask]) Caltech, Beckman Institute (139-74) Pasadena, CA 91125 818 395-2790 telephone 818 449-5163 fax