I use Fluo-3 AM to monitor calcium fluxes in endothelial cells exposed to flow in a flow chamber mounted on a krypton/argon confocal (Leica). I need to extend the experiment time out to an hour. The fluo-3 is retained, but it will be necessary to calibrate the signal in different experiments. I am planning to use a dual dye loading technique and intend to try CMTMR co-loaded with the Fluo-3. I know that there is an assumption of similar dye distributions. Has anyone tried this technique for this purpose? Any comments on CMTMR or possible alternative dyes that could be suitable? ----------------------------------------------------------------------- Dr. Natalie James CSIRO Division of Biomolecular Engineering Riverside Corporate Park PO Box 184 North Ryde NSW 2113, AUSTRALIA [log in to unmask] (Ph) 61-2-886-4885 (Fax) 61-2-886-4818