4-[(4-(((1,1-DIMETHYLETHYL)OXIDOIMINO)METHYL)PHENOXY)BUTYL]TRIPHENYLPHOSPHONIUM BROMIDE

MitoPBN is a mitochondria-targeted antioxidant.¹ It accumulates in the mitochondria following the generation of a mitochondrial membrane potential by succinate, an effect that is blocked by addition of the mitochondrial membrane potential uncoupler FCCP . MitoPBN inhibits superoxide activation of mitochondrial uncoupling protein 1 (UCP1), UCP2, and UCP3 when used at a concentration of 250 nM in vitro but does not react with superoxide. It traps hydroxyl (IC₅₀ = ~77 μM) and carbon-centered radicals and inhibits the initiation of lipid peroxidation in isolated bovine heart mitochondria.

1. Murphy, M.P., Echtay, K.S., Blaikie, F.H., et al. Superoxide activates uncoupling proteins by generating carbon-centered radicals and initiating lipid peroxidation: Studies using a mitochondria-targeted spin trap derived from α-phenyl-N-tert-butylnitrone J. Biol. Chem. 278(49),48534-48545(2003).