Coelenterazine 400a, also called DeepBlueC™, is a coelenterazine derivative that serves as a substrate for Renilla luciferase (Rluc) and generates an emission peak centered around 400 nm. It is the preferred Rluc substrate for BRET studies because it has minimal interference with the emission of the GFP acceptor. Yellow solid soluble in MeOH or EtOH Store at 20°C and protect from light C26H21N3O MW: 391.46DeepBlueC is a trademark of BioSignal Packard.