(Arg)9
(Arg)9 (Nona-L-arginine) is a cell-penetrating peptide (CPP) made up of 9 arginine residues, which is an inhibitor of serine endoprotease Furin. (Arg)9 has neuroprotective property, exhibits neuroprotective activity with an IC50 of 0.78 μM in the glutamic acid model.