Also available in 5 mg, 10 mg, 25 mg, 50 mg, 100 mg and bulk. Please contact Fisher for quotes. Coelenteramine 400a (Coelenterazine 400a), a Coelenterazine derivative, serves as a substrate for Renilla luciferase (RLuc), facilitating the emission of blue light at 395 nm [1] [2]. This compound alters the bioluminescence color of RLuc by substituting the sulfur and oxygen heteroatoms in the methylene bridge. Coelenteramine 400a enhances signal resolution, proving useful in bioluminescence resonance energy transfer (BRET) research [3]. Purity 98.15%