C₁₈H₁₇N₉O₁₀PS•Na; MW 605.4; λ_max 463 nm; ε 22000 (MeOH); sodium salt, purity > 95% HPLC. For other salt forms or metabolites please inquire. Potent membrane-permeant fluorescent activator of both isozymes I α and I β of cGMP-dependent protein kinase. While 8-NBD-cGMP is almost nonfluorescent in aqueous solutions, it fluoresces strongly in hydrophobic environments such as hydrophobic protein binding sites; λ_exc 475 nm, λ_em 525 nm. Detailed technical information available. Reference: Ruf et al. in Heilmeyer (ed.), Signal Transduction and Protein Phosphorylation, Ser. A, Life Sci., 135, 99 - 104 ( 1987), Plenum Press, NATO ASI.