Experiment note

I am measuring interactions between two proteins tagged with fluorescence proteins using fluorescence lifetime microscope. One important thing for my experiments is controling protein-expression level of the two target proteins. For almost a year, I have looked for the condition that gives me the highest signal-to-noise ratio, and in the same time minimum effects to cells. In my experiences, the most difficult things in biophysical measurements are usually not in building equipments. Finding right condition always take much more time.
Sigh. The laser condition is not great these days. I got nice bright transfected neurons today, but laser stopped working before I begun my experiments.