Staining mix A

Recipe

Reagent	Amount to add (for 20 mL)	Final concentration
Dulbecco’s PBS for lipid labeling	18.875 mL
3-Azido-7-(diethylamino) coumarin (40 mM prepared in DMSO)^a	25 μL	50 μM
CuSO₄ (100 mM prepared in H₂O)	200 μL	1 mM
Tris-(benzyltriazolyl-methyl)amine (200 mM prepared in DMSO)	100 μL	1 mM
Sodium ascorbate (2.5 M prepared in H₂O)	800 μL	100 mM

Prepare the mix fresh immediately before each labeling experiment.
^aSee Sivakumar et al. 2004 (Sivakumar K, Xie F, Cash BM, Long S, Barnhill HN, Wang Q. 2004. A fluorogenic 1,3-dipolar cycloaddition reaction of 3-azidocoumarins and acetylenes. Org Lett 6: 4603-4606).