Greetings,

I have been using the viviren luminescence substrate for bioassay development. I transfect cells with plasmid expressing Renilla luciferase. In vitro, viviren is converted to coelenterazine by intracellular esterases and this is then oxidized by luciferase to form coelenteramide, which produces CO2 and luminescence.

Lately, I have had trouble producing signal - I believe it is due to old reagent. Overtime after viviren is dissolved in DMSO, the solution turns from yellow to brown, likely due to spontaneous oxidation. Has anyone had any experience with this reagent and can give me some advice?

Any help is greatly appreciated, thank you!

Kevin