I have to do a FACS experiment with my HEK293 cells, but we have to do this experiment in an other building. Can I transport them 30 minutes in RT PBS (on ice better?) and doing a FACS experiment for 2 hours, before I perform a cell lysis?
Since, for the FACS, you need your cells in suspension. Why don't you process all your samples before going to the facility?
You can trypsinize and wash your HEK293 cells and then perform your preparation (e.g.: fixation and staining depending on what you want to do). If you store your samples tubes on ice during the travel, I don't think that you'll have trouble when you'll read them at the FACS.