Red-orange fluorescent cytoskeleton stain. Binds and labels F-actin. For most fluorescent imaging applications, cells should to be fixed and permeablilized. Excitation/emission maxima λ ~ 540/565 nm We suggest making up a stock solution of this product by dissolving the vial contents in 1.5 mL methanol or DMSO. Please refer to the protocol tab for further information on using this product.. Purity 90%. MW (observed): 1231.4